等应变连续加载k_0固结试验研究

采用等应变连续加载试验方法,对西安地铁二号线原状黄土进行了k0固结试验。通过试验数据的分析可知静止土压力系数k0随含水率增大而增大,割线模量随轴向应力的增大,表现为先减小后增大的变化趋势。研究表明:由于原状土的结构性影响,割线模量的变化可以分为加荷瞬间割线模量最大、荷载增大割线模量减小、超过硬化荷载后割线模量增大这三个阶段,在此基础上得出黄土地基沉降量计算公式。

Research on Isostrain Continuous Loading k_0 Consolidation Test

The k0 consolidation test is carried out for the undisturbed loess in Xi'an Metro Line No.2 by using the isostrain continuous loading consolidation method.Through the analysis of test data,it is known that the stationary earth pressure coefficient k0 would be increases with the increasing of axial stress.The study results show that because of the structural impact of undisturbed soil,the change of secant modulus could be divided into three stages,such as the secant modulus being maximum in instant loading,the secant modulus decreasing with loading increasing,and the secant modulus increasing after over-hardened loading.Based on this,the calculation formula for the ultimate sedimentation of loess is obtained.