activities of the geotechnical research group on ... · 1 geotecnia universidade de brasília...

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GEOTECNIA Universidade de BrasíliaUniversidade de Brasília

Activities of the Geotechnical Research

Group on Foundations (GPFees)

University of Brasília-Brazil

Renato P. Cunha

Civil Engineer, Ph.D., Associate Professor

University of Brasília, Dept. of Civil & Env. Engineering

Geotechnical Graduation Program

University of Applied Sciences

Munich, May 2015

Special Lecture


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City and University Characteristics

Research Lines of the GPFees Group

On Going MSc & DSc Students

Recent Research Details

LAYOUT


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Central Region of Brazil

3 states + Federal Dist.

1,606,371 km²

19% Brz total area

(4.5 x Germany)

13,270,000 inhabitants

7% Brz total inhab.

Avg 8.3 inhab/km2

8.8% GNP

(3.7% for Fed. District)


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Federal District

BRASIL N

a

Area = 5822 km2

Population = 2.6 millions inhabitants

Density 443 inhab/km2

~50 km

~30 km


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Brazil x Germany

Area Brazil 24 x Area Germany

Population Brazil 2.5 x Pop. Germany

(approximate relative dimensions)

Data from: Main Indicators. Central Bureau of

Statistics homepage (2015). Wikipedia

http://upload.wikimedia.org/wikipedia/commons/4/48/Brazil_State_DistritoFederal.svg

http://www1.cbs.gov.il/reader/cw_usr_view_Folder?ID=141




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Brasília City


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University of Brasília

30000 undergrad students, 5000 grad

2000 professors

Photo


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Geotechnical Graduation Program

www.geotecnia.unb.br

Statistics

12 Professors, 51 MSc

students, 57 DSc students

•MSc Program since 1989 and

DSc since 1996

•Defended +80 DSc Theses

and +200 MSc Theses

•Entrance: 16 MSc and 8 DSc

per year

• Scholarships: 37 MSc-31 DSc


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Personal Homepage



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Research Lines

Foundations and In Situ Testing

• Site behavior of real scale isolated foundations as well as groups and

piled rafts;

• Design and simulation of deep foundations via in situ and laboratory

tests coupled with numerical or analytical techniques;

• Simulation of standard pile groups and piled raft foundations under

small scale model conditions (1g and centrifuged);

• Use of site investigation techniques to obtain geotechnical

parameters in tropical soils, to enhance geo-environmental designs;

• Instrumentation of foundation systems at real or small scale sizes;

• Influence of defective piles and the reinforcement system in the

behavior of foundation groups and piled rafts;

• Soil-superstructure interaction;

• Special foundations for dynamic wind power generators;

• Energy foundations for heat transfer with the geotechnical medium.


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Research Lines

Soil Stabilization via Retaining Structures

• Site behavior and design of real scale retaining structures;

• Use of field and laboratory tests to design and simulate retaining

structures founded on tropical soil;

• Assessment of numerical and analytical techniques to forecast the

behavior of retaining structures;

• Instrumentation of retaining structures in terms of loads, pressures

and displacements during and after construction;

• Influence of external and internal factors as weather seasonality,

geotechnical parameters, suction etc. on the behavior of such

structures;

• Study of soil nailing and active anchors.


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On Going Research Work

6 DSc

3 MSc

1 Final

Project


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Brief Results of Recent Research

DSc Students

Juan Carlos

Osvaldo

Christian

Dasiel

Edgar

Francisco

Figueiredo

Raydel

MSc Students

Henry

Gabriela


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Juan Carlos Ruge Cardenas

Colombian Student

Analysis of the Behavior of Pile Curtain

walls executed in porous and

metastable soil through the use of a

hypoplastic constitutive model that

considers the unsaturated soil

response

DSc Thesis

192 pages

Defended May 2014

Defended DSc Thesis


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Calibration of parameters hypoplastic model

Ruge 2009/2014

FEM simulations

Computational model 17


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Defended DSc Thesis

Osvaldo de Freitas Neto

Brazilian Student

Experimental and Numerical Evaluation of

Piled Raft with Defective Piles in Brazil's

Tropical Soil

DSc Thesis

253 pages

Defended August 2013


Instrumentação da Ponta da Estaca

ESQUEMA LONGITUDINAL DAS ESTACAS DEFEITUOSAS (E9, E13 e E26)

Instrumentação doTopo de Estaca

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0

20

40

60

80

100

120

0 100 200 300 400 500 600 700 800 900 1000 1100 1200

Rec

alq

ue

(mm

)

Carga (kN)

CF1(NUM) R1INT (NUM) Ruptura Estrutural / GeotécnicaCF1 (EXP)

0

10

20

30

40

50

60

70

80

90

100

0 15 30 45 60 75 90 105 120 135 150

Carg

a p

or

Ele

men

to (

kN

)

Carga Total Aplicada (kN)

E13 (Defeituosa) Carga no Radier Ruptura Estrutural / Geotécnica

0,14 0,19 0,32 0,72 2,01 3,11 100,269,56,54

Recalque (mm)

% Carga na Estaca % Carga no Radier Ruptura Estrutural / Geotécnica

Fs = 1

0,0

2,0

4,0

6,0

8,0

10,0

15 30 45 60 75 90 105 120 125 131 135

Fa

tor

de

Seg

ura

nça


Fs Global CF1 - EXPERIMENTAL

Fs Global (R1INT) - NUMÉRICO0 100 200 300 400 500 600 700

Dis

torç

ão

An

gu

lar


CF1 CF3 CF4

1/100

1/50

1/20

1/25

1/16,6

1/14,3

1/12,5

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Defended DSc Thesis

Cristhian Camilo Mendoza Bolaños

Colombian Student

The mechanical behavior of pile

groups and piled rafts with

Alluvial Anker piles types installed

in porous clays of the Federal

District of Brazil.

DSc Thesis

234 pages

Defended September 2013


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Calibration of constitutive models

Experimental data x Numerical Parametric

Results

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On Going DSc Thesis

Dasiel Hernández Fernández

Cuban Student

Determination of laterally

loaded foundations numerical

analyses of pressuremeter tests

and computer modeling

techniques

DSc Thesis

Defense in 2017


Correlations

Menard Pressuremeter

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Displacement Stress

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Edgar Rodríguez Rincón

Colombian Student

Experimental analysis of the

behavior of piled raft systems

in soft soil with consolidation

processes

DSc Thesis.

Defense in 2016

On Going DSc Thesis


Influence of

drawndown

Centrifuge tests in small scale models

Distinct model types 28


Load test of pile in 1/70 model.

Load test of plate in 1/70 model.

Water pressure, displacement and

load results

Modelling box and piled raft model

4x4 to 1/200 model test.

Settlement of soil, raft (up) and

piled raft (down), in 1/200

model. 29


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Francisco Javier Alva García

Mexican Student

Analysis of the Behavior of Piled

Rafts with and without defective

piles, laterally loaded into a

tropical laterized soil of Brazil

DSc Thesis

Defense in 2017

On Going DSc Thesis


Piled Raft under laterally loaded

Damaged piles

Area

reduction

Low

resistance

zone

Fissuration

zone Top pile

damage

Defective piles examples

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Abaqus software (MEF) for modelling

Single pile Single pile results under lateral loading

soil Raft

and

piles

Assambly

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Luiz Carlos de Figueiredo

Brazilian Student

Energy Measurement of Dynamic

Light Probe Tests (DPL) on Porous

Tropical Soil

Defense in 2016

190 pages

On Going DSc Thesis


Details of accelerometers

Test setup with DPL

Preparation

of laboratory

DPL

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Acquired and integrated signal

0 4 8 12 16 20 24

0

5

10

15

20

25

30

35

40

45

50

Inte

gra

ted

en

erg

y (

Jo

ule

s)

Tempo (ms)

Integrated energy

Permanent penetration

Theoretical energy= 49,03 Joules

20

18

16

14

12

10

8

6

4

2

0

Pe

rma

ne

nt p

en

etr

atio

n (

mm

)

Energy evolution for penetration of 18 mm

0 4 8 12 16 20 24 28 32

20

25

30

35

40

45

50

55

EFV

EF

V (

Jo

ule

s)

(mm)

Equation y = 14,55 +2,30*x - 0,037*x^2

R²= 0,93744

EFV versus permanent penetration

Theoretical energy =49,03 Joules

EFV - maximum energy transferred to the rods

0 5 10 15 20 25 30 35 40 45 50 55

40

50

60

70

80

90

100

nD

PL

(%

)

Blows per 0.1 meter, N10

nDPL

Efficiency of energy for DPL (nDPL)

Energy efficiency per blow

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Raydel Lorenzo Reinaldo

Cuban Student

Analysis of Displacement Piles

Using the Material Point Method

Defense in 2015

On Going DSc Thesis


Large strain and distortion problems Simulation of Pile Installation

Idealized

exponential

curve

Typical in-situ

profile

k0

Skin friction

Pile

penetr

ation

Porosity:

Density:

Resistance: 37

Battuto.exe

trivellato2.exe


1. Modified Cam Clay

2. Subloading Cam Clay f = M 2(p2 - p0 p)+ q2

Analytical vs. Numerical

Exp. vs. Numerical

Implementation and Validation of

Constitutive Models for Soils

Professor John A. Nairn

NairnMPM Code: Material Point Method

code for Mechanics Analysis

Jardine et al. (2013)

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Henry Castillo Orozco

Colombian Student

Numerical and Parametric

Study of Energy Piles Founded

in Tropical Soil

Defense in 2016

On Going MSc Thesis

Mathieu Velle – BSc Level

Exchange French Student


Energy pile-soil thermal interaction

System Layout – Primary and Secondary

Example of Instalation (U Pipes)

(Brandl, 2010) 40


Modeling in a Finite Element Model (MEF) Expected Results

(Gashti, 2014)

(Bidarmaghz A., 2013)

Considerations

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Gabriela de Athayde Duboc Bahia

Brazilian Student

Evaluation of the Behavior of Deep

Foundation Groups in normal

Edifications in the Federal District

of Brazil with the Use of Soil-

Interaction Techniques

Defense in 2016

On Going MSc Thesis


Soil Profile

NSPT

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Parametric Analyses

Field Displacements

P209 P212 P218 P223 P225 P226 P233 P234 P235 P237 P238

P209 - 1/7137 1/8910 1/5093 0 0 0 0 0 1/8854 1/5563

P212 -1/

7137 - 0 0 0 -1/8931 0 0 0 0 1/9630

P218 -1/

8910 0 - 0 0 -1/3753 0 0 0 1/8859 1/5281

P223 -1/

5093 0 0 - 0 -1/4559 0 -1/7130 0 0 1/8519

P225 0 0 0 0 - 0 0 0 0 1/2946 1/4249

P226 0 1/8931 1/3753 1/4559 0 - 0 1/7822 0 1/4921 1/1564

P233 0 0 0 0 0 0 - 0 1/4980 1/3209 1/9056

P234 0 0 0 1/7130 0 -1/7822 0 - 0 1/8624 1/3163

P235 0 0 0 0 0 0 -1/

4980 0 - 0 0

P237 -1/8854 0 -1/8859 0 -1/2946 -1/4921 -1/3209 -1/8624 0 - 0

P238 -1/5563 -1/9630 -1/5281 -1/

8519 -1/4249

-1/ 1564

-1/9056 -1/3163 0 0 -

Differential Displacements

Interaction Factors for Typical Pile Diameter

Real Case

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Large Effort to form Researchers and to

Gather Knowledge

Collaborative Work is welcome!

Scholarships are available

Summary


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THANK YOU

Vielen Danke

You can´t image how much

of Brazil are there inside us!

activities of the geotechnical research group on ... · 1 geotecnia universidade de brasília...

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