flip nepal final report

Soil Investigation of Proposed BUILDING Foundations At SARANKOT, Kaski, Nepal

I

Material Test Pvt. Ltd. Mid Baneshwor, Kathmandu

Table of Contents 1. GEOLOGICAL INVESTIGATION ....................................................................................................................... 1

1.1. Introduction ................................................................................................................................................................................ 1

1.2. Location and Description of Area ................................................................................................................................... 1

1.3. Objectives .................................................................................................................................................................................... 1

1.4. Regional Geology of the Project Area .......................................................................................................................... 2

1.5. Surface Geology ....................................................................................................................................................................... 4

1.6. Slope Stability ............................................................................................................................................................................ 4

1.7. Recommended Drilling ......................................................................................................................................................... 6

1.8. Recommendation ..................................................................................................................................................................... 6

2. GEO-TECHNICAL INVESTIGATION................................................................................................................. 9

2.1 Soil Investigation of the Proposed Area ...................................................................................................................... 9

2.2 Planning of works .................................................................................................................................................................... 9

2.3 Geo-technical Exploration ................................................................................................................................................... 9

2.3.1 Boring............................................................................................................................................................................. 10

2.3.2 Sampling ....................................................................................................................................................................... 11

2.3.3 Field Test ....................................................................................................................................................................... 11

2.4 Generalize Borehole-Log (Subsurface) findings ..................................................................................................... 15

2.5 Analysis of Allowable Bearing Pressure ...................................................................................................................... 16

2.5.1 Correlation between SPT and DCPT ............................................................................................................... 16

2.5.2 SPT correction ............................................................................................................................................................ 16

2.5.3 Allowable Bearing Pressure based on Ultimate Bearing Capacity................................................... 18

2.5.4 Allowable Bearing Pressure based on Tolerable Settlement .............................................................. 19

2.5.5 Pile Foundation ......................................................................................................................................................... 20

2.5.6 Estimation of Bearing Capacity (Rock/Boulder) ........................................................................................ 21

2.5.7 Analysis of Foundations ........................................................................................................................................ 24

2.6 Conclusion and Recommendation ................................................................................................................................ 34

2.7 References and Standards ................................................................................................................................................. 37


FLIP NEPAL/KASKI/ September - 2014 Page 1


1. GEOLOGICAL INVESTIGATION

1.1. Introduction

M/S FLIP NEPAL RESORTS PTE LTD is proposed to construct the Hotel Building in between

Naudanda and Sarankot of Kaski District, Nepal. Material Test (P) Ltd. was entrusted to carry out

the Detail Geo-Technical Investigation of proposed building site at under contract made by FLIP

NEPAL.

A team headed by Senior Geologist (Dr. P. D. Ullak), including Senior Engineer (Madhukar

Karki), Geo-technical Engineer (Kishor Paudel) and contractors representative Er. Raj Thapa

visited site on July 26, of 2014.

The report is about visual observation and general geological condition of the sites, detail drilling

and laboratory tests.

1.2. Location and Description of Area

The proposed project site is located in north-west of Pokhara, Kaski District, Gandaki Zone. The

area can be accessed by black topped road about 20 km north from Pokhara along Pokhara-

Baglung Road. The proposed area is about 3 km away from Naudanda village along Sarangkot

road.

1.3. Objectives

The following scopes of works were covered under this study:

Preliminary observation of soil condition

Slope stability analysis of the proposed construction area

Exploration of the sub-surface conditions at various locations of proposed foundation sites

and conduct requisite in-situ tests.

Limited laboratory testing of representative samples obtained during the field investigation

to evaluate relevant engineering parameters of the subsurface soils.

Engineering analyses.

The scope of this investigation report includes:

Geological Assessment

Drill logs

Assessment of bearing capacity

Recommendations of foundation type and depth




1.4. Regional Geology of the Project Area

The project area lies in the Lesser Himalayan rocks; structurally this zone is located in 20 km south

of the Main Central Thrust (MCT) zone. The lithostratigraphy of the Lesser Himalaya is presented

in Figure 1 and Table 1. Geologically, the proposed construction area (Sarangkot) is covered with

phyllite and quartzite. The effect of the MCT is considered as minimum, although the area has

active MCT zone. The active MCT zone passes through Taprang village along the Madi River.

Table 1: Lithostratigraphy of Western Nepal Himalaya (DMG, 1987)

Group Formation Lithology Age

SIWALIKS

MAIN BOUNDARY THRUST (MBT)

Midland

Lakharpata Limestone, limestone, shale

Upper Pre-

Cambrian -Late Paleozoic

Syangja Quartzite, limestone, shale

Sangram Shale, limestone and quartzite

Galyang Slate, limestone

Ghanpokhara Slate, limestone, quartzite

Seti* Gritty phyllite, phyllite, quartzite

Ulleri Augen gneiss

MAIN CENTRAL THRUST (MCT)

HIGHER HIMALAYA

Table 2: Lithostratigraphy of Central-Eastern Nepal Himalaya (DMG, 1987)

Lithological

Units

Thickness (m) Lithological characters Age

Siwalik Group 6,000 Mudstone, sandstone and

conglomerate

Neogene

--------------------Main Boundary Thrust (MBT)--------------------

Suri Dobhan Augen gneiss*

>200 Augen gneisses, schist and quartzite

Pre-

Cambrian-

Lower Paleozoic

Laduk Phyllite* 1,000-2,000 Phyllite, chlorite-schist and

sandy-phyllite

Chagu-Chilangka

Gneiss

400-700 Tourmaline bearing augen

gneiss

Khare Phyllite 2,500 Schist, quartzite, slates and

limestone

--------------------Main Central Thrust (MCT)-----------------

Lesser Himalaya

The Lesser Himalaya consists of low-grade metamorphic rocks like quartzite, slate and phyllite.

Based on the lithological characters the rocks of the Lesser Himalaya is subdivided into the

Lakharpata, Syangja, Sangram, Galyang, Ghanpokhara, Seti, Ulleri formations in ascending order.

Lakharpata Formation

The Lakharpata Formation is composed of thick bedded, fine-grained, grey to bluish grey dolomite

and limestone. Estimated thickness of this bed is around 3000m.




Syangja Formation

This lithounit often begins with a coarse quartzite bed several tens of meters thick. It is mainly

composed of quartzite, slate. The total thickness is 1,000 m.

Sangram Formation

The unit is represented by thick bedded limestone and quartzite. Thickness of the unit is more than

1,000 m.

Figure 1: Regional Geological Map

Galyang Formation

This lithounit characterized by presence of calcareous slate and limestone as well as slate, slate.

The total thickness is 1,000 m.

Ghanpokhara Formation

This lithounit characterized by presence of slate and limestone as well as quartzite. The total

thickness is 800 m.

Seti Formation

The Seti Formation is represented by presence of grey to milky white quartzite intercalated with

phyllite and schist. The total thickness is 3,000 m.

Project Area




Ulleri Formation

This lithounit characterized by presence of augen gneiss and schist only and attain thickness about

800 m.

The existing geology of proposed hotel building area belongs to the rocks of the Seti formation,

Lesser Himalaya. The area is covered by phyllite, slate and quartzite (Seti formation). However,

underneath part of the rock is topped by residual soil with alluvial and colluvial deposits.

1.5. Surface Geology

The existing site area is mostly covered by residual soil and colluvial deposits. Thickness of

residual soil ranges from 1 m to 3 m, whereas colluvial deposits ranges from 1 m to 4 m depths.

Bedrocks are observed along newly constructed road alignment nearby proposed hotel entrance.

Rocks are visible at around 10% surface of proposed hotel areas. Exposed rocks are of fresh to

slightly weathered, phyllite and quartzite.

Along the road section from Naudanda to Sarangkot, bedrocks of phyllite and quartzite are exposed

on the hill slope. Proportion of the phyllite is greater than quartzite. On the surface, the rocks are

slightly weathered. Thickness of the phyllite is around 10 cm to 15 cm.

1.6. Slope Stability

The slope stability condition is fair to good (Table 2 and Figure 2). Generally the natural hill slope

is oriented southwest direction with low angle dipping (10-20). The foliation plane is oriented

northeast. So, the stability condition is good due to opposite slope of the hill slope and foliation

plane. The dip of the hill slope is very low (10-20), low height cut slope, covered by forest, with

stepping topography on hill slope. The joints also oriented in opposite to the hill slope and long

spacing can be seen in the exposed rocks.

Slope nearby Entrance Area




Slope nearby Hotel Block B

Slope nearby Sherpa Block

Slope nearby Naudanda-Sarangkot road

The slope of the hill on the back side (North-east) of the project area has steep in nature, the

dipping of the hill slope and foliation plane is nearly oriented at same direction, so there is little




possibility of the plane failure, whereas sufficient setback (more than 10 m) from north end

prevents proposed area from probable damage by slope failure.

The staff dormitory area is geologically safe as slope is gentle and required cutting height is not

much.

Table 2: Slope stability condition

Location HS/F F/J1 F/J2 F/J3 J1/J2 J2/J3 J3/J1

Starting point of entrance Stable Stable Unstable Stable Stable Stable Stable

Just below the Hotel Block B Stable Stable Stable Stable

Just below the Sherpa Block Stable Stable Unstable Stable Stable Stable Stable

Along the road section

Naudanda and Sarangkot

Stable Stable Stable Stable Stable Stable Stable

1.7. Recommended Drilling

Altogether 9 nos. of borehole are plausible for the drilling to identify the subsurface condition of

the area. (Refer Table 3). One borehole location, D1 is shifted by 4 m west from the previously

proposed location of Block B, as rock bed is undulating and exposure has been noticed about 50 m

west only.

D2 is newly proposed, whereas D5 and D6, at Sherpa Block is recommended as rock exposure is

rear nearby this block and topographically it is slightly elevated. Other drilling points are same as

proposed by the client.

Table 3: Depth of proposed drilling holes

Drill hole Location Proposed Depth

D1 Hotel Block B (Shift 4 m to west) 10 ~ 15 m

D2 Hotel Block B (Add new hole) 10 ~ 15 m

D3 Hotel Block A 10 ~ 15 m

D4 Hotel Block A 10 ~ 15 m

D5 Sherpa Block (add new hole) 8 ~ 10 m

D6 Sherpa Block (add new hole) 8 ~ 10 m

D7 Just below the Hotel Block B 8 ~ 10 m

D8 Staff Dormitory 10 ~ 15 m

D9 Staff Dormitory 10 ~ 15 m

Total 84 ~ 120 m

Drilling should stop, either after drilling up to a proposed depth or 5 ~6 m after encounter of

rock deposit

1.8. Recommendation

The project area is located in rocks of Seti formation, Lesser Himalaya. The Seti

Formation is composed of thick bedded phyllite and quartzite.




8~9 holes are sufficient to verify the stability and to asses the bearing capacity of soil

strata.

The slope stability condition is good on hill slope so there is no possibility to occur the

slide and any other major/minor failures. However, it is recommended to construct the

wall on the hill slope along the cutting slope of road and building with sufficient weep

holes with well managed drains.

On the basis of site geology, existing topography, folliation planes, bedding of rocks,

slope os hills, the proposed building (Hotel) construction area is observed as stable and

sound.

It is highly recommended to design building foundation, so that base of footing can rest of

bed rocks.

Figure 2: Proposed Location of Drill hole




PHOTOGRAPHS OF SOIL/ROCK EXPOSURE

Plate 1: Bedrock Phyllite

exposed at entrance area

Plate 2: Drilling location at

Dormitory area, gentle hill

slope

Plate 3: Way to Hotel area

Plate 4: Gentle slope with

residual soil

Plate 5: Bedrocks just below

the Hotel Block B

Plate 6: Gentle slope area

Plate 7: Hotel Block B and A

area on ridge area

Plate 8: Hotel Block A area

on ridge area

Plate 9: Just below the

Sherpa block area requires

the wall

Plate 10: Back side of the

area

Plate 11: Sherpa Block area

elevated area

Plate 12: Top area of the

proposed hotel area




2. GEO-TECHNICAL INVESTIGATION

2.1 Soil Investigation of the Proposed Area

This section presents the result of soil investigation for the design of a Foundation of FLIP NEPAL

RESORT building at Sarankot, Kaski, Nepal. The investigation characterizes the subsurface

conditions and develops the necessary requirement for the proposed safe bearing capacity of the

foundation.

The soil investigation work was carried out on August-September of 2014. The total quantity of

soil investigation included eight boreholes, each of ranging from 10 m 15 m depth as per

understanding and requirement. Standard Penetration Tests (SPT) and Dynamic Cone Penetration

Tests (DCPT) were conducted at 1.0 to 1.5m depth intervals or as per convenience to furnish the

compactness of the soil strata at field.

2.2 Planning of works

Work schedule, location of these boreholes and other project specific issues were identified on

mutual understanding between drilling consultant and client engineer during a desk study, which

was carried out immediately after finalization of agreement in-between. Immediately after initial

site visit by experts, drilling team had revised methodology depending upon the changes on

environment, geological and local conditions.

Table 4 Proposed Laboratory investigation of Soil

SPT samples

(as per change in strata)

U/D samples

(at least 1 in each hole if

cohesive strata)

Rock / Boulder

(at least 1 in each hole)

Natural Moisture test Specific Gravity test

Liquid limit / Plastic Limit test

Grain Size Distribution test Unit weight

Direct shear test

Natural Moisture test Specific Gravity test

Liquid limit / Plastic Limit test

Grain Size Distribution test Unit weight/ Bulk density

Uni-confined compression test

Consolidation test

Unit weight Point load Test

Uni-axial Compression Test

2.3 Geo-technical Exploration

Geological condition/stratum at the test site is important aspect to determine the depth, size and

types of foundation. Drilling can define the characteristic and strength of soil and rock in both

unstable and stable zones. Dynamic Cone Penetration Tests were carried out in different depths can

give appropriateness of the densification of the soil strata. Ground water table, cavities and changes

in strata are major aspect of drilling.

As drilling location lies on alluvial deposit followed by rocky strata within proposed drilling depth,

drilling team have been mobilized with rotary drilling rig. Safety mechanisms were developed for




technical team and workers.

2.3.1 Boring

Boring works were carried out using Rotary Drilling Rig. Whole investigation works were

conducted as per IS 1892: 1979 Code of practice for subsurface investigations for foundations

(First revision) 1979 Soil and foundation engineering

Figure 3: SPT test @ proposed hole D9

Figure 4: Soil Sample abstracted on Split Spooner at hole D9




Groundwater was monitored on drilled holes 24 hours after completion of drilling works.

2.3.2 Sampling

The samples were obtained as per IS 8763: 1978 Guide for undisturbed sampling of sands and

sandy soils 1978 Soil and foundation engineering

Figure 5: Preparation for Sounding Test (SPT) at borehole D8

2.3.3 Field Test

Figure 6: Highly weathered phyllitic rock sample on split spooner after SPT test




SPT Test/DCPT

The number of blows required to drive the split-spoon/cone was recorded at every 150 mm of

penetration till the total penetration was 450 mm. The number of blows recorded for the last two

successive 150 mm penetration are added and expressed as SPT/DCPT N-value.

Figure 7: Preparation for SPT test on D7

Figure 8: Drilling in progress with SPT arrangement at D1





DCPT

In-situ penetration tests have been widely used in geotechnical and foundation engineering for site

investigation in support of analysis and design. The dynamic cone penetration test (DCPT) is

typical in-situ penetration tests. The dynamic cone penetration test shows features of both the CPT

and the SPT. The Dynamic Cone Penetration (DCPT) is similar to the SPT in test.






It is performed by dropping a hammer from a certain fall height and measuring a penetration depth

per blow for each tested depth. Therefore, it is quite similar to the procedure of obtaining the blow

count N using the soil sampler in the SPT. In the DCPT, however, a cone is used to obtain the

penetration depth instead of using the split spoon soil sampler. In this respect, there is some

resemblance with the DCPT in the fact that both tests create a cavity during penetration and

generate a cavity expansion resistance.

The shape of the dynamic cone is similar to that of the penetrometer used in the CPT. Cone having

standard apex angle of 60 at its lower end was driven into the ground at the base of the borehole

by means of a 63.5 kg hammer falling from a height of 760 mm. (DCPT) were carried out in the

borehole at 1.5m depth intervals.

DCPT tests were conducted on hard strata and sometime soft strata containing gravelly to boulder

mix soil at similar interval like SPT. Only disturbed samples were abstracted from strata where

DCPT conducted.

There has not been direct correlation between DCPT and shear strength. The correlation

between SPT and DCPT is yet to be proven. DCPT values start increasing and deviating from

the SPT values (due to skin friction). It is difficult to figure out what are the condition that

the DCPT and SPT are comparable and when are not. However, until we have SPT values of

adjacent layer, DCPT blow count were used as a qualitative tool, not quantitative.

The nature of the subsoil was investigated from the debris collected at different depths to identify




the stratification and type of soil at initial stage. Disturbed soil samples were retrieved from boring

tools at depth intervals of 1.5m. The samples were wrapped in plastic bags and labeled.

The recorded DCPT values are without any correction of overburden pressure and water table. The

test was conducted without using liner. The maximum rod length used was 15 m.

2.4 Generalize Borehole-Log (Subsurface) findings

Project

Name

Borehole

Identity

Generalize

depth, m

Generalize soil Characteristic

FLIP

NEPAL

RESORT

BUILDING

D - 1

0.0 2.20 Brownish grey dense sandy silt with small gravel of weathered

phyllite

2.20 15.00 Radish brown to yellowish white highly weathered phyllitic

rock (WEAK BED ROCK)

D - 2

0.0 3.65 Light grey to brownish medium dense to dense sandy gravel

with fresh to weathered fragments of phyllite with quartzite

3.65 15.00 Brownish fresh to slightly weathered phyllitic rock with

quartzite (WEAK BED ROCK)

D - 3

0.0 1.65 Light grey to brownish medium dense sandy silt with small

gravel and clayey traces

1.65 4.20 Radish brown medium dense to dense sandy soil with gravel

and fragments of weathered phyllite

4.20 -15.00 Light grey to brownish slightly weathered and highly fractured

fine grained quartzite with phyllite (WEAK BED ROCK)

D - 4

0.0 1.15 Dark grey to reddish soft sandy soil with clayey traces

1.15 -5.10 Radish brown medium dense to dense highly fractured

fragments of phyllite and quartzite with sandy soil

5.10 15.0 Light purple to reddish, highly fractured and slightly weathered

rock of phyllite with quartzite (WEAK BED ROCK)

D 5

0.0 1.00 Light grey medium dense gravel mix sandy soil

1.00 2.00 Radish brown dense sandy soil with fragments of phyllite

2.00 3.00 Light grey dense sand mix gravel of weathered phyllite and

quartzite

3.00 5.00 Radish brown to pale yellow very dense sandy soil with

fragments of phyllite

5.00 10.00 Brownish grey to pale yellow highly weathered phyllitic rock

(WEAK ROCK BED)

D - 7

0.0 1.95 Brownish grey to radish loose to medium dense silty sand with

clay and small fragments of phyllite

1.95 3.00 Light Brown medium dense to very dense sandy silt with

gravel of fine grained quartzite and phyllite

3.00 10.00 Brownish grey to reddish slightly weathered and fractured rock

of phyllite with fine grained quartzite (WEAK BED ROCK)

D - 8

0.0 4.00 Light brownish grey loose to medium dense silty sand with

fragments of phyllite (size of pebble, cobble and boulder) with

clayey traces

4.00 10.00 Light grey slightly weathered and fractured phyllitic rock

(WEAK BED ROCK)

D - 9

0.00 2.00 Light raddhish to grey medium dense silty clay sand with

weathered phyllite with quartzite (pebble to cobble)

2.00 10.00 Light grey fresh to highly weathered fractured phyllitic rock

bed (WEAK BED ROCK)





2.5 Analysis of Allowable Bearing Pressure

The allowable bearing pressure (qa) is the maximum pressure that can be imposed on the

foundation soil taking into consideration the ultimate bearing capacity of the soil and the tolerable

settlement of the structure. Analysis to determine the ultimate bearing capacity and the pressure

corresponding to a specified maximum settlement were performed and the minimum pressure

obtained from the two analyses were adopted as the allowable bearing pressure.

2.5.1 Correlation between SPT and DCPT

Nc values of different bore holes are presented in the corresponding borelogs.

The dynamic cone resistance is correlated with the SPT N number as given below:

Nc = 1.50 N for depths up to 3 m

Nc= 1.75 N for depths 3 to 6 m

Nc= 2.00 N for depths greater than 6 m

2.5.2 SPT correction

The SPT values have been corrected in accordance with the proposal of Skempton, (1986) and Liao

and Whitman (1987) as outlined below with consideration of field procedure, hammer efficiency,

borehole diameter, sample and rod length.

Correction of SPT N-value using the relation after Skempton, 1986




N60 = Em CB CS CR N/0.60

Where: N60 = SPT N value corrected for field procedure

Em = Hammer Efficiency

CB = borehole diameter correction

CS = Sample Correction

CR = rod length correction

N = SPT N value recorded in the field

The correction factors taken are :

Em =0.55 for hand drop hammer, due to lack of true verticalness and proper speed of SPT blow

CB = 1.0 for 65 mm to 115 mm dia. Borehole,

Cs =1.0 for standard sampler,

CR =0.7 for rod length 0.00 - 2.99,

=0.75 for rod length 3.00 - 3.99 m,

=0.85 for rod length 4.00 - 5.99 m,

=0.95 for rod length 6.00 - 9.99 m,

=1 for rod length beyond 10.00 m,

Correction for overburden

Correction of corrected N60 field value for overburden pressure using the relation after Liao and

Whitman, 1987

(N1)60 = N60 (100kPa/'z)

Where: N60 = SPT N value corrected for field procedure

(N1)60 = SPT N-value corrected for field procedures and overburden stress

Similarly,

The correction for values of N should be made for the field SPT values for depths. Modified

correction in 1974, peck, Hanson and Thornburn with suggested standard pressure of 100 kN/m2

corresponding to a depth of 5 m of soil with bulk density 20kN/m2 can be represented by the

following equation:

(N1)60 = N60 Cn




Cn=0.77 log (2000/p0)

Where, p0 is effective overburden pressure in kN/m2.

2.5.3 Allowable Bearing Pressure based on Ultimate Bearing Capacity

Since the soil in the vicinity of the foundation level has been found to be granular or non-plastic,

cohesion less sandy gravel with pebble and cobble, the allowable bearing capacity has been

analyzed using the angle of friction and cohesion values from direct shear test results. Empirical

formula of Indian Standard IS 6403:1981 is applicable for this type of soils has been used to obtain

the allowable bearing pressure with safety factor equal to 3.

qa = c Nc sc dc ic+q (Nq-1) sq dq iq+1/2*B N s d i W (2.1)

Where: qa = net allowable bearing pressure, t/m2

C = cohesion in t/m2

Nc, Nq, N = Bearing capacity factors

sc, sq, s = Shape factors,

dc, dq, d = Depths factors

ic, iq, i = Inclination factors

q = Effective surcharge at the base level of foundation in t/m2

B = Width of footing in m,

= Bulk unit weight of soil sample in t/m3

W = Correction factor for location of water table

The values of Nc, Nq, and N may be obtained from Table 2.

Table 2, Bearing Capacity Factor

Angle of friction (degree) Nc Nq N

0 5.14 1 0

5 6.49 1.57 0.45

10 8.35 2.47 1.22

15 10.98 3.94 2.65

20 14.83 6.4 5.39

25 20.72 10.66 10.88

30 30.14 18.4 22.4

35 46.12 33.3 48.03

40 75.31 64.2 109.41

45 138.88 134.88 271.76

50 266.89 319.07 762.89

The values of sc, sq, and s may be obtained from Table 3.




Table 3, Shape Factors

Shape of Footing Sc Sq S

Square 1.3 1.3 1.3

The depth factors shall be as

dc,= 1+0.2 Df/BN

dq,= d = 1 for 10

The inclination factor shall be as under

ic = iq = (1-/90)2 and i = (1-/)

2

W (effect of water table)

If water table is likely to permanently remains at or below a depth of (Df+B) beneath the ground

level surrounding the footing then W = 1.

If the water table is located at depth Df or likely to rise to the base of the footing or above then the

value of W shall be taken as 0.5.

If the water table is likely to permanently got located at depth Df




Es = Modulus of elasticity of sand

Iz = Strain influence at depth z

Approximate relationship between Cone penetration resistance (qc) and SPT value (N1)60 with

Stress- Strain Modulus Es (Bowles, 1982) are given below:

qc/N Es (kN/m2) Soil type

300-800 2.5 qc Coarse sand with small gravel

2.5.5 Pile Foundation

Qu1 = siDi

n

li

qDrrp AKPNPNDA .tan2

1

Qu2 = sip AcCNcA .

Qu = Qu1 + Qu2

Where,

Ap = Cross sectional area of pile toe

D = Pile Stem diameter

= effective unit weight of soil at pile toe

PD = effective over burden pressure at pile toe

N & Nq = bearing capacity factor depending upon the angle of internal friction at toe.

n

li = summation of n layers in which pile is installed.

= angle of internal friction

K = coefficient of earth pressure

sin1

sin1

Pdi = effective over burden pressure for the i th layer where i varies from 1 to n.

= angle of wall friction between the pile

Asi = surface area of pile stem in the i th layer

c = Cohesion of Soil

Nc = Skemption factor and = Adhesion Factor




For working out a safe load carrying capacity of the pile, a factor of safety of 2.5 is adopted.

BASED ON MEYERHOFS

Qutip =120 N Ab, KN and Qushaft=Naverage Asi, KN

For working out a safe load carrying capacity of the pile, a factor of safety of 2.5 and 4 is adopted.

BASED ON DECOURT, 1995

Qutip=Kb Naveragebase Ab, KN and Qushaft= (2.8 N60 + 10) Asi, KN

Where, = 0.5 to 0.6 for sandy and 1 for clayey

Kb

Soil Type Kb

Sand 165

Sandy Silt 120

Clayey Silt 100

Clay 80

The bearing capacity of a single pile is to be determined from loading or failure test of a pile during

construction works. The purpose of the test is one or more of the following:

to establish criteria for installation of working piles

to establish settlement of working load

to get an idea of the suitability of the pile for a particular purpose

to determine the safe load capacity

2.5.6 Estimation of Bearing Capacity (Rock/Boulder)

Foundation on Intact Rock

When the loaded area is same or slightly less than the spacing of open vertical joints, for a footing

resting at the surface or near the surface or a pile, the ultimate bearing capacity, qult is,

qult=c

If the loaded area is much smaller, i.e. less than 1/5th of the spacing of open vertical joints as may

be in the case of pile, the ultimate bearing capacity will be greater than ci and is obtained by

considering one of the theories adopted for soils, i.e Terzaghis,

qult = 1.2 c Nc + 0.5 BNr

Where,

c=cohesion intercept of intact rock

B=width or diameter of the loaded area and =density of rock




Nc and Nr = bearing capacity factors, depend on the friction angle of intact rock

The rupture surface may develop on one side, due to defects in the rock. Therefore qult may be

taken as 50% of the value given by above equation. Studies of model footings on rock-like material

have shown (Ramamurthy 1995), that qult may be taken as 1.4 ci.

If the vertical joints are tight, even in this case qult will be greater than ci; the qult may be obtained

by enhancing ci by considering the influence of confinement, if the joint sets dip on either side, the

qult will be greater than cj, compressive strength and shear stresses developed on the different

combination of joint planes with one of the joint planes dipping under the loaded area from its one

of the edges.

Alternatively, the qult may be estimated by enhancing the compressive strength of the rock mass, cj

(Ramamurthy 1995) using joint factor, jf. it has been concluded from model studies that qult of rock

mass for surface footing could be taken as 1.7cj; cj is estimated from joint factor, this may take

care of rotation of some of the blocks.

Heavily Fractured Rock

When the rock mass is heavily fractured (i.e. c = 0) and the strip foundation is to be located at

some depth Df, the ultimate bearing capacity have been calculated by considering rupture planes

under the footing and the surrounding mass (Pauker 1889),

qult= Df tan4

Where

Df = depth of foundation, = density of rock mass and = friction angle, degrees.

For surface footings, above equation gives qult = 0 as in the case of gravelly soil.

By considering crushing of rock under the footing and with the confining pressure from the sides

acting equal to ci, Goodman (1989) suggested

qult=ci or ci (N+1)

Where, is the friction angle of the intact rock and N = tan2 , ignoring its cohesion

component. For a value of = 30, above equation will give qult four times the unconfined

compressive strength for crushing of rock under a symmetrical condition of side confinement.

The influence of size of footing with respect to the spacing of joints (horizontal and vertical),

Bishnoi (1968) showed for open vertical joints that

qult = ci




Where, s = spacing of joints and B = width of footing.

When s = B, qult = ci and when the spacing between the open vertical joints increases to five times

the width, the qult will increase to 3.9 ci for = 30. The value will increase the qult above

equation is applicable when >0. With the tilting failure of footing, qult will be 1.95ci.

As per above equations the qult will generally be high for rock mass. The actual values will be

lower mainly due to the rotation and sliding of some blocks within the zone of influence. with the

uncertainty involved in the estimation of and ci, it is always desirable to adopt larger factor of

safety or conservative values of ci and .

Bearing Capacity with Shape Factors

For estimating the ultimate bearing capacity of a strip footing resting on rock surface, Coates

(1970) suggested a simplified expression in the following form by considering failure along two

planes,

qult=c Nc + q Nq + 0.5 B N

Where,

c = cohesion of rock and q = surcharge loading around the footing

B = width of footing and = density of rock

Nc = , Nq = tan6 and Nr = Nq + 1

= friction angle of rock.

This equation gives good results for varying from 0 to 45 and the results are comparable with

Terzaghis equation for the bearing capacity of strip footing. For square and circular footings on

rocks, the term Nc will be taken as,

Nc=7 tan4

If the rupture surface is not likely to develop on either side of the footing due to site conditions or

loading and the failure is likely to occur on one side, only 50% of qult will have to be taken into

consideration.

The shear strength parameters, c and for rock could be evaluated by conducting two plate -

bearing tests at the surface of the rock. The size of the plate should match with the joint system,

usually less than 1 * 1 m2 sizes. The results obtained could be applied to a larger loaded area.

A more rigorous expression by Terzaghi (1943) may be adopted for strip loading

qult = c Nc sc + Df Nq + 0.5 B N sq




The values of Nc, Nq and Nr as per Terzaghi are given in Table 4, for various values of

considering general shear failure. The values of sc for circular and square footings are 1.2 and sq

for square footing = 0.8 and for circular footing = 0.6.

When no test data of c and is available, RQD from bore log may be adopted with caution to

estimate the ultimate bearing capacity from

qult = ci(RQD/100)2

Where, ci = compressive strength of intact specimen.

In most cases, (RQD/100)2 may very between 1/3 and 1/10; for lower values of RQD (




Project : Soil Investigation of Proposed Building Foundation Hole No.: D1 ~ D9

Client : FLIK NEPAL RESORT PET LTD Station (Km+m)

Location : SARANKOT, Kaski, Nepal Ground Water GL, m :

Identification = Modeled Strata Depth of exploration, m:

Clayey layer exist ; fro m 0.0 m to 0.0 m 0.0 m to 0.0 m 0.0 m to 0.0 m 0.0 m to 0.0 m 0.0 m to 0.0 m Designed Ground Water GL, m :

Hammer energy Correction, Er: 60 % Scour Depth, m: 1.50

Drilling Method : ROTARY r Soil Condition : = Drain Void Ratio (e) = 0.730324 Depth of Pile Top from NGL, m =

Depth,

m

Is

there

Silt

or

not*

Part of

soil,

Sandy or

Clayey

Design

(Equivalent)

SPT N-

Value

Bulk

Density,

t/m3

D50

from

Seive

analysis

Liquid

Limit,

LL (%)

N value

after

Dilatancy

Correction Ncoorected

Field

Based

,

Field

Based C,

t/m2

Lab

Based

,

Lab

Based c,

t/m2

PHI

,

Design

,

Cohesion,

T/m2

Design c,

KN/m2

Design

Cc,

KN/m3

Dra

inag

e C

onditio

n

**

0 n Sand 5 1.75 0.5 0 5 6 23 - 30 (1) 27 27 - 1.0 - D E

1.5 n Sand 6 1.85 0.50 - 6 7 24 4.4 31 - 27 > 30 4.4 - - D E

3 n Sand 17 1.85 0.50 - 17 18 29 11.3 32 - 30 > 31 11.3 - - D E

4.5 n Sand 18 1.85 0.50 - 18 20 30 12.5 32 - 31 > 31 12.5 - - D E

6 n Sand 23 1.85 0.50 - 23 26 32 16.3 33 - 32 > 32 16.3 - - D E

7.5 n Sand 33 1.85 1.00 - 33 35 35 21.9 34 - 34 > 34 21.9 - - D E

9 n Sand 41 1.85 1.00 - 41 42 37 26.3 35 - 36 > 36 26.3 - - D E

10.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D E

12 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D E

13.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D E

15 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D E

16.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

18 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

19.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

21 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

22.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

24 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

25.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

27 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

28.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

30 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

31.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

33 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

34.5 n Sand > 50 > 2.00 > 1 - 50 50 39 31.3 > 37 - 38 > 38 31.3 - - D A

* n = NO * y = YES ** E = Estimated ** A = Assumed D Drain U Undrain

15.0

0.00

1.5

1.5

DESIGN INPUT DATA

NO




BEARING CAPACITY OF SHALLOW (OPEN) FOUNDATION


Client : FLIK NEPAL RESORT PET LTD Station (Km+m) 0

Location : SARANKOT, Kaski, Nepal Ground Water GL, m : NO

Identification = Modeled Strata Designed Ground Water GL, m : 0

Width

of

footing

(B), m

Length

of

footing

(L), m

Area of

footing

(A), m2

Depth

of

water

table

(Dw),

m

Depth

of

Footing

(Df), m

Angle

of

friction

(),

Cohesion

of soil

,

kg/cm2

unit

weight

of soil

(),

kg/m3 N"

Effective

Surcharge

at base of

footing (q),

kg/cm2

Nq Ny

1.0 29 0.00 0.002 37.9 0.08 16.45 12.85

1.5 30 0.00 0.002 29.7 0.13 18.40 15.07

2.0 30 0.00 0.002 29.7 0.17 18.40 15.07

2.5 31 0.00 0.002 22.7 0.22 21.00 18.03

3.0 31 0.00 0.002 22.7 0.26 21.00 18.03

4.0 31 0.00 0.002 22.7 0.35 21.00 18.03

5.0 31 0.00 0.002 22.7 0.44 21.00 18.03

6.0 32 0.00 0.002 16.8 0.61 23.50 21.09

7.0 33 0.00 0.002 11.9 0.71 26.50 24.84

8.0 35 0.00 0.002 4.7 0.82 33.30 33.93

9.0 36 0.00 0.002 2.3 0.92 37.20 39.45

Sq Sc S dq dc d iq ic

1.48 1.59 0.60 1.15 1.20 1.00 1.00 1.00 0.5 26.49 3.0 1.0 8.25 10.00

1.50 1.61 0.60 1.22 1.30 1.00 1.00 1.00 0.5 48.00 3.0 1.5 15.07 17.85

1.50 1.61 0.60 1.29 1.40 1.00 1.00 1.00 0.5 66.07 3.0 2.0 20.79 24.49

1.52 1.65 0.60 1.25 1.36 1.00 1.00 1.00 0.5 91.73 3.0 2.5 29.03 33.66

1.52 1.65 0.60 1.28 1.39 1.00 1.00 1.00 0.5 111.11 3.0 3.0 35.19 40.74

1.52 1.65 0.60 1.31 1.44 1.00 1.00 1.00 0.5 150.37 3.0 4.0 47.66 55.06

1.52 1.65 0.60 1.34 1.48 1.00 1.00 1.00 0.5 189.96 3.0 5.0 60.24 69.49

1.53 1.65 0.60 1.34 1.50 1.00 1.00 1.00 0.5 302.26 3.0 6.0 96.75 108.75

1.54 1.69 0.60 1.35 1.52 1.00 1.00 1.00 0.5 401.45 3.0 7.0 129.15 143.15

1.57 1.72 0.60 1.34 1.53 1.00 1.00 1.00 0.5 582.12 3.0 8.0 188.71 204.71

1.59 1.73 0.60 1.33 1.54 1.00 1.00 1.00 0.5 735.08 3.0 9.0 239.03 257.03

Depth

of

Footing

(Df), m

Net

Allowable

Bearing

Capacity of

Soil (qna),

t/m2

Gross

Allowable

Bearing

Capacity

of Soil

(qga), t/m2

36.05

38.50

46.12

51.15

Factor

of

Safety

Shape Factor Depth factor Inclination factor

Water

table

correction

w'

Ultimate

Bearing

Capacity

of Soil

(qc), t/m2

Nc

2.0 2.0 4 0.0

28.04

32.50

30.14

30.14

32.50

32.50

32.50







Identification = Modeled Strata Depth of exploration, m: 15

Depth of Foundation D = 1.50 m Designed Ground Water GL, m :0

Width of Foundation B = 2.00 m Scour Depth, m: 1.5

Length of Foundation L = 2.00 m Depth of Pile Top from NGL, m =1.5

Allowable Bearing Capacity (Shear) of soil for designated foundation; 15.1 t/m2

2

Assumed Safe Bearing Capacity of foundation (Shear or Settlement), 15.1 t/m2

In case of 2 m wide, Shallow Fondation resting on 1.5 m below the NGL effective depth =5.5 m

Depth,

m

Bulk

Density

(gamma)

t/m3

Ratio

of qc/N

qc,

KN/m2

Es,

KN/m2

Z to

the

center

of

layer, m

Iz at center

of layer Iz/Es * Z

Settlement,

Ss

1.5 1.5 to 3.0 1.85 7 6.3 4410 11025 0.75 0.400 0.000054 9.5014

3 3.0 to 3.0 1.85 18 6.3 11340 28350 1.50 0.417 0.000000 0.0000

4.5 3.0 to 4.5 1.85 20 6.3 12600 31500 2.25 0.292 0.000014 2.4248

6 4.5 to 6.0 1.85 26 6.3 16380 40950 3.75 0.042 0.000002 0.2665

7.5 6.0 to 7.5 1.85 35 8 28000 70000 5.25 -0.208 0.000000 0.0000

9 7.5 to 9.0 1.85 42 8 33600 84000 6.75 -0.458 0.000000 0.0000

10.5 9.0 to 10.5 2.00 50 8 40000 100000 8.25 -0.708 0.000000 0.0000

12 10.5 to 12.0 2.00 50 8 40000 100000 9.75 -0.958 0.000000 0.0000

13.5 12.0 to 13.5 2.00 50 8 40000 100000 11.25 -1.208 0.000000 0.0000

15 13.5 to 15.0 2.00 50 8 40000 100000 12.75 -1.458 0.000000 0.0000

16.5 15.0 to 16.5 2.00 50 8 40000 100000 14.25 -1.708 0.000000 0.0000

18 16.5 to 18.0 2.00 50 8 40000 100000 15.75 -1.958 0.000000 0.0000

19.5 18.0 to 19.5 2.00 50 8 40000 100000 17.25 -2.208 0.000000 0.0000

21 19.5 to 21.0 2.00 50 8 40000 100000 18.75 -2.458 0.000000 0.0000

22.5 21.0 to 22.5 2.00 50 8 40000 100000 20.25 -2.708 0.000000 0.0000

24 22.5 to 24.0 2.00 50 8 40000 100000 21.75 -2.958 0.000000 0.0000

25.5 24.0 to 25.5 2.00 50 8 40000 100000 23.25 -3.208 0.000000 0.0000

Effective Bulk Density = 1.85 Settlement in Sandy layer = 12.2 mm

Depth correction factor C1= 0.89 0.89 Creep Factor C2= 1.6 Assuming 100 yrs for settlement

Now Settlement prediction on cohesionless soil with designed load; 12.2 mm

In case of 2 m wide, Shallow Fondation resting on 1.5 m below the NGL effective depth for clayey soil =5.5 m

Depth,

m

Compression

Index, cc

Design

Compression

Index, cc

Void

Ratio,

e0 sigma/z P P0 H

Settlement,

Sc

1.5 1.5 to 3.0 0.00 0.00 0.73 0.999 15.1 2.8 1.50 0.000000

3 3.0 to 3.0 0.00 0.00 0.73 0.508 7.7 5.6 1.50 0.000000

4.5 3.0 to 4.5 0.00 0.00 0.73 0.194 2.9 8.3 1.50 0.000000

6 4.5 to 6.0 0.00 0.00 0.73 0.096 1.4 11.1 1.50 0.000000

7.5 6.0 to 7.5 0.00 0.00 0.73 0.065 1.0 13.9 1.50 0.000000

9 7.5 to 9.0 0.00 0.00 0.73 0.000 0.0 16.7 1.50 0.000000

10.5 9.0 to 10.5 0.00 0.00 0.73 0.000 0.0 19.7 1.50 0.000000

12 10.5 to 12.0 0.00 0.00 0.73 0.000 0.0 22.7 1.50 0.000000

13.5 12.0 to 13.5 0.00 0.00 0.73 0.000 0.0 25.7 1.50 0.000000

15 13.5 to 15.0 0.00 0.00 0.73 0.000 0.0 28.7 1.50 0.000000

16.5 15.0 to 16.5 0.00 0.00 0.73 0.000 0.0 31.7 1.50 0.000000

Settlement in clayey layer=

Limiting Settlement as per Code; 40.00 mm 0

Predicted Total Settlement with designated load; 12.2 mm

0.0 mm

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

Semi Empirical Method by Schmertmann and Hartmann

Soil Layer, m N- Corrected

Settlement Analysis of Open (SHALLOW) Foundation

0.0000000

Soil Layer, m Predicted Settlement, Sc

0.0000000

0.0000000

Semi Empirical Method Based on Clayey layer




BEARING CAPACITY OF SHALLOW (OPEN) FOUNDATION




Identification = Modeled Strata Designed Ground Water GL, m : 0

Width

of

footing

(B), m

Length

of

footing

(L), m

Area of

footing

(A), m2

Depth

of

water

table

(Dw),

m

Depth

of

Footing

(Df), m

Angle

of

friction

(),

Cohesion

of soil

,

kg/cm2

unit

weight

of soil

(),

kg/m3 N"

Effective

Surcharge

at base of

footing (q),

kg/cm2

Nq Ny

1.0 34 0.00 0.002 7.9 0.08 29.70 29.04

1.5 35 0.00 0.002 4.7 0.13 33.30 33.93

2.0 35 0.00 0.002 4.7 0.17 33.30 33.93

2.5 35 0.00 0.002 4.7 0.22 33.30 33.93

3.0 35 0.00 0.002 4.7 0.26 33.30 33.93

4.0 36 0.00 0.002 2.3 0.35 37.20 39.45

5.0 36 0.00 0.002 2.3 0.44 37.20 39.45

6.0 37 0.00 0.002 0.7 0.61 42.60 47.02

7.0 37 0.00 0.002 0.7 0.71 42.60 47.02

8.0 38 0.00 0.002 0.0 0.82 48.90 56.14

9.0 38 0.00 0.002 0.0 0.92 48.90 56.14

Sq Sc S dq dc d iq ic

1.56 1.71 0.60 1.02 1.03 1.00 1.00 1.00 0.5 81.42 3.0 1.0 26.56 28.31

1.57 1.72 0.60 1.03 1.04 1.00 1.00 1.00 0.5 125.55 3.0 1.5 40.92 43.70

1.57 1.72 0.60 1.03 1.05 1.00 1.00 1.00 0.5 149.70 3.0 2.0 48.67 52.37

1.57 1.72 0.60 1.04 1.07 1.00 1.00 1.00 0.5 174.23 3.0 2.5 56.54 61.16

1.57 1.72 0.60 1.05 1.08 1.00 1.00 1.00 0.5 199.16 3.0 3.0 64.54 70.09

1.59 1.73 0.60 1.07 1.11 1.00 1.00 1.00 0.5 283.54 3.0 4.0 92.05 99.45

1.59 1.73 0.60 1.08 1.13 1.00 1.00 1.00 0.5 342.54 3.0 5.0 111.10 120.35

1.60 1.76 0.60 1.10 1.16 1.00 1.00 1.00 0.5 540.58 3.0 6.0 176.19 188.19

1.60 1.76 0.60 1.11 1.19 1.00 1.00 1.00 0.5 624.60 3.0 7.0 203.53 217.53

1.62 1.79 0.60 1.12 1.21 1.00 1.00 1.00 0.5 823.20 3.0 8.0 269.07 285.07

1.62 1.79 0.60 1.14 1.24 1.00 1.00 1.00 0.5 924.87 3.0 9.0 302.29 320.29

Depth

of

Footing

(Df), m

Net

Allowable

Bearing

Capacity of

Soil (qna),

t/m2

Gross

Allowable

Bearing

Capacity

of Soil

(qga), t/m2

56.30

56.30

62.00

62.00

Factor

of

Safety

Shape Factor Depth factor Inclination factor

Water

table

correction

w'

Ultimate

Bearing

Capacity

of Soil

(qc), t/m2

Nc

15.0 15.0 225 0.0

42.08

51.15

46.12

46.12

46.12

46.12

51.15







Identification = Modeled Strata Depth of exploration, m: 15

Depth of Foundation D = 2.00 m Designed Ground Water GL, m :0

Width of Foundation B = 15.00 m Scour Depth, m: 1.5

Length of Foundation L = 15.00 m Depth of Pile Top from NGL, m =1.5

Allowable Bearing Capacity (Shear) of soil for designated foundation; 48.7 t/m2

2

Assumed Safe Bearing Capacity of foundation (Shear or Settlement), 46.9 t/m2

In case of 15 m wide, Shallow Fondation resting on 2 m below the NGL effective depth =32 m

Depth,

m

Bulk

Density

(gamma)

t/m3

Ratio

of qc/N

qc,

KN/m2

Es,

KN/m2

Z to

the

center

of

layer, m

Iz at center

of layer Iz/Es * Z

Settlement,

Ss

2 2.0 to 3.5 1.85 7 6.3 4410 11025 0.75 0.140 0.000019 12.6240

3.5 3.5 to 3.5 1.85 18 6.3 11340 28350 1.50 0.180 0.000000 0.0000

5 3.5 to 5.0 1.85 20 6.3 12600 31500 2.25 0.220 0.000010 6.9432

6.5 5.0 to 6.5 1.85 26 6.3 16380 40950 3.75 0.300 0.000011 7.2831

8 6.5 to 8.0 1.85 35 8 28000 70000 5.25 0.380 0.000008 5.3968

9.5 8.0 to 9.5 1.85 42 8 33600 84000 6.75 0.460 0.000008 5.4441

11 9.5 to 11.0 2.00 50 8 40000 100000 8.25 0.483 0.000007 4.8050

12.5 11.0 to 12.5 2.00 50 8 40000 100000 9.75 0.450 0.000007 4.4736

14 12.5 to 14.0 2.00 50 8 40000 100000 11.25 0.417 0.000006 4.1423

15.5 14.0 to 15.5 2.00 50 8 40000 100000 12.75 0.383 0.000006 3.8109

17 15.5 to 17.0 2.00 50 8 40000 100000 14.25 0.350 0.000005 3.4795

18.5 17.0 to 18.5 2.00 50 8 40000 100000 15.75 0.317 0.000005 3.1481

20 18.5 to 20.0 2.00 50 8 40000 100000 17.25 0.283 0.000004 2.8167

21.5 20.0 to 21.5 2.00 50 8 40000 100000 18.75 0.250 0.000004 2.4854

23 21.5 to 23.0 2.00 50 8 40000 100000 20.25 0.217 0.000003 2.1540

24.5 23.0 to 24.5 2.00 50 8 40000 100000 21.75 0.183 0.000003 1.8226

26 24.5 to 26.0 2.00 50 8 40000 100000 23.25 0.150 0.000002 1.4912

Effective Bulk Density = 1.85 Settlement in Sandy layer = 75.0 mm

Depth correction factor C1= 0.96 0.96 Creep Factor C2= 1.6 Assuming 100 yrs for settlement

Now Settlement prediction on cohesionless soil with designed load; 75.0 mm

In case of 15 m wide, Shallow Fondation resting on 2 m below the NGL effective depth for clayey soil =32 m

Depth,

m

Compression

Index, cc

Design

Compression

Index, cc

Void

Ratio,

e0 sigma/z P P0 H

Settlement,

Sc

2 2.0 to 3.5 0.00 0.00 0.73 0.999 46.9 3.7 1.50 0.000000

3.5 3.5 to 3.5 0.00 0.00 0.73 0.958 44.9 6.5 1.50 0.000000

5 3.5 to 5.0 0.00 0.00 0.73 0.921 43.2 9.3 1.50 0.000000

6.5 5.0 to 6.5 0.00 0.00 0.73 0.855 40.1 12.0 1.50 0.000000

8 6.5 to 8.0 0.00 0.00 0.73 0.773 36.3 14.8 1.50 0.000000

9.5 8.0 to 9.5 0.00 0.00 0.73 0.707 33.1 17.6 1.50 0.000000

11 9.5 to 11.0 0.00 0.00 0.73 0.631 29.6 20.6 1.50 0.000000

12.5 11.0 to 12.5 0.00 0.00 0.73 0.550 25.8 23.6 1.50 0.000000

14 12.5 to 14.0 0.00 0.00 0.73 0.469 22.0 26.6 1.50 0.000000

15.5 14.0 to 15.5 0.00 0.00 0.73 0.395 18.5 29.6 1.50 0.000000

17 15.5 to 17.0 0.00 0.00 0.73 0.350 16.4 32.6 1.50 0.000000

Settlement in clayey layer=

Limiting Settlement as per Code; 75.00 mm 0

Predicted Total Settlement with designated load; 75.0 mm

0.0 mm

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

0.0000000

Semi Empirical Method by Schmertmann and Hartmann

Soil Layer, m N- Corrected

Settlement Analysis of Open (SHALLOW) Foundation

0.0000000

Soil Layer, m Predicted Settlement, Sc

0.0000000

0.0000000

Semi Empirical Method Based on Clayey layer




CAPACITY OF CAST IN-SITU BORED PILE

Project : Soil Investigation of Proposed Building Foundation Hole No. = 0

Client : FLIK NEPAL RESORT PET LTD Excavation Depth, m = 4.0 Station (Km+m) = 0+000

Location : SARANKOT, Kaski, Nepal Depth of Pile Top from NGL, m = 4.0 Ground Water GL, m = NO

Identification = Modeled Strata Drill with Bentonite Slurry 7200 Depth of exploration, m = 15.0

Length of Pile (L), m = 10.0 Base of the pile lies on = 14.0 Designed Ground Water GL, m =0.0

Diameter of Pile (D), mm = 800 Probable Liquefaction depth, m = 1.5 Scour Depth, m = 4.0

Area of Pile X-Section, m2

= 0.503 End Bearing Resistance, qt, Tons = 110.8 Shaft Bearing Resistance, qs, Tons = 19.3

Allowable Load Carrying Capacity of Pile (Q), Tons = 130.2

Load Capacity of Pile @ liquefaction (Qliq), Tons = 216.9

Depth, mEffective

Thickness, m

Design

,

Design c,

KN/m2

Effective

Surcharge

Pressure,

t/m2

Surface

area (Asi),

m2

N-value

End Bearing

Resistance

(Qupc), Tonnes

Skin Bearing

Resistance

(Qusc), Tonnes

End

Bearing

Resistance

Qups, Tonnes

Skin

Bearing

Resistance

(Quss), Tonnes

End

Bearing

Resistance

(Qus), Tonnes

Shaft

Bearing

Resistance

(Qup), Tonnes

End Bearing

Resistance

(Qus), Tonnes

Shaft Bearing

Resistance

(Qus), Tonnes

End Bearing

Resistance qt,

t/m2

Shaft

Bearing

Resistance

qs, t/m2

0 - 27 - 0.000 - 6 - - - - - - - - - -

1.5 - 27 - 0.578 - 7 - - 4.1 - 19.6 - 27.0 - 8.1 -

3 - 31 - 1.395 - 20 - - 11.2 - 31.7 - 43.5 - 22.2 -

4.5 1.5 31 - 2.513 3.8 22 - - 20.0 1.1 37.7 6.6 51.8 4.5 39.9 0.3

6 1.5 33 - 3.649 3.8 29 - - 34.2 1.8 51.3 8.7 70.5 5.9 68.1 0.5

7.5 1.5 35 - 4.793 3.8 39 - - 56.3 2.5 63.3 11.8 87.1 7.2 111.9 0.7

9 1.5 36 - 5.940 3.8 46 - - 81.7 2.7 72.4 13.9 99.5 8.2 162.5 0.7

10.5 1.5 38 - 7.090 3.8 50 - - 110.8 3.5 75.4 15.1 103.7 8.5 220.3 0.9

12 1.5 38 - 8.241 3.8 50 - - 110.8 4.0 75.4 15.1 103.7 8.5 220.4 1.1

13.5 1.5 38 - 8.907 3.8 50 - - 110.8 3.6 75.4 15.1 103.7 8.5 220.5 1.0

15 1.5 38 - 9.000 3.8 50 - - 110.9 3.7 75.4 15.1 103.7 8.5 220.6 1.0

16.5 1.5 38 - 9.076 3.8 50 - - 110.9 3.7 75.4 15.1 103.7 8.5 220.6 1.0

18 1.5 38 - 9.140 3.8 50 - - 110.9 3.7 75.4 15.1 103.7 8.5 220.6 1.0

19.5 1.5 38 - 9.194 3.8 50 - - 110.9 3.8 75.4 15.1 103.7 8.5 220.7 1.0

21 1.5 38 - 9.240 3.8 50 - - 110.9 3.8 75.4 15.1 103.7 8.5 220.7 1.0

22.5 1.5 38 - 9.280 3.8 50 - - 111.0 3.8 75.4 15.1 103.7 8.5 220.7 1.0

24 1.5 38 - 9.315 3.8 50 - - 111.0 3.8 75.4 15.1 103.7 8.5 220.8 1.0

25.5 1.5 38 - 9.346 3.8 50 - - 111.0 3.8 75.4 15.1 103.7 8.5 220.8 1.0

27 1.5 38 - 9.373 3.8 50 - - 111.0 3.8 75.4 15.1 103.7 8.5 220.8 1.0

28.5 1.5 38 - 9.398 3.8 50 - - 111.0 3.8 75.4 15.1 103.7 8.5 220.8 1.0

30 1.5 38 - 9.420 3.8 50 - - 111.0 3.9 75.4 15.1 103.7 8.5 220.8 1.0

31.5 1.5 38 - 9.440 3.8 50 - - 111.0 3.9 75.4 15.1 103.7 8.5 220.8 1.0

33 1.5 38 - 10.089 3.8 50 - - 119.0 4.1 75.4 15.1 103.7 8.5 236.7 1.1

34.5 1.5 38 - 12.416 3.8 50 - - 119.0 5.1 75.4 15.1 103.7 8.5 236.7 1.3

Indian Standard Meyerhof Decourt Method




Output

Shallow Foundation

Breaking strength of sample (boulder)

Point Load Index (Mpa) 0.6 to 2.6

Rock/Boulder Type Phyllitic with quartzite

Rock Strength Very weak to weak

Assumed Uniaxial Compressive Strength (Mpa) 15 to 65.0

RQD




Width of Square Footing,

m


m


m

6.0 7.0 10.0

1 12.2 12.2 14.5 14.5 18.3 15.6

1.5 21.1 15.6 21.5 15.6 26.1 15.6

2 27.1 15.6 27.4 15.6 36.9 15.6

2.5 33.3 15.6 37.5 15.6 44.2 15.6

3 44.4 15.6 44.5 15.6 58.2 15.6

4 59.5 15.6 66.6 15.6 84.8 15.6

5 95.1 15.6 93.9 15.6 100.0 15.6

6 151.1 15.6 140.0 15.6 108.9 15.6

7 158.9 15.6 143.1 15.6 112.3 15.6

8 178.6 15.6 158.2 15.6 121.2 15.6

9 185.1 15.6 163.6 15.6 125.5 15.6


m Width of Square Footing,

m Width of Square Footing,

m

15.0 20.0 30.0

1 28.3 15.6 35.7 15.6 27.8 15.6

1.5 43.7 15.6 41.1 15.6 31.0 15.6

2 50.6 15.6 43.2 15.6 33.6 15.6

2.5 52.6 15.6 45.1 15.6 35.4 15.6

3 64.7 15.6 52.9 15.6 39.9 15.6

4 68.2 15.6 56.7 15.6 43.7 15.6

5 75.9 15.6 62.3 15.6 48.3 15.6

6 82.0 15.6 67.8 15.6 53.2 15.6

7 85.8 15.6 71.7 15.6 57.0 15.6

8 91.4 15.6 76.4 15.6 61.2 15.6

9 95.6 15.6 80.4 15.6 65.2 15.6

Deep Foundation (Cast In-Situ Bored Concrete Pile)

BEARING CAPACITY OF SINGLE VERTICAL PILE FOUNDATION GENERAL (Static)

Diameter of Pile, mm 800

Length of pile, m 10.0

Bearing Capacity, KN 1302

BEARING CAPACITY OF SINGLE VERTICAL PILE FOUNDATION (DYNAMIC)

Diameter of Pile, mm 800

Length of pile, m 10.0

Bearing Capacity, KN 2170




CAPACITY OF CAST IN-SITU BORED PILE ( for > 710 mm)

Depth, mEffective

Thickness, mDesign ,

Design c,

KN/m2

End Bearing

Resistance qt, t/m2

Shaft Bearing

Resistance qs, t/m2

0 - 27 - - -

1.5 - 27 - 8.1 -

3 - 31 - 22.2 -

4.5 1.5 31 - 39.9 0.3

6 1.5 33 - 68.1 0.5

7.5 1.5 35 - 111.9 0.7

9 1.5 36 - 162.5 0.7

10.5 1.5 38 - 220.3 0.9

12 1.5 38 - 220.4 1.1

13.5 1.5 38 - 220.5 1.0

15 1.5 38 - 220.6 1.0

16.5 1.5 38 - 220.6 1.0

18 1.5 38 - 220.6 1.0

19.5 1.5 38 - 220.7 1.0

21 1.5 38 - 220.7 1.0

22.5 1.5 38 - 220.7 1.0

24 1.5 38 - 220.8 1.0




2.6 Conclusion and Recommendation

o The proposed building site over Sarankot is on top residual soil deposits followed by phyllitic

rock with quartzite, Seti formation of Lesser Himalaya.

o Rock is slightly to highly weathered in nature, fall on weak stage.

Recommendation

o A recommended allowable bearing capacity of 2.0 m wide square, shallow (OPEN) foundation

near or at particular borehole 2.0 m depth is nearly equal to 156 KN/m2. The recommended

ABC is in safer side, which is within a settlement of 40mm. It takes care of differential

settlement as well.

o A recommended allowable bearing capacity of 15.0 m wide square, shallow (OPEN)

foundation near or at or at particular borehole at 2.0 m depth is nearly equal to 156 KN/m2.

The recommended ABC is in safer side, which is within a settlement of 75 mm. It takes care

of differential settlement as well.

o Refer Pages 31, 32 and 33 for more Details (Theoretical and recommended values)

o Considering size of armored and layered soil, compaction level of material and geotechnical

empirical calculation, recommended angle of friction of soil is 34

o For 15 m wide square raft foundation, at 2.0 m below existing ground, Modulus of Sub-grade

reaction is 20,000 KN/m3, which changes significantly with depth and size of raft

foundation, so recommend to use with proper attention and calculation, based on actual size

and shape of footing.

o As described in the heading LIQUEFACTION in this report, sooner or later a very strong

earthquake is expected to occur in Nepal. Therefore the Foundation Engineer must pay due

attention in this regard.

o Because of presence of seepage water and probable rise in water table in summer, side fall

(collapse) is eminent. So, at the time of construction of foundation, it is strongly

recommended to design the appropriate temporary site protection measures based on the soil

properties shown in this report.

o The foundation Design Engineer needs not strictly follow the depth and dimension of

foundation selected in the bearing capacity analysis of this report. Designer is free to select

any other foundation dimension and depth depending upon the load of the structure. Allowable

bearing capacity depends on many variables such as adopted allowable settlement, type of

foundation, size and depth of foundation, importance of structure, cost of the project,




topographical, hydrological characteristics of river etc. Therefore once the size and depth of

the foundation is finalized the calculation may need to be refined during design phase based

on the parameters obtained from this investigation.

Important Notes;

o The recommendations and discussions presented in this report are based on the sub-surface

conditions encountered during the site work at the time of investigation and on the result of

the field and laboratory testing on samples obtained from limited number of boreholes. There

may be, however, conditions pertaining to the site which have not been into account due to the

limited number of boreholes.

o The ground water levels indicated on the logs of borings represents the measured levels at the

time of investigations and immediately 24 hour after completion of drilling works, which may

be permanent water table or seepage water from nearby small pouch of fractured/weathered

strata.

o It should be noted; however, that ground water levels are subject to variation caused by flood

and weather seasonal variations and by changes of local drainage and or pumping conditions,

and may at the times be significantly different to those measured during the investigation.

o PGA value used on this analysis report is based on a map prepared by Department of mines

and Geology, Nepal, which was only preliminary indication, due to lack of sufficient data,

which cannot forestall some diverse situation if large earthquake occur in nearby area.

o Conventional excavation equipment such as excavators, loaders and bulldozers will be

sufficient for most of the excavation work. Every effort should be done to avoid soil

disturbance at foundation level.

o Where space permits, the sides of the excavations shall be battered to a slope of two vertical

and one horizontal (2V: 1H) to avoid collapse. If these recommended side sloped cannot be

achieved for insufficient lateral space or for any other reason, lateral support system (shoring

system) for the sides of the excavation will be required and should be considered to maintain

safe working conditions.

o It is expected that the excavation work for shallow foundation (Raft) and Pile cap will be

below the water table in most of the bridge, so dewatering is required. Experience has shown

that small close-boarded excavation can be conveniently dealt with by conventional sump

pumping techniques. However, if larger excavations are to stand open for considerable period,

the installation of dewatering system may be required.

o Specialist contractors should be consulted in this regard during construction. Care should be




taken during dewatering to ensure that fines are not removed during pumping since this could

result in unpredictable settlements of the surrounding ground and associates structures.

o It is recommended that proper and efficient surface drainage be provided at the location of the

structures both during and after construction. Surface water should be directed away from the

edges of the excavation.

o The SANDY/GRAVELLY materials will probably be satisfactory for backfilling purposes,

whereas, the CLAYEY materials will not be satisfactory for backfilling purposes. However,

the final decision shall be taken during construction after complete excavation.

o The materials to be used for backfilling purposes shall be of selected fill composed of sand

and/or granular mixture free from organic matter or other deleterious substances. The

plasticity index of the backfill material shall not exceed 10 percent. It shall be spread in lifts

not exceeding 25cm in un-compacted thickness, moisture conditioned to its optimum moisture

content, and compacted to a dry density not less than 95% of the maximum dry density as

obtained by modified proctor test (ASTM D-1557).

o With prior approval from project directorate specific geotechnical designs are allowed to

adjust as per actual soil observed during construction works on specific.




2.7 References and Standards

1. Seismic Hazard Map of Nepal -2002, Department of Mines and Geology

2. AASTHO LRFD BRIDGE DESIGN SPECIFICATIONs, 4th edition

3. Canadian FOUNDATION ENGINEERING MANNUAL 4th EDITION, Canadian

Geotechnical Society 2006

4. Design Guide AGMU Memo 10.1 - Liquefaction Analysis

5. IS 2131: 1981 Method for standard penetration test for soils (first revision) 1981 Soil and

foundation engineering

6. IS 2720: Part 2: 1973 Methods of test for soils: Part 2 determination of water content (Second

revision) 1973 Soil and foundation engineering

7. IS 2720: Part 4: 1985 Methods of Test for Soils Part I: Grain Size Analysis (Second revision)

1985 Soil and foundation engineering

8. IS 2720: Part 3: Sec 1: 1980 Methods of test for soils: Part 3 Determination of specific gravity

Section fine grained soils (First revision) 1980 Soil and foundation engineering

9. IS 2720: Part 10: 1991 Methods of test for soils: Part 10 Determination of unconfined

compressive strength (Second revision) 1991 Soil and foundation engineering

10. Is 2720: Part 13: 1986 Methods of Test for Soils - Part 13: Direct shear Test (Second revision)

1986 Soil and foundation engineering

11. IS 6403: 1981 Code of practice for determination of bearing capacity of shallow foundations

12. IS 8009: Part 1: 1976 Code of Practice for Calculation of Settlements of Foundations - Part I:

Shallow Foundations Subjected to Symmetrical Static Vertical Loads 1976 Soil and foundation

engineering

13. IS 8009: Part I: 1976 Code of Practice for Calculation of Settlements of Foundations - Part I:

Shallow Foundations Subjected to Symmetrical Static Vertical Loads

14. IS 8009: Part II: 1980 Code of Practice for Calculation of Settlement of Foundations - Part II:

Deep Foundations Subjected to Symmetrical Static Vertical Loading

15. IS 2911: Part 1: Sec 2: 1979 Code of practice for design and construction of pile foundations:

Part 1 Concrete piles, Section 2 Bored cast-in-situ piles

16. IS 2950: Part I: 1981 Code of Practice for Design and Construction of Raft Foundations - Part

I: Design

SOIL INVESTIGATION REPORT

OF FLIP NEPAL RESORT PTE LTD

SARANKOT, KASKI, NEPAL

September, 2014

Prepared BY:

MATERIAL TEST (P) LTD Web: material-test.com.org

E-Mail: [email protected] Phone/Fax: 01-4486092

Mid Baneswor, Kathmandu, Nepal




Annex Borehole log

Laboratory Test Results




Borehole log and Laboratory Test Data

Project : Soil Investigation of Proposed Building Foundation Hole No.: D - 1

Client : FLIK NEPAL RESORT PET LTD Date: 22/08/2014 ~ 25/08/2014

Location : SARANKOT, Kaski, Nepal Ground water table: GL- Not Encountered

Method of Drilling: Rotary Hole Dia.: HX, NX, BX

N-Value SPT

UDS DCPT

- 1 SPT 7 9 11 20

- 2 SPT 12 14 13 27

- 3 SPT 17 19 23 42

- 4 SPT 50/12 > 50

- 5 SPT 50/10 > 50

- 6

- 7

- 8

- 9

- 10

- 11

- 12

- 13

- 14

- 15

End Depth * Completed at 15m

Types of Soil

16 to 32 > 32

Very Soft Soft Med. Soft Stiff Very Stiff Hard

8 to 16Cohesive Soil Consistency

0 to 2 2 to 4 4 to 8

Brownish grey dense sandy silt with

small gravel of weathered phyllite

N Value

Radish brown to yellowish white

highly weathered phyllitic rock

(WEAK BED ROCK)

Granular Soil Compactness0 to 4 4 to 10 10 to 30 > 50

Very Loose Loose Med. Dense Dense Very Dense

30 to 50

Borehole Log

Soil Description

Sy

mb

ol

Dep

th,

m

Sam

ple

No

.

&T

yp

e

No. of blows

N-V

alu

e

15

cm

15

cm

15

cm

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

0 10 20 30 40 50





N-Value SPT

UDS DCPT

- 1 SPT 15 17 16 33

- 2 SPT 13 14 16 30

- 3 SPT 50/14 > 50

- 4 SPT 50/13 > 50

- 5 SPT 50/11 > 50

- 6 SPT 50/10 > 50

- 7

- 8

- 9

- 10

- 11

- 12

- 13

- 14

- 15


Types of Soil

16 to 32 > 32

Very Soft Soft Med. Soft Stiff Very Stiff Hard

8 to 16Cohesive Soil Consistency

0 to 2 2 to 4 4 to 8

Light grey to brownish medium

dense to dense sandy gravel with

fresh to weathered fragments of

phyllite with quartzite

N Value

Light grey to brownish fresh to

slightly weathered phyllitic rock

with quartzite (WEAK BED

ROCK)

Granular Soil Compactness0 to 4 4 to 10 10 to 30 > 50

Very Loose Loose Med. Dense Dense Very Dense

30 to 50

Borehole Log

Soil Description

Sy

mb

ol

Dep

th,

m

Sam

ple

No

.

&T

yp

e

No. of blows

N-V

alu

e

15

cm

15

cm

15

cm

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

0 10 20 30 40 50





N-Value SPT

UDS DCPT

- 1 SPT 12 10 9 19

- 2 SPT 14 16 16 32

- 3 SPT 14 15 16 31

- 4 SPT 17 19 20 39

- 5 SPT 50/13 > 50

- 6

- 7

- 8

- 9

- 10

- 11

- 12

- 13

- 14

- 15


Types of Soil

8 to 16 16 to 32 > 32

Very Soft Soft Med. Soft Stiff Very Stiff HardCohesive Soil Consistency

0 to 2 2 to 4 4 to 8

N Value

Granular Soil Compactness0 t

flip nepal final report

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