公路路基土体改良下承载力学特性试验研究——以清云高速公路为例

Research on Bearing Mechanical Property Test of Highway Subgrade under Soil Improvement——Taking Qingyuan-Yunfu Expressway as an Example

为研究清云高速公路软弱路基在不同改良设计、物理环境影响下的承载力学变化,文章采用了力学试验方法,对5种改良剂、不同干~湿路径下改良土试样应力、应变进行了宏观分析。试验表明,改良剂类型不会改变试样应变发展特点,水泥固化剂试样承载应力最高,泡沫固化剂试样承载能力最弱。干~湿路径下,围压对应变特征的影响大于干~湿路径作用。干~湿路径下含水率变化差距越大,则峰值应力越低,围压增大,会限制干~湿作用对承载应力的削弱效应。

In order to study the bearing mechanical changes of the weak subgrade on Qingyuan-Yunfu Expressway under the influence of different improvement designs and physical environments,this paper adopts mechanical test methods to conduct macroscopic analysis of stress and strain of the improved soil samples under five kinds of modifiers and different dry-wet paths.The test shows that the type of modifier will not change the strain development characteristics of the sample,the bearing stress of the cement curing agent sample is the highest,and the bearing capacity of the foam curing agent sample is the weakest.Under the dry-wet path,the influence of confining pressure on strain characteristics is greater than that of dry-wet path.The larger the difference of water content change under dry-wet path,the lower the peak stress and the larger the confining pressure,which will limit the weakening effect of dry-wet effect on bearing stress.