Abstract:
The problems and solutions of applying the bender element method to determine the maximum shear modulus
Gmax) of sand are investigated by conducting resonant columnRC) and bender elementBE) tests on four dry sands obtained from Germany. The study indicates that the start-to-start method is more reliable to identify the time of shear wave propagation in specimens compared to other methods. In BE tests, the excitation frequency of input waves has influence on the tested
Gmax, and this influence is dependent on soil types and reduced by increasing confining pressure. A comparison between RC and BE tests shows that
Gmax by both methods may be well expressed as a linear equation; for the Berlin sand and Braunschweig coarse sand, there exists a threshold
Gmax below which
Gmax by BE tests
GmaxBE)) is greater than that by RC tests
GmaxRC)), however beyond which the
GmaxBE) is smaller than
GmaxRC) and the distance between both increases with increasing stiffness soil. In practice, it is suggested that the input voltage with proper high frequency is preferred for BE tests, as compared with RC tests.