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目的:非饱和土的弹性剪切模量是预测土体变形和土工建筑物正常使用服役性能的重要参数之一。本文旨在提出一个描述非饱和土弹性剪切模量的简化模型,减少标定模型参数所需要的耗时非饱和土试验,并考虑吸力、应力、干湿循环及孔隙比对弹性剪切模量特性的影响。创新点:1.提出考虑滞回效应的非饱和土弹性剪切模量简化模型;2.减少标定模型参数所需要的试验。方法:1.基于前人非饱和土弹性剪切模量试验结果,考虑非饱和土中土颗粒间的平均骨架应力及毛细水提供的法向应力作用,通过理论推导建立非饱和土弹性剪切模量的半经验简化模型;2.通过文献中不同非饱和粉土及砂土的弹性剪切模量试验结果验证简化模型的适用性。结论:1.得到一个描述非饱和土弹性剪切模量的简化模型,该模型仅需两个模型参数,减少了标定模型参数所需要的耗时非饱和土试验;2.通过四组不同非饱和土弹性剪切模量试验数据验证了简化模型的适用性,表明该模型能考虑吸力、应力、干湿循环以及孔隙比对弹性剪切模量特性的影响;3.由于进行了简化,该模型可能存在少量预测误差,在宽应力和吸力范围内运用该模型时需要谨慎。
Objective: The elastic shear modulus of unsaturated soils is one of the most important parameters for predicting soil deformation and serviceability of geotechnical structures. This paper aims to present a simplified model describing the elastic shear modulus of unsaturated soils and to reduce the time-consuming unsaturated soil tests required to calibrate the model parameters. Considering the effects of suction, stress, wet-dry cycles and void ratio on elastic shear modulus Effect of characteristics. Innovations: 1. Proposed a simplified model of elastic-shearing modulus of unsaturated soils considering the effect of hysteresis; 2. Experiments required to reduce the parameters of the calibration model. Based on the experimental results of elastic shear modulus of unsaturated soils in previous years, considering the average skeleton stress between soil particles and the normal stress provided by capillary water in unsaturated soils, the elastic shear of unsaturated soils Semi-empirical simplified model of the modulus; 2. The applicability of the simplified model is verified by the elastic shear modulus tests of different unsaturated silts and sand in the literature. A simplified model describing the elastic shear modulus of unsaturated soils is obtained. The model only needs two model parameters, which reduces the time-consuming unsaturated soil test required to calibrate the model parameters.2. Saturated soil elastic shear modulus test data verify the applicability of the simplified model, indicating that the model can take into account the suction, stress, wet-dry cycle and porosity ratio on the elastic shear modulus characteristics; 3. Due to the simplification, the The model may have a small amount of prediction error and caution is needed when applying the model over wide stress and suction ranges.