Numerical Modeling in Geoenvironmental Practice
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Finite Element Study on Static Pile Load Testing Li Yi A
FINITE ELEMENT STUDY ON STATIC PILE LOAD TESTING LI YI (B.Eng) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ENGINEERING DEPARTMENT OF CIVIL ENGINEERING NATIONAL UNIVERSITY OF SINGAPORE 2004 Dedicated to my family and friends ACKNOWLEDGEMENTS The author would like to express his sincere gratitude and appreciation to his supervisor, Associate Professor Harry Tan Siew Ann, for his continual encouragement and bountiful support that have made my postgraduate study an educational and fruitful experience. In addition, the author would also like to thank Mr. Thomas Molnit (Project Manager, LOADTEST Asia Pte. Ltd.), Mr. Tian Hai (Former NUS postgraduate, KTP Consultants Pte. Ltd.), for their assistance in providing the necessary technical and academic documents during this project. Finally, the author is grateful to all my friends and colleagues for their help and friendship. Special thanks are extended to Ms. Zhou Yun. Her spiritual support made my thesis’ journey an enjoyable one. i TABLE OF CONTENTS ACKNOWLEDGEMENTS............................................................................................. i TABLE OF CONTENTS................................................................................................ii SUMMARY................................................................................................................... iv LIST OF TABLES......................................................................................................... vi LIST OF FIGURES ......................................................................................................vii -
Isotropic Work Softening Model for Frictional
Yang, K.-H., Nogueira, C., and Zornberg, J.G. (2008). “Isotropic Work Softening Model for Frictional Geomaterials: Development Based on Lade and Kim soil Constitutive Model.” Proceedings of the XXIX Iberian Latin American Congress on Computational Methods in Engineering, CILAMCE 2008, Maceio, Brazil, November 4-7, pp. 1-17 (CD-ROM). ISOTROPIC WORK SOFTENING MODEL FOR FRICTIONAL GEOMATERIALS: DEVELOPMENT BASED ON LADE AND KIM CONSTITUTIVE SOIL MODEL Kuo-Hsin Yang [email protected] Dept. of Civil Engineering, The University of Texas at Austin, Texas, Austin, USA Christianne de Lyra Nogueira [email protected] Dept. of Mine Engineering, Universidade Federal de Ouro Preto, MG, Brazil Jorge G. Zornberg [email protected] Dept. of Civil Engineering, The University of Texas at Austin, Texas, Austin, USA Abstract: An isotropic softening model for predicting the post-peak behavior of frictional geomaterials is presented. The proposed softening model is a function of plastic work which can include all possible stress-strain combinations. The development of softening model is based on the Lade and Kim constitutive soil model but improves previous work by characterizing the size of decaying yield surface more realistically by assuming an inverse sigmoid function. Compared to original softening model using the exponential decay function, the benefits of using the inverse sigmoid function are highlighted as: (1) provide a smoother transition from hardening to softening occurring at the peak strength point, and (2) limit the decrease of yield surface at a residual yield surface, which is a minimum size of yield surface during softening. The proposed softening model requires three parameters; each parameter has it own physical meaning and can be easily calibrated by a triaxial compression test. -
Numerical Study on the Hydrologic Characteristic of Permeable Friction Course Pavement
water Article Numerical Study on the Hydrologic Characteristic of Permeable Friction Course Pavement Tan Hung Nguyen 1 and Jaehun Ahn 2,* 1 Faculty of Architectural, Civil and Environmental Engineering, Nam Can Tho University, Can Tho 900000, Vietnam; [email protected] 2 Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Korea * Correspondence: [email protected]; Tel.: +82-51-510-7627 Abstract: The hydrologic characteristic of a permeable friction course (PFC) pavement is dependent on the rainfall intensity, pavement geometric design, and porous asphalt properties. Herein, the hydrologic characteristic of PFC pavements of various lengths and slopes was determined via numerical analysis. A series of analyses was conducted using length values of 10, 15, 20, and 30 m and slope values of 0.5%, 2%, 4%, 6%, and 8% for the equivalent water flow path. The PFC pavements were simulated for various values of rainfall intensity, which ranged from 10 to 120 mm/h, to determine the time taken for water to flow over the PFC pavement surface. The results show that the time for water overflow decreased when the pavement length or rainfall intensity increased, and it increased when the slope increased. Finally, a series of design charts was developed to determine the time taken for water to flow over the PFC pavement surface for given rainfall intensities. Since this study was conducted based on numerical analysis, further studies are recommended to verify experimentally the results presented. Citation: Nguyen, T.H.; Ahn, J. Keywords: hydrologic characteristic; permeable friction course pavement; geometric design Numerical Study on the Hydrologic Characteristic of Permeable Friction Course Pavement. -
Geotechnical Analysis and 3D Fem Modeling of Ville San Pietro (Italy)
geosciences Article Geotechnical Analysis and 3D Fem Modeling of Ville San Pietro (Italy) Rossella Bovolenta * and Diana Bianchi * Department of Civil Chemical and Environmental Engineering, University of Genoa, 16145 Genova, Italy * Correspondence: [email protected] (R.B.); [email protected] or [email protected] (D.B.); Tel.: +39-010-3532505 (R.B.) Received: 21 September 2020; Accepted: 20 November 2020; Published: 22 November 2020 Abstract: The paper describes the three-dimensional numerical model of Ville San Pietro, an Italian village subject to slope movements causing damage. The church (dating back to 1776), which is the most significant building of the area, is modelled too. The information from geotechnical and geophysical surveys on field are used to define the model geometry and the soil properties. A finite element code is adopted to simulate the slope behavior in occurrence of water table fluctuations, detected by piezometers, and to evaluate the slope displacements and stability. The validation of the model is carried out using the inclinometer and interferometry measures and by on-site inspections. The model demonstrated a good ability to simulate the slope behavior during the raising and lowering of the water table. The critical areas computed by the numerical code are in good accordance to the actual portions affected by soil displacements and damages. The modelling presented in this paper is crucial for future analyses that will take advantage of an innovative monitoring system, which will be installed on site. Keywords: numerical modeling; slope stability; 3D model; FEM; hardening soil; landslide; geotechnics; risk mitigation; monitoring 1. Introduction Landslides are common and widespread phenomena in Italy and around the world. -
Sensitivity Study of Different Parameters Affecting Design of the Clay Blanket in Small Earthen Dams
Journal of Himalayan Earth Sciences Volume 48, No. 2, 2015 pp.139-147 Sensitivity study of different parameters affecting design of the clay blanket in small earthen dams Ishtiaq Alam and Irshad Ahmad Department of Civil Engineering, University of Engineering & Technology, Peshawar, Pakistan. Abstract Dams are structures that retain water for human services. Dams may be earthen, concrete, timber, steel or masonry made. On the basis of size, they may be small, medium and large. The main purpose of a dam is to divert the flow of water for the intended use. Flow of water cannot be stopped permanently even by the best dam ever made. Water may seep from dam body, abutments or the foundation bed below the body of the dam. To control seepage from the foundation bed, certain available methods like cutoff trench, cutoff walls, diaphragms, grout curtains, sheet pile walls and upstream impervious blankets are used. Upstream impervious blankets are considered more economical compared with the other methods mentioned above. The key parameters playing role in blanket efficiency are length of blanket, thickness of blanket, clay core width of the dam, foundation bed depth up to impervious zone, reservoir head, permeability of blanket material and permeability of bed material. This study is focused on the effect of these parameters in seepage control. Seep/W, a finite element method based software is used to model all the mentioned parameters within the individually selected ranges. The results based on the software analysis show that when the length of blanket is gradually increased, the seepage quantity reduces gradually until a specific length where the effect of further increase in length become meaningless. -
Two-Dimensional Slope Stability Analysis with Varying Slope Angle and Slope Height by Plaxis-2D
November 2017, Volume 4, Issue 11 JETIR (ISSN-2349-5162) TWO-DIMENSIONAL SLOPE STABILITY ANALYSIS WITH VARYING SLOPE ANGLE AND SLOPE HEIGHT BY PLAXIS-2D Bidisha Chakrabarti 1, Dr. P. Shivananda 2 1 Ph.D. Scholar, 2 Professor Department of Civil Engineering REVA UNIVERSITY, BENGALURU, INDIA Abstract: Stability of Slope is one of the most important sector which should be addressed properly in the area of Geo-technical engineering. The main purpose of this study to determine the Factor of safety and the Displacement vertical as well as horizontal for the given angle of slope of the soil. The stability analysis of the slope has been done here by Finite Element Method using PLAXIS-2D. In this study different types of sequence modelling were conducted here. Every sequence of the model was to investigate for the stability analysis purpose with various slope angle with variable slope height were taken into account. The results of this study showed the different value of Factor of safety for different sequence and comparative study with the displacement. In this paper the value of cohesion and internal friction are taken constant and results compared here for soil with varying slope but for constant two dimensional model. Index Terms: Finite element method, Factor of safety, Drained condition, Displacements I)INTRODUCTION: The focus of this paper is on Numerical Modelling using measurement from a series of set up of systematically sequence set of soil slope and monitored for Finite Element programme by PLAXIS-2D version 8.2 was used here to predict the performance of the slope. -
Common Mistakes on the Application of Plaxis 2D in Analyzing Excavation Problems
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/282997310 Common Mistakes on the Application of Plaxis 2D in Analyzing Excavation Problems Article · January 2014 CITATIONS READS 0 4,815 1 author: Tjie-Liong Gouw Binus University 10 PUBLICATIONS 1 CITATION SEE PROFILE Some of the authors of this publication are also working on these related projects: Shore protection project View project All content following this page was uploaded by Tjie-Liong Gouw on 20 October 2015. The user has requested enhancement of the downloaded file. International Journal of Applied Engineering Research ISSN 0973-4562 Volume 9, Number 21 (2014) pp. 8291-8311 © Research India Publications http://www.ripublication.com Common Mistakes on the Application of Plaxis 2D in Analyzing Excavation Problems GOUW Tjie-Liong Civil Engineering Department, Bina Nusantara University, 11480 Jakarta, Indonesia Email : [email protected] Abstract The advance of computer technology has made the finite element method (FEM) more accessible than ever. Many engineers have tried FEM geotechnical software in handling their geotechnical projects. However, like a pilot with inadequate training, it would backfire if he were to fly a sophisticated jet fighter. Engineers with insufficient geotechnical background may gain access to the sophisticated FEM software without realizing the risk behind it. They make mistakes that may lead to the bad performance or even failure of the geotechnical structures. The author himself, along the years of learning and applying the geotechnical FEM software, has made many mistakes. This paper, with Plaxis application as example, tries to elaborate the common mistakes found in applying the FEM geotechnical software in handling excavation problems. -
FHWA/TX-07/0-5202-1 Accession No
Technical Report Documentation Page 1. Report No. 2. Government 3. Recipient’s Catalog No. FHWA/TX-07/0-5202-1 Accession No. 4. Title and Subtitle 5. Report Date Determination of Field Suction Values, Hydraulic Properties, August 2005; Revised March 2007 and Shear Strength in High PI Clays 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Jorge G. Zornberg, Jeffrey Kuhn, and Stephen Wright 0-5202-1 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Center for Transportation Research 11. Contract or Grant No. The University of Texas at Austin 0-5202 3208 Red River, Suite 200 Austin, TX 78705-2650 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered Texas Department of Transportation Technical Report Research and Technology Implementation Office September 2004–August 2006 P.O. Box 5080 14. Sponsoring Agency Code Austin, TX 78763-5080 15. Supplementary Notes Project performed in cooperation with the Texas Department of Transportation and the Federal Highway Administration. Project Title: Determination of Field Suction Values in High PI Clays for Various Surface Conditions and Drain Installations 16. Abstract Moisture infiltration into highway embankments constructed by the Texas Department of Transportation (TxDOT) using high Plasticity Index (PI) clays results in changes in shear strength and in flow pattern that leads to recurrent slope failures. In addition, soil cracking over time increases the rate of moisture infiltration. The overall objective of this research is to determine the suction, hydraulic properties, and shear strength of high PI Texas clays. Specifically, two comprehensive experimental programs involving the characterization of unsaturated properties and the shear strength of a high PI clay (Eagle Ford clay) were conducted. -
PLAXIS® 2D the Most-Used Application for Geo-Engineering
PRODUCT DATA SHEET PLAXIS® 2D The Most-used Application for Geo-engineering PLAXIS 2D is a powerful and user-friendly finite-element package intended for 2D analysis of deformation and stability in geotechnical engineering and rock mechanics. PLAXIS is used worldwide by top engineering companies and institutions in the civil and geotechnical engineering industry. Applications range from excavations, embankments, and foundations to tunneling, mining, and reservoir geomechanics. PLAXIS is equipped with a broad range of advanced features to model a diverse range of geotechnical problems, all from within a single integrated software package. User-friendly, FE Package PLAXIS 2D add-on modules include PlaxFlow, Dynamics, and Thermal. PlaxFlow excels at making complex 2D groundwater flow analysis easy, while Dynamics offers reliable and comprehensive dynamic load modeling. The Thermal module is necessary when the effects of heat flow on the hydraulic and mechanical behavior of soils and structures need to be taken into account in geotechnical designs with PLAXIS. These modules Stability of embankment on soft soil, reinforced by rigid inclusions. work together to build a powerful and user-friendly finite element package intended for two-dimensional analysis of deformation and stability in geotechnical engineering wizard to quickly create and edit tunnel cross-sections and loading conditions. The and rock mechanics. Mesh mode features automatic and manual mesh refinements, automatic generation of irregular and regular meshes and capabilites to -
International Society for Soil Mechanics and Geotechnical Engineering
INTERNATIONAL SOCIETY FOR SOIL MECHANICS AND GEOTECHNICAL ENGINEERING This paper was downloaded from the Online Library of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). The library is available here: https://www.issmge.org/publications/online-library This is an open-access database that archives thousands of papers published under the Auspices of the ISSMGE and maintained by the Innovation and Development Committee of ISSMGE. General Report of TC103 Numerical Methods Rapport général du TC103 Méthodes numériques Chau K.T. The Hong Kong Polytechnic University, Hong Kong, China ABSTRACT: This general report summarizes 52 papers being included in the TC103 Session on Numerical Methods. Instead of summarized each paper, we have provided an overall view of these papers. A master table (Table 3) is given for all 52 papers in terms of the types of numerical methods empolyed by different authors, together with the full references given at the end of the paper (paper number follows in alphabetic order). The numerical methods used include finite element method (FEM), finite difference method (FDM), material point method (MPM), smoothed particle hydrodynamics (SPH), neural network (NN), genetic algorithm (AG), and finite volume method (FVM). The failure models used in studies include Mohr-Coulomb failure criterion, Drucker-Prager plastic potential, Cam clay model, Matsuoka-Nakai failure model, and Hoek-Brown failure criterion. These numerical analyses have been applied to model piles, tunnels, retaining walls, slopes, levees, tailings impoundment, and breakwaters. Errors of and methods of vailidation for finite element method given by Brinkgreve and Engin (2013) was summarized briefly. Future challenges in numerical methods are outlined. -
Water-Sciences Software Guide
Table of Contents In The Name Of God the Compassionate the Merciful ! "#$% Application of Computers in Water-Sciences :&' ' ) #* Seyyed Javad Hoseiny : +, #./ +- Dr. Mhohamad Aflatuni 84 ) ' August 2005 219 3 -01 ! "#$% ,2/ " +, 34 5 6/ Table of Contents 1 Special Thanks 4 1 2 Abstract 5 2 3 Suggestions 6 3 4 Reason of Importance 7 4 5 Similar Researches 8 5 Detailed Guide for The First 6 9 #$% &' 12 !" # 6 Top 12 Software 7 Where to Find the Software 32 +,) # #$% &' () * 7 8 Software-Course List 33 /# .#$% &' -% 8 9 Rating Method 56 0# 1# 9 10 Initials & Expressions 58 23456 #!78 ,94 10 11 Full Software List 59 ,2/ " 7 6/ 11 12 CD Introduction 201 - %: 12 13 Website Introduction 202 - %: 13 To Those Who Are Whishing to # ;<4 0= >< 14 Continue Researching in This Field 204 14 * ? 15 Contact Us 205 / 15 16 Refrences and Resources 206 @8A B 16 17 What Do You Say? 218 + =C D 17 219 4 -01 ! "#$% ,2/ " +, 8 ' 9' Special Thanks ,' =8 =' #= #= , # # E ;= 'F=G H ? # ) &)D # 8 :;= - =: 3 # * ) (# 7-) '=G4% 7) . (* D N' *#) ' 7-) 2HL ,M' ":0 7) . 7D# # 7) =(' . 5< 5< O4 P=QH #@N' ) #= ,-< 1='% / . (;LS.;-# 7:6 N' R=L#=Q7# =7 7H' R=L# (; * # S 7 )) 'H3 * / . ( L7- Griffith N' 7-) Graham Jenkins 7) . (; /# N' 7-) ,: =0 7) . (VS - E.#- N' 7-) 3 #U T L8 7) . (S Utah State N' # S 7-) Wynn R. Walker 7) . ., # '#< ' Back to Contents 219 5 -01 ! "#$% ,2/ " +, :9-' 8; Abstract '# [7E #) VS &= ;XU36 ;-D#) Y;=(' ;) DS ? * Z .- E ? \ )S *=3 # =T= UG -
Prediction of Bearing Capacity of Bored Cast- in Situ Pile
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN: 2278-1684, p-ISSN: 2320-334X. PP 01-06 www.iosrjournals.org Prediction of Bearing Capacity of Bored Cast- In Situ Pile Sanatombi Thounaojam1, ParbinSultana2 1,2( Dept. of Civil Engg., NIT SILCHAR, Assam, India) Abstract: An axially loaded pile tests have been carried out on 0.6m diameter bored cast in-situ piles in clayey silt soil with decomposed organic matter upto minimum depth of 11m.This paper presents an FEM model for simulating these field axial load tests embedded in such soils using PLAXIS 2D. The simulation is carried out for a single pile with an axial load at pile top, so as to evaluate the settlement of the pile. The vertical load versus settlement plots on single pile is obtained from field tests and are compared with the finite element simulation results using PLAXIS 2D, showing reasonable agreement. Different approaches for estimating the bearing capacity of piles from SPT data have been explained and compared. Statistical and probability approaches were engaged to verify the SPT predictive methods with the log-normal distribution in order to predict the degree of scattering of uncertainty. Keywords: Pile Bearing Capacity, Standard Penetration Test, Finite Element Method, Standard Deviation. I. Introduction Pile foundation is one of the most popular forms of deep foundations. Piles are generally adopted for structures in weak soils, characterized by low shear strength and high compressibility, as well as in good soils, in cases where structures are subjected to heavy loads and moments[1].The maximum settlement of the pile and its ultimate load bearing capacity are the governing criterion in the design of axially loaded piles.