开采沉陷动态预计的正态分布时间函数模型研究

Study on normal distributed time function model to dynamically predict mining subsidence

使用常用的Knothe时间函数进行煤炭开采所引起的地表动态下沉预计时,其反映的地表下沉速度和下沉加速度与地表实际下沉规律不相符,基于此,可引入一种新的时间函数—正态分布时间函数,对该时间函数值的变化范围和变化规律进行了详细对比,给出了正态分布时间函数用于地表动态预计时参数的确定方法,并利用该时间函数对某矿区地表下沉实测数据进行了对比预测。研究表明:正态分布时间函数的下沉速度和下沉加速度与地表动态下沉规律是相吻合的;当进行不同精度的动态预计时,合理选择函数的形态参数非常重要;在某些矿区,利用正态分布时间函数进行动态预计比使用双参数Knothe时间函数进行预计更符合地表移动的变化规律,预计结果也更为可靠。

When a conventional Knothe Time Function was applied to predict the surface ground dynamic subsidence caused by the coal mining,the surface ground subsidence speed and subsidence acceleration reflected were not fitted with the actual subsidence law of the surface ground.Based on the circumstance,the paper introduced a new time function- normal distributed time function.A detail comparison analysis was conducted on the variation scope and variation law of the time function value. The normal distributed time function was provided to the method to determine the surface ground dynamic predicted time parameters.The time function could be applied to the comparison prediction on the real measured data of the surface ground subsidence in a mining area.The study showed that the subsidence speed and the subsidence acceleration of the normal distributed time function could be fitted with the surface ground dynamic subsidence law.When a different accuracy dynamic prediction was conducted,the morphological parameters of the rational selected function would be very important.In a mining area,the normal distributed time function applied to the dynamic prediction would be closely fitted to the variation law of the surface ground movement than the prediction with the double parameters Knothe Time Function and the predicted results would be more reliable.