堆积体湿化试验及其状态相关弹塑性模型模拟

Wetting Test on Deposit andIts State-Dependent Elastoplastic Model Simulation

通过双线法大型三轴湿化试验,研究了较密与较松两种密实度的土石混合堆积体,在不同围压σ3下湿化前后力学特性的变化规律,分析了湿化对土石混合堆积体的割线模量E_(50)、临界状态摩擦角、峰值状态摩擦角以及临界状态线位置的影响。结果表明,湿化作用会引起堆积体的割线模量E_(50)、临界状态摩擦角与峰值状态摩擦角的衰减,明确了土石混合堆积体湿化前后的等向固结线(ICL)与临界状态线(CSL)的变化趋势。基于无黏性土的状态相关本构模型,对湿化前后的堆积体应力应变关系进行了模拟,与试验结果对比,发现该模型较好地反映了堆积体湿化前后的剪胀特性变化。

The mechanical characteristics of soil-rock mixed accumulation with dense and loose compacts before and after wetting under different confining pressuresσ3 are studied by a large-scale triaxial slaking test using the dualline method.The effects of wetting on secant modulus E_(50),critical state friction angle,peak state friction angle and the position of critical state line are analyzed.Test results show that the wetting effect can attenuate the secant modulus E_(50),critical state friction angle and peak state friction angle.The changing trend of Isotropic compression line(ICL)and critical state line(CSL)of the mixed deposits of soil and rock before and after wetting are clarified.Based on the state-dependent constitutive model of cohesionless soil,the stress-strain relationship of the deposit before and after wetting was simulated.Compared with the test results,it is found that the model simulation result can reflect the change of the dilatancy character of the deposit before and after wetting.