基于回弹强度的泥岩风化程度分析

Investigation of Weathering Rate of Mudstone Using Rebound Values

泥岩极易风化,往往对工程施工造成许多不利影响。以内蒙古神华新准铁路巴准线下侏罗统泥岩路基为例,根据不同位置和不同时刻的泥岩回弹值测试结果,使用回弹监测值与时间的关系来表述风化速度,研究了泥岩的风化速度及其空间变化情况,提出了回弹值预测的双曲线模型。结果表明,随历时增加,各测点回弹值下降很快;这一变化趋势在不同测点之间并没有明显区别;双曲线模型比指数模型更能反映回弹值随时间的变化情况,拟合优度从0.7533～0.8612提高到0.9157～0.9739。本文成果对泥岩风化速度研究与泥岩地区工程施工具有一定的参考价值。

mudstone is much easily to be weathered and exhibits a negative influence on the construction.In the current study,taking the mudstone subgrade at railway as an example,the field rebound monitoring values were obtained at various locations at different time,the weathering rate was defined as the change between the rebound monitoring values at different time.The weathering rates and their change at various locations were examined.A hyperbolic model representing the change of the rebound values was thereafter proposed.It shows that the rebound values decrease quickly at different locations and have no significant differences in tendency;by comparison with the exponent model,the hyperbolic model may be better to reflect the tendency of the rebound values as time passed and have a fit goodness from 0.7533 to 0.8612 in the former model increasing to 0.9157 to 0.9739 in the latter one.The results presented herein may be referable both in investigating the weathering rate of a mudstone and in the practical construction in the mudstone areas.