Chapter 2 Literature Review

2.1 Introduction

This chapter presents a literature review on the two main topics related to this study,which are the non-coaxiality of soil behaviour and a hollow cylinder apparatus.The chapter is organized in the following structure.Section 2.2 deals with the non-coincidence between the axes of principal stress and principal strain increment in granular materials,including the definition of non-coaxiality and a general introduction of the previous studies using both numerical simulations and laboratory experiments.Section 2.3 introduces the hollow cylinder apparatus,which can be used to investigate the effect of principal stress rotation as well as the influence of anisotropy.The fundamental principles to interpret the state of stress and strains,as well as stress distribution,specimen geometry selection,boundary effects and membrane errors are presented.A review of the development of the hollow cylinder apparatus is also given in this section.Section 2.4 presents the studies on non-coaxial soil behaviour particularly by using the hollow cylinder apparatus.Finally,Section 2.5 summarizes this chapter.