Fredrick Lekarp

• Doctor of Philosophy
• KTH Royal Institute of Technology

The present paper attempts to explore the impact of grading scale, or changes in maximum particle size of graded aggregates, on triaxial test results. The study is based on a series of repeated load triaxial tests on three unbound granular materials at different grading scales. The experimental results show clearly that the structural response obse...

The permanent strain behavior of unbound aggregates under repeated loading has been studied by many researchers over the years. A summarized review of the research into this area is given based on the literature available to date. Different views from various sources are outlined and discussed. A state of the art is presented regarding the factors...

The findings of an extensive literature survey on the structural response of unbound aggregates are discussed in two companion papers. In this paper, a state of the art is presented on resilient stress-strain characteristics of such materials, as well as different modeling techniques. The resilient response of aggregates is affected by several fact...

The development of a large-scale repeated load triaxial testing apparatus is described. The apparatus uses a 500x1000 mm specimen and is capable of testing granular materials with up to 100 mm particle size at cyclic deviatoric and confining stresses. Full details of the equipment are given together with information on its performance. The work des...

A state of the art is presented on modelling permanent deformation behaviour of unbound granular materials. The existing numerical models are verified by a series of laboratory repeated load tests. A new model is introduced expressing the accumulated permanent axial strain at any given number of cycles as a function of applied stresses, taking into...

The results of a research program aimed at characterizing the permanent deformation behaviors of different types of unbound aggregates under repeated loading are summarized. Tests were performed in a triaxial or hollow-cylinder apparatus, depending on the grading of the materials. The scope of the research was to assess the relationship between tot...

The results of a research program aimed at characterizing the permanent deformation behaviors of different types of unbound aggregates under repeated loading are summarized. Tests were performed in a triaxial or hollow-cylinder apparatus, depending on the grading of the materials. The scope of the research was to assess the relationship between tot...