Expansion of a thick cylinder of sand: a laboratory simulation of the pressuremeter test

The Paper discusses a series of tests in a thick cylinder apparatus in which a cylindrical cavity was expanded a thick cylinder of sand with both frictionless ends and fully rough ends. The testing forms part of an investigation of the pressuremeter test in sand. The main aim this phase of the programme was to determine whether the values of the parameters obtained from the test could be influenced by the fact that the pressuremeter of finite length, i.e. whether there were any end effects the test. To determine the influence of the finite radius of the sand sample compared with the infinite dimensions relevant to the in situ test, the pressure-expansion behaviour of the thick cylinder was analysed using simple soil model based on that used by Hughes, Windle and Wroth in their analysis of the in situ test. This demonstrated that the laboratory test is a rather poor simulation of the in situ test. However, the good agreement between the behaviour observed and that predicted indicates that, if end effects c...