贫混凝土透水基层的排水能力

Discharge Ability of Lean Cement Subdrainage Base

为研究路面内部排水能力的计算方法、基层渗透系数取值方法以及路面内部退水时间,采用较大尺寸的试验板进行了透水基层排水能力的模拟试验研究,并通过研究变水头时不同坡度、不同孔隙率下的路面退水时间,建立了退水时间、退水百分比、孔隙率和坡度之间的回归公式。研究结果表明:在恒水头条件下,当基层底面水平时,基层的排水能力为达西定律计算值的1/2;当基层底面坡度为s时,基层的排水能力q可近似为q=kh1s;试件的垂直渗透系数和基层渗透系数的概念及数值不同,可以通过修正试件室内垂直渗透系数来获得路面基层渗透系数。建立的回归公式为最终确定路面内部的排水时间标准提供了依据。

In order to study the calculation method of base discharge ability, the method of determining the base permeability coefficient and water discharge time, using the large-size test slab, simulation experiment on discharge ability for permeable base was studied. Regression formulae related to water discharge time, discharge percentage, voids and slope were established with different slopes and pore ratios under conditions of variable water head. It is found that when the slope of base at bottom is on level, the amount of discharge is equal to half of amount calculated by Darcy law. When the slope of base at bottom is s, the amount of water discharge is equal to q = kh1s under the condition of constant water head. Concepts and values of vertical permeability coefficients and base permeability coefficients of sample are different. Base permeability coefficients can be obtained by modifying vertical permeability coefficients of sample in laboratory. The formulae can provide reference for determining base discharge time.