Development of a Constitutive Model for Resilient Modulus of Cohesive Soils

Development of a Constitutive Model for Resilient Modulus of Cohesive Soils
Author: Dong Gyou Kim
Publisher:
Total Pages:
Release: 2004
Genre: Soil mechanics
ISBN:

Abstract: The objective of this study was to evaluate existing constitutive models currently used by State Department of Transportations (DOTs) and to develop an improved model for predicting resilient modulus (Mr) of cohesive soils from simple soil properties typically measured in DOT laboratories in preference to expensive and complex Mr laboratory testing. The data set used consisted of cohesive soils typical of those used for subgrades in Ohio. Thirteen representative cohesive soils representing A-4, A-6, and A-7-6 soil types collected from road construction sites across Ohio, were tested in the laboratory to determine their basic engineering properties. Mr tests were conducted at three different moisture contents (dry of optimum moisture content, optimum moisture content, and wet of optimum moisture content). Additional tests were performed on samples compacted to optimum conditions but allowed to fully saturate. Mr predicted from six existing models studied showed wide scatter and poor correlation with the measured Mr. An improved constitutive model was developed to account for the effects on Mr of the stress state of the soil and its engineering properties obtained from simple laboratory tests. While most of the existing models investigated in this study significantly overestimated the Mr of a cohesive soil, the proposed model predictions are close to the experimental values and are in most cases a slight underestimation. This implies that Mr values predicted by the proposed model are generally slightly conservative, and can be safely used in the design of flexible pavements to be built on cohesive soils. The proposed model can be a useful and reliable tool for estimating Mr of cohesive subgrade soils using basic soil properties and the stress state of the soil.

Practice of Constitutive Modelling for Saturated Soils

Practice of Constitutive Modelling for Saturated Soils
Author: Zhen-Yu Yin
Publisher: Springer Nature
Total Pages: 417
Release: 2020-09-11
Genre: Science
ISBN: 9811563071

This book describes the development of a constitutive modeling platform for soil testing, which is one of the key components in geomechanics and geotechnics. It discusses the fundamentals of the constitutive modeling of soils and illustrates the use of these models to simulate various laboratory tests. To help readers understand the fundamentals and modeling of soil behaviors, it first introduces the general stress–strain relationship of soils and the principles and modeling approaches of various laboratory tests, before examining the ideas and formulations of constitutive models of soils. Moving on to the application of constitutive models, it presents a modeling platform with a practical, simple interface, which includes various kinds of tests and constitutive models ranging from clay to sand, that is used for simulating most kinds of laboratory tests. The book is intended for undergraduate and graduate-level teaching in soil mechanics and geotechnical engineering and other related engineering specialties. Thanks to the inclusion of real-world applications, it is also of use to industry practitioners, opening the door to advanced courses on modeling within the industrial engineering and operations research fields.

Determination of Resilient Modulus Values for Typical Plastic Soils in Wisconsin

Determination of Resilient Modulus Values for Typical Plastic Soils in Wisconsin
Author: Hani Hasan Titi
Publisher:
Total Pages: 316
Release: 2011
Genre: Pavements
ISBN:

The objectives of this research are to establish a resilient modulus test results database and to develop correlations for estimating the resilient modulus of Wisconsin fine-grained soils from basic soil properties. A laboratory testing program was conducted on representative Wisconsin fine-grained soils to evaluate their physical and compaction properties. The resilient modulus of the investigated soils was determined from the repeated load triaxial (RLT) test following the AASHTO T307 procedure. The laboratory testing program produced a high-quality and consistent test results database.

Characterization of Subgrade Resilient Modulus for Virginia Soils and Its Correlation with the Results of Other Soil Tests

Characterization of Subgrade Resilient Modulus for Virginia Soils and Its Correlation with the Results of Other Soil Tests
Author: M. Shabbir Hossain
Publisher:
Total Pages: 32
Release: 2008
Genre: Soils
ISBN:

In 2004, the Guide for the Mechanistic-Empirical Design of New & Rehabilitated Pavement Structures (MEPDG) was developed under NCHRP Project 1-37A to replace the currently used 1993 Guide for Design of Pavement Structures by the American Association of State Highway and Transportation Officials, which has an empirical approach. Implementation of the MEPDG requires the mechanistic characterization of pavement materials and the calibration of performance prediction models by the user agencies. The purpose of this study was (1) to determine the resilient modulus values for Virginia's subgrade soils for input into MEPDG design/analysis efforts, and (2) to investigate the possible correlation of the resilient modulus with other soil properties. Although the MEPDG provides default values and correlations for resilient modulus, they are based on a limited number of tests and may not be applicable for Virginia soils and aggregates. The possible correlation of the resilient modulus with other soil properties was investigated because such correlations could be used for smaller projects where costly and complex resilient modulus testing is not justified. More than 100 soil samples from all over Virginia representing every physiographic region were collected for resilient modulus, soil index properties, standard Proctor, and California Bearing Ratio testing. Resilient modulus values and regression coefficients (k-values) of constitutive models for resilient modulus for typical Virginia soils were successfully computed. There were no statistically significant correlations between the resilient modulus and all other test results, with the exception of those for the quick shear test, for which the correlation was very strong (R2 = 0.98). The study recommends that the Virginia Department of Transportation's Materials Division (1) implement resilient modulus testing for characterizing subgrade soils in MEPDG Level 1 pavement design/analysis, and (2) use the quick shear test to predict the resilient modulus values of fine soils using the relationships developed in this study for MEPDG Level 2 design/analysis

Constitutive Modeling of Soils and Rocks

Constitutive Modeling of Soils and Rocks
Author: Pierre-Yves Hicher
Publisher: John Wiley & Sons
Total Pages: 340
Release: 2013-03-01
Genre: Technology & Engineering
ISBN: 1118621492

This title provides a comprehensive overview of elastoplasticity relating to soil and rocks. Following a general outline of the models of behavior and their internal structure, each chapter develops a different area of this subject relating to the author's particular expertise. The first half of the book concentrates on the elastoplasticity of soft soils and rocks, while the second half examines that of hard soils and rocks.

Novel Issues on Unsaturated Soil Mechanics and Rock Engineering

Novel Issues on Unsaturated Soil Mechanics and Rock Engineering
Author: Laureano R. Hoyos
Publisher: Springer
Total Pages: 243
Release: 2018-10-29
Genre: Science
ISBN: 3030019357

This volume discusses issues related to unsaturated soil mechanics and rock engineering based on technical papers focusing on two important topics in geotechnical engineering: (1) the characterization of unsaturated soils, and (2) the investigation of rock properties. The research studies on unsaturated soils include the characterization techniques of the unsaturated soils. The studies on rock properties include thermo-hydro-mechanical behavior of gypsum rock, soft rocks capacity, role of rock strength in blastability, indirect methods to estimate rock strength, and variations in isotope distributions in Permian rocks. The two broad themes in this collection, as summarized above, are representative of local challenges facing geotechnical engineers in the Middle East, but their contributions can also be extended to other regions of the world. The volume is based on the best contributions to the 2nd GeoMEast International Congress and Exhibition on Sustainable Civil Infrastructures, Egypt 2018 – The official international congress of the Soil-Structure Interaction Group in Egypt (SSIGE).