Dynamic elastic modulus for frozen soil from the embankment on Beiluhe Basin along the Qinghai-Tibet Railway

摘要

Dynamic tri-axial tests were conducted to study the dynamic properties of the frozen soil from the embankment on Beiluhe Basin along Qinghai-Tibet Railway. The dynamic tri-axial tests included frozen soil samples subjected to fifteen test events with five different temperatures, five different water contents and five different confining pressures. Experimental expressions of the frozen soil parameters are obtained, including the maximum dynamic elastic modulus, the dynamic elastic modulus ratio, and the reference linear strain amplitude, based on the test data and an equivalent linearization model. The effects of temperature, water content and confining pressure on the dynamic elastic modulus ratio and the backbone curves of the frozen soil are discussed. The results provide basic experimental data for establishing dynamic constitutive law of the frozen soil and meaningful information for further studies on dynamic response of railway embankment in the permafrost regions caused by passing train.