赣中红砂岩填料路基动态模量现场影响因素研究

Study on Field Influencing Factors of Dynamic Modulus of Red Sandstone Subgrade in Central Jiangxi Province

掌握红砂岩填料路基动态模量的现场变化规律,通过现场便携式落锤式弯沉仪(PFWD)试验、室内粉晶X射线衍射(XRD)试验和现场压实度试验,分析了不同黏土矿物含量、含水率和压实度对红砂岩填料路基动弹性弹模量的影响。结合现场检测数据,建立了动态模量随压实度和含水率变化以及动态模量随黏土矿物含量、含水率和压实度变化的试验回归模型。研究表明:现场的红砂岩填料路基动态模量与压实度具有良好的正相关回归关系。成型路基的含水率普遍比施工时高。红砂岩填料路基的动态模量随含水率增大而减小,二者具有良好的回归关系。XRD试验显示:动态模量随黏土矿物含量的增大而减小,二者也具有良好的回归关系。此外,不但动态模量与压实度、稠度这2个指标具有良好的回归关系,而且动态模量与压实度、稠度、黏土矿物含量3个指标也均具有良好的回归关系。

In order to know the variation regularity of the dynamic modulus of red sandstone subgrade in field, the field portable falling weight deflectometer （PFWD） test, the indoor powder X -ray diffraction （XRD） test and the field compactness test are carried out. The effects of mineral contents, water contents, and compactness of different clays on the dynamic modulus of red sandstone subgrade are analyzed. The regression model of dynamic modulus varies with compactness and water content, and the regression model of dynamic modulus varies with clay mineral content, water content and compactness are established based on the field detection data. The results show that （ 1 ） the dynamic modulus of the tested subgrade is closely positive regressively correlated with the compactness; （2） after construction, the water content is higher than that under construction; （3） the dynamic modulus of the tested subgrade decreases with the increase of the water content, and they have a good regression relation. The XRD test shows that （1） the dynamic modulus decreases with the increase of clay mineral content and they have a good regression relation too; （2） not only there is a good regression relation of dynamic modulus with compactness and consistency, but also there is a good regression relation of dynamic modulus with compactness, consistency and clay mineral content.