真空预压法沉降计算经验系数取值方法的研究

Method of empirical coefficient of settlement calculation with vacuum preloading method

采用真空预压法处理软土地基时,目前还缺少资料计算最终沉降值的经验系数。国家规范GB 50007-2011的公式和行业标准JTS 147-2-2009的公式都可用来计算沉降值。它们的公式不同,但原理相同,所以结果也应该相同,借此可获得经验系数取值的方法。用国家规范GB 50007-2011的公式计算时,土的压缩模量应取用实际压力对应的值。用行业标准JTS 147-2-2009的公式计算时,应考虑真空压力的衰减。选择各自合适的经验系数,使两种计算方法所得的沉降曲线重叠,即可得到各自的沉降经验系数。通过某变电站的实例,推演获取经验系数的方法,其结果用实测资料验证,取得满意的效果。

There is no information on calculating the empiriccal coefficient of final settlement value when the soft soil foundation is treated by the vacuum pre-loading method.The formula of national standard GB 50007-2011 and the formula of industry standard JTS 147-2-2009 can be used to calculate the settlement value.They have different formulas,but the same principles and the same results.Therefore,the empirical coefficient can be obtained.The compressive modulus of the soil should be taken from the value corresponding to the actual pressure when calculating with the formula of the national standard GB 50007-2011.The attenuation of the vacuum pressure should be considered when calculating by the formula of the industry standard JTS 147-2-2009.By selecting the appropriate empirical coefficients,the settlement curves obtained by the two calculation methods are overlapped,and the respective settlement experience coefficients can be obtained.Through the example of a substation,the method of obtaining the empirical coefficient is derived,and the results are verified by the measured data,which can give the satisfactory results.