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International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 10, October 2017, pp. 1170–1180, Article ID: IJCIET_08_10_120
Available online at http://http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=8&IType=10
ISSN Print: 0976-6308 and ISSN Online: 0976-6316
© IAEME Publication Scopus Indexed
STRUCTURAL EVALUATION OF DAMAGED
BRI BRANCH OFFICE BUILDING AT JALAN
KHATIB SULAIMAN PADANG DUE TO
EARTHQUAKE
Zaidir
Civil Engineering Department
Faculty of Engineering, University of Andalas, Padang, Indonesia
Fauzan
Civil Engineering Department
Faculty of Engineering, University of Andalas, Padang, Indonesia
Abdul Hakam
Civil Engineering Department
Faculty of Engineering, University of Andalas, Padang, Indonesia
Febrin Anas Ismail
Civil Engineering Department
Faculty of Engineering, University of Andalas, Padang, Indonesia
ABSTRACT
The earthquake 30 September 2009 in West Sumatera has caused damage to many
buildings in Padang City, Indonesia. One of building that also suffered severe damage
is BRI branch office which is located at Jalan Khatib Sulaiman Padang. This paper
discussed the structural evaluation of damaged BRI branch office building whether it
can be used again or not. Evaluation was done on non-structural and structural
elements of the building. The structural analysis was used ETABS program ver. 9.7.1
with properties of material is taken from the test results of existing structures. The
standard code is used is Earthquake Resilience Planning Standard for Building
Structure 2002 (SNI 03 - 1726 - 2002) and the Hazard map Indonesia earthquake in
2010 with location of Padang city. From the results of the evaluation it was found that
the building is not structurally feasible and recommended not to be use or to be
destroyed
Keywords: Earthquake 30 September 2009, structural evaluation, non-structural and
structural elements
Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail
http://www.iaeme.com/IJCIET/index.asp 1171 [email protected]
Cite this Article: Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail, Structural
Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang
Due to Earthquake, International Journal of Civil Engineering and Technology, 8(10),
2017, pp. 1170–1180
http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=8&IType=10
1. INTRODUCTION
The BRI branch office building located on Jalan Khatib Sulaiman Padang is one building that
suffered severe damage due to tectonic earthquake of 7.9 SR which occurred on September
30, 2009 in West Sumatera. The earthquake has resulted various damages both facilities and
physical infrastructure and casualties on various area in West Sumatera Province. Based on
data published by Satkorlak PB West Sumatra and BNPB were known the facilities and
infrastructure sector loss reached Rp. 963 billion. The education sector also suffered damage
due to the earthquake. A total of 1,384 school buildings were heavily damaged, 1,018 were
moderately damaged and 744 were slightly damaged with damage value of Rp.588,7 billion
(Fauzan, 2012).
The structural evaluation of the BRI branch office is intended to conduct the structural
evaluation of the building, is it still feasible to be used or not. The evaluation was conducted
on the existing building condition and the necessary data for structural analysis is taking
directly. The dimension of structural elements buildings such as columns, beams and plates
are obtained from as built drawings and a concrete quality using a hammer test. The structural
analysis using computer simulation of ETABS program ver. 9.7.1. A building code used the
Earthquake Resilience Planning Standard for Structures Building 2002 (SNI 03 - 1726 - 2002)
and The Hazard map of Indonesia earthquake in 2010 with the location of Padang city, West
Sumatera. The bearing capacity of the foundation was evaluated using the data of DCP (Ducth
Cone Penetrometer)
2. BUILDING GENERAL DATA
2.1. Building Data
The three floors of BRI branch office building is a rectangular RC frame with size of 19,20 m
x 24,00 m. Figure 1 and 2 show the lay-out of building and the beam column position of
second, third and roof floors. Table 1 shows a column and beam dimensions of building.
Figure 1 Building lay-out and column-
beam position at 2nd
and 3rd
floor
Figure 2 Building lay-out and column-
beam position at roof floor
Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due
to Earthquake
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Tabel 1 Column and beam dimensions of building
Floor Column dimension
(in mm)
Beam dimension
(in mm)
1
400 x 400
250 x 400
350 x 650
350 x 450
300 x 300 250 x 400
350 x 650
2
400 x 400
250 x 450
350 x 650
350 x 450
300 x 300 250 x 450
350 x 650
3 400 x 400
250 x 450
250 x 500
300 x 600
300 x 300 300 x 600
2.2. Code and Standards
The code and standards for a loading and a structural evaluation which was used are below :
• SNI 03-1726-2002: Earthquake Resilience Planning Standard for Building Structure
• SNI 03-2847-2002: Standard of Design of Reinforced Concrete and Buildings
Structures
• SNI 03-1729-2002: Standard of Design Steel Structure for Building Structures
• SNI 03-1727-1989: Standard of Loading Design for Housing and Buildings.
• ACI 318-08-2008: Building Code Requirements for Structural Concrete and
Commentary
• Hazard Map of the Indonesia Earthquake 2010 as the Basic of Planning and Design of
Earthquake Resistant Infrastructures.
2.3. Material Quality
The structural concrete quality data is obtained directly by a concrete hammer test. The
concrete quality which is obtained from the hammer test is quite good. For beams and plates,
the average concrete quality is fc’ = 22,5 MPa and a columns is fc' = 30 MPa. The steel
reinforcement quality is used are BJTP-24 (fy = 240 MPa) for plain bar and BJTD-39 (fy = 390
MPa) for deformed bar respectively.
3. DAMAGE EVALUATION OF EXISTING BUILDING
Based on a direct field observation, the damage of building can be categorized to non-
structural and structural elements. Damages of non-structural element are a damage that
occurs in the non-structural parts of buildings such as brick walls, ceilings, floor covering etc.
The structural damages are a cracked or broken of structural elements building, such as
columns, beams, plates and foundation.
Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail
http://www.iaeme.com/IJCIET/index.asp 1173 [email protected]
3.1. Non-structural Damages
The most dominant non-structural damages were found at first floor of building. The damages
are found in the form of cracks and collapse of the brick walls, ceiling and ceramic removal
on the floor building.
Damages of the brick wall occur almost in all parts of the wall building on the first floor.
Damage occurs in the form of a large crack until the collapse of some parts of the wall. Some
typical damage of brick walls that occurs in building can be seen in Figure 3. At the 2nd and
3rd floors the non-structural damage that occurs on the walls is only a fine crack up to
medium crack at some parts of the wall.
Figure 3 Typical non-structural damage of brick wall at the first floor of building.
Damage of the ceiling occurs in several places. Damage occurs in the form of frame
ceiling damage that resulted ceiling detached. At some point of the floor, damage occurred in
the form of ceramic floor covering removal. The damage occurs due to the movement of
structural elements such as beams and columns at the time of the earthquake. Figure 4 shows
the damage of ceiling where the damage of floor covering is shown in Figure 5.
Figure 4 Damage of ceiling Figure 5 Damage of floor covering
3.2. Structural Damage
Structural damage are the damages that occurs in columns, beams, plates and stairs related to
the strength of the building structure. Dominantly the structural damages occur on the first
floor of the building.
Damages of column structure are in the form of concrete failure and shear reinforcement
release on the top column. Some location and forms of the damage of columns are shown in
Figure 6. The main stair connecting the first to second floor was severely damaged as shown
Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due
to Earthquake
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in Figure 7. This is due to the different structural behavior of stair with the behavior of overall
building structure
Figure 6 Column damage and released of
shear reinforcement Figure 7 Damage of stair structure
4. EVALUATION OF CAUSES OF BUILDING DAMAGES
Evaluation of the non-structural and structural damage occurs in the building it can be
concluded that the building suffered severe damage, especially on the 1st floor of the building.
From direct field observation it can be identified possible cause of damage to buildings as
follows:
a. The beam-column joint is not monolith. This condition could be seen at all the
damaged 1st floor columns. Visually it can seen that the concrete on the 1
st floor
column was damage in the area beam-column joint, but the concrete on the beam is
not damaged.
b. The hook of the shear reinforcement does not meet the standards. At damaged column
it appears that the shear reinforcement split apart. This occurs due to hooks of stirrups
do not meet standards
c. Strong column weak beam mechanism is not implemented
From the field observation and verification of as built drawing it is obtained data that the
size a column is smaller than the size of a beam. This is tends the concrete damage occurs in
the part of column only.
5. STRUCTURAL ANALYSIS
5.1. Structural Modeling and Loading
Structural modeling is done in 3-dimensional form. Technical specifications structure for
structural analysis is as follows:
• Building location : Jl. Khatib Sulaiman Padang
• Earthquake Region : Padang city : Padang
• Soil type: Soft soil
Concrete quality
Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail
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Column: K - 300 kg / cm2
Beam: K - 225 kg / cm2
Plates: K - 225 kg / cm2
• Reinforced Steel quality:
BJTP-24 (fy = 240 MPa) for plain bar
BJTD-39 (fy = 390 MPa) for deformed bar
Figure 8 shows the structure modeling in 3-dimensional form. Design of loading of dead
load (DL) and live load (LL) based on SNI 03-1727-1989 Standard of Loading Design for
Housing and Buildings. The design of earthquake load using the Hazard Map of the Indonesia
Earthquake 2010 as shown in Figure 9. Structural analysis using ETABS program version
9.7.1.
The combination of loading taken is as follows:
1. U = 1,4 DL
2. U = 1,2 DL + 1,6 LL
3. U = 1.2 DL + 1,0 LL + 1,0 DNX1 + 0,3 DNY1
4. U = 1,2 DL + 1,0 LL + 1,0 DNX1 – 0,3 DNY2
5. U = 1.2 DL + 1,0 LL – 1,0 DNX2 + 0.3 DNY1
6. U = 1,2 DL + 1,0 LL – 1,0 DNX2 – 0,3 DNY2
7. U = 1,2 DL + 1,0 LL + 0,3 DNX1 + 1,0 DNY1
8. U = 1.2 DL + 1,0 LL + 0,3 DNX1 – 1,0 DNY2
9. U = 1,2 DL + 1,0 LL – 0,3 DNX2 + 1,0 DNY1
10. U = 1,2 DL + 1,0 LL – 0,3 DNX2 – 1,0 DNY2
Where:
DL = dead load
LL = live load
DNX1 = earthquake load from right
DNX2 = earthquake load from left
DNY1 = earthquake load from front
DNY2 = earthquake load from behind
Figure 8 Building structural modeling Figure 9 Design of earthquake load for
Padang city
Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due
to Earthquake
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5.2. Capacity Analysis of Column Section
Figure 10 and Figure 11 show the interaction diagram curves of axial force and bending
moment (P-M) and plotting axial forces and bending moments obtained from structural
analysis for column K1 at the first and second floors. From Figure 10 and 11 it can be seen
that for the axial force (P) the column capacity is greater than the axial load, but for bending
forces the column capacity is less than the bending load. This is evident from the presence of
a number of bending loads located outside the interaction diagram curves, either on the first or
second floor.
Figure 10 Column interaction diagram of K1 at
1st floor
Figure 11 Column interaction diagram of K1
at 2nd
floor
Tables 2 show the bending and shear capacity of all columns for every building floors.
From the table it can be seen that the bending capacity of the columns on the first and second
floors is insufficient, while for shear capacity is still sufficient.
Table 2 Bending and shear capacity of all columns
Column Dimension
(mm)
Bending
capacity
Shear capacity
installed Necessary remarks
1
K1 400x400 not Ok 165,66 kN 120,30 kN Ok
K2 400x400 not Ok 165,66 kN 121,74 kN Ok
K3 400x400 not Ok 165,66 kN 125,31 kN Ok
K4 400x400 not Ok 165, 66 kN 130,63 kN Ok
K5 400x400 not Ok 165.66 kN 107,01 kN Ok
K6 300x300 not Ok 165,66 kN 51,73 kN Ok
2
K1 400x400 not Ok 165,66 kN 83,23 kN Ok
K2 400x400 not Ok 165,66 kN 92,27 kN Ok
K3 400x400 not Ok 165,66 kN 93,06 kN Ok
K4 400x400 not Ok 165,66 kN 94,52 kN Ok
K5 400x400 not Ok 165,66 kN 73,50 kN Ok
K6 300x300 not Ok 102,88 kN 42,68 kN Ok
3
K1 400x400 Ok 165,66 kN 42,72 kN Ok
K3 400x400 Ok 165,66 kN 45,57 kN Ok
K4 400x400 Ok 165,66 kN 54,09 kN Ok
Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail
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K5 400x400 Ok 165,66 kN 36,27 kN Ok
K6 300x300 Ok 102,88 kN 21,65 kN Ok
5.3. Capacity Analysis of Beam Section
The actual bending and shear capacity of beam are summarized in Table 3. It can be seen that
some of bending and shear capacity of beam section is insufficient.
Table 3 Bending and shear capacity of beam
No. Beam Reinforcement
position
Max.
capacity
Internal
forces Remarks
��Mn- /
��Vn Mu - / Vu
1 (250/450)
L = 4,800 mm
Ben
din
g Top support 168.30 kNm 162.58 kNm Ok
Bottom support 87.34 kNm 117.29 kNm Not Ok
Top centre 87.34 kNm 116.56 kNm Not Ok
Bottom centre 168.30 kNm 152.69 kNm Ok
Sh
ear
Support 169.49 kN 117.23 kN Ok
Centre 131.79 kN 99.15 kN Ok
2 (350/650)
L = 7,200 mm
Ben
din
g Top support 330.80 kNm 453.48 kNm Not Ok
Bottom support 201.74 kNm 274.91 kNm Not Ok
Top centre 330.80 kNm 268.22 kNm Ok
Bottom centre 201.74 kNm 128.39 kNm Ok
Sh
ear
Support 288.08 kN 274.67 kN Ok
Centre 231.53 kN 233.17 kN Not Ok
5.4. Bearing Capacity Analysis of Foundation
The bearing capacity of building foundation is determined by comparing the permit bearing
capacity of existing foundation to a total working load, with and without earthquake for every
building column. The bearing capacity of the foundation (Qa) is calculated by the Meyerh of
formula (1956) using DCP (Dutch Cone Penetrometer) test results as follows :
�� = 0,025. � . � ; � �� ��� (1)
� = 14� . �. �� ; �� �� (2)
Where:
qc = value of DCP test (= 15,000 kPa.
Ap = area of foundation cross section
D = diameter of foundation (= 1,50 m)
Table 4 shows the axial load on each foundation point, with and without earthquake
compared to bearing capacity of foundation. From Table 4 it can be seen that the bearing
capacity of existing foundation is insufficient to support the design load.
Structural Evaluation of Damaged Bri Branch Office Building At Jalan Khatib Sulaiman Padang Due
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Table 4 Bearing capacity of foundation with and without earthquake load
Point
Axial load of column Total
without
earthquake
Total
with
earthquake
Allowable
bearing
capacity
Remarks
DL LL Eqx Eqy without
earthquake
with
earthquake (tonf) (tonf) (tonf) (tonf) (tonf) (tonf) (tonf)
1 66.49 8.37 2.54 23.96 74.87 98.82 66.27 Not Ok Not Ok
2 64.30 8.55 1.10 24.96 72.86 97.81 66.27 Not Ok Not Ok
3 82.67 14.75 3.18 16.63 97.41 114.05 66.27 Not Ok Not Ok
4 71.61 10.07 24.95 17.37 81.67 106.62 66.27 Not Ok Not Ok
5 53.73 17.88 2.69 6.43 71.62 84.37 66.27 Not Ok Not Ok
6 57.50 15.53 2.36 6.64 73.02 85.74 66.27 Not Ok Not Ok
9 63.27 19.33 2.90 1.54 82.59 95.38 66.27 Not Ok Not Ok
10 59.56 16.83 2.99 1.77 76.39 89.24 66.27 Not Ok Not Ok
11 51.33 8.07 4,53 21.35 59.40 80.75 66.27 Ok Not Ok
12 40.91 7.99 4,98 22.27 48.89 71.17 66.27 Ok Not Ok
13 83.65 12.32 25.38 17.15 95.97 121.34 66.27 Not Ok Not Ok
14 96.55 14.67 3.91 15.59 111.22 126.80 66.27 Not Ok Not Ok
15 69,28 6.70 2.52 37.90 75.98 113.88 66.27 Not Ok Not Ok
16 58.31 6.73 1.67 39.04 65.04 104.07 66.27 Ok Not Ok
17 73.98 14.70 3.82 16.81 88.68 105.49 66.27 Not Ok Not Ok
18 83.99 11.57 24.61 16.98 95.56 120.17 66.27 Not Ok Not Ok
19 92.00 16.41 22.61 1.78 108.41 131.01 66.27 Not Ok Not Ok
20 91.53 16.50 22.49 2.26 108.02 130.52 66.27 Not Ok Not Ok
21 83.01 12.23 24.93 16.83 95.24 120.17 66.27 Not Ok Not Ok
22 75.19 14.78 22.13 2.03 89.97 112.10 66.27 Not Ok Not Ok
23 70.58 15.27 22.45 2.21 85.85 108.30 66.27 Not Ok Not Ok
24 84.66 14.84 4.37 15.31 99.50 114.80 66.27 Not Ok Not Ok
25 66.35 14.74 3.70 1.31 81.09 95.58 66.27 Not Ok Not Ok
26 59.45 14.48 3.12 1.55 73.93 88.38 66.27 Not Ok Not Ok
27 67.17 14.72 4.22 1.24 81.89 96.70 66.27 Not Ok Not Ok
28 48.11 14.74 4.02 1.26 62.84 77.52 66.27 Ok Not Ok
29 37.88 6.50 6.93 2.49 44.37 51.31 66.27 Ok Ok
30 37.35 6.25 6.44 3.10 43.60 50.04 66.27 Ok Ok
Max
96.55 19.33 25.38 39.04 111.22 131.01 66.27 Not Ok Not Ok
6. CONCLUSION AND RECOMMENDATION
6.1. Conclusion
From the results of the structural evaluation of BRI branch office building at Jl. Khatib
Sulaiman Padang, it can be summarized as follows :
1. Non structural damage occurs at the walls, ceilings, and removal of floor tiles at
several locations.
2. Structural damage occurs on the first floor, namely with heavily damaged conditions
on column and stair structures.
Zaidir, Fauzan, Abdul Hakam and Febrin Anas Ismail
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3. In the implementation of the work of building structures found many implementation
errors which occurs in the field, for instance the beam column joint are not monoliths,
hooks reinforcement for shear do not meet a standard.
4. The concrete quality testing with hammer test is still quite good for concrete quality
standard that is above K-225 kg / cm2.
5. The bending capacity at the first and second floor columns insufficient compared to
design bending capacity.
6. The bearing capacity of the existing foundation is not capable to support the building
axial load.
7. Based on the above points, it is concluded that the building of BRI branch office at
Khatib Sulaiman no. 50 Padang cannot more used and should be destroyed.
6.2. Recommendation
Based on the conclusion, it is recommended that the damaged BRI branch office building at
Jalan Khatib Sulaiman no. 50 Padang cannot more used and proposed to be destroyed.
ACKNOWLEDGEMENTS
The authors would like to thanks to the foundation of Dana Pensiun BRI Jakarta to perform
the structural evaluation of damaged BRI Branch Office at Jalan Khatib Sulaiman no. 50
Padang.
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