Analysis of flexible pavements incorporating nonlinear resilient behavior of unbound granular layers

Download

index.pdf

Date

2004

Author

Karagöz, Cem

Metadata

Show full item record

Item Usage Stats

278
views

591
downloads

Traditionally, the resilient modulus values obtained from repeated unconfined or triaxial compression tests are used as the elastic modulus of granular layers in structural analysis of flexible pavements. Sometimes the resilient modulus of granular materials are estimated from known California bearing ratios (CBR) or stabilometer resistance (R) values by simple regression equations. On the other hand, it is well known that stress-strain relation for unbound granular materials is nonlinear and the resilient modulus increases with the increase in stress intensity. There exist several models for stress dependent nonlinear behavior of unbound granular materials. These models are incorporated into elastic layered analysis by applying a method of successive approximations in order to get more realistic pavement responses. Kenlayer is a popular computer program incorporating nonlinear behavior of granular materials in elastic layered system. In this computer program, the resilient modulus of granular materials are varied in vertical direction only, without considering variations in radial direction. In this study, simplest model namely K-Q model for stress dependency of granular layer is applied in structural analysis of flexible pavements. This model is adopted for use in finite element analysis carried by SAP90 software. Analyses are performed over 24 different three-layered pavement structures by changing asphaltic concrete modulus values, granular base thicknesses, base materials and subgrade modulus values. Critical pavement responses namely tensile strains at the bottom of asphaltic surface layers and compressive strains on top of subgrade are obtained for each pavement by linear layered elastic, nonlinear layered elastic and nonlinear finite element solutions. The pavement lives are calculated by using selected performance equations. The results of layered systems and

Subject Keywords

Transportation engineering.

URI

http://etd.lib.metu.edu.tr/upload/2/12605320/index.pdf
https://hdl.handle.net/11511/14462

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

A computational procedure for estimating residual stresses and secondary plastic flow limits in nonlinearly strain hardening rotating shafts Eraslan, Ahmet Nedim (Springer Science and Business Media LLC, 2005-03-01) A computational procedure to estimate the residual stress distributions and the limit angular speeds for avoiding secondary plastic deformation in nonlinearly strain hardening rotating elastic-plastic shafts is given. The model is based on von Mises yield condition, J(2) deformation theory and a Swift-type hardening law. The boundary value problem for the governing nonlinear differential equation is solved by a shooting method using Newton iterations with numerically approximated tangent. Solid as well as h...
Analysis of specimen size effects in inclined compression test on laminated elastomeric bearings Topkaya, Cem (Elsevier BV, 2004-07-01) Inclined compression test method is a practical way of determining the shear modulus of full-size laminated elastomeric bearings. Performing full-size bearing tests requires high-capacity testing machines. It may be possible to cut the specimens into smaller sizes for testing purposes. Limited amount of experimental data show that specimen size has a significant effect on the measured shear modulus. In this paper, the Haringx shear weak column theory is used to identify the important geometric specimen prop...
A computer simulation of void dynamics under the action of electromigration and capillary forces in narrow thin interconnects Ogurtani, TO; Oren, EE (2000-10-25) In these studies a comprehensive picture of void dynamics in connection with the critical morphological evaluation has been thoroughly anticipated in order to understand main reasons as well as the conditions under which premature failure of metallic thin interconnects occur. Our mathematical model on diffusion and mass accumulation on void surfaces, under the action of applied electrostatic potential and capillary effects, follows a novel irreversible but discrete thermodynamic formulation of interphases a...
Analysis of the flexural strength of prestressed concrete flanged sections Baran, Eray; French, Catherine (Precast/Prestressed Concrete Institute, 2005-01-01) Inconsistencies in the sectional response of prestressed concrete flanged sections predicted by the AASHTO LRFD and AASHTO Standard Specifications, including the maximum reinforcement limits, may arise due to different interpretations of the equivalent rectangular compressive stress block idealization. Strain compatibility analyses with nonlinear material properties were performed for a variety of non-rectangular prestressed concrete sections to identify the inconsistencies between the two specifications. R...
A methodology for lining design of circular mine shafts in different rock masses Öztürk, Hasan (2016-09-01) In this study, the finite element numerical modelling of 2D shaft sections in a Hoek-Brown medium are carried out in a non-hydrostatic stress state in an attempt to predict pressures developing around mine shafts. An iterative process of applying support pressure until observing no failure zone around the shaft is used to simulate the required lining support pressure for different shaft models. Later, regression analysis is carried out to find a generic shaft pressure equation representing the rock mass and...

Citation Formats

C. Karagöz, “Analysis of flexible pavements incorporating nonlinear resilient behavior of unbound granular layers,” M.S. - Master of Science, Middle East Technical University, 2004.