真空排水预压工程中孔压实测资料的分析与应用

Analysis of field test data on pore pressure in vacuum drainage preloading

总结真空排水预压工程中决定孔压变化的因素,分析各因素在真空排水预压过程中对孔压变化的影响模式.提出了一种由真空排水预压工程孔压现场实测资料来推算抽真空在地基中形成的负压渗流场分布模式的方法,使之应用于若干工程的分析,得到各工程抽真空时负压渗流场沿地基深度的分布模式,并对其分布规律做了初步探讨.当塑料排水板打设深度在20m以内时,由该方法分析得到的负压渗流场分布模式沿深度基本一致,其值在膜下真空度的50%以上.当塑料排水板打设深度在20m以上时.由该方法分析得到的负压渗注场分布模式有一定离散性.

Factors influencing the variation of pore pressure in vacuum drainage preloading were determined and analyzed to develop a method to obtain the distribution of the seepage field of negative pore pressure along the depth of soft soil foundation. Some vacuum drainage preloading projects were analyzed using this method and the distribution regularity of the seepage field of negative pore pressure along the depth of soft soil foundation was determined. When prefabricated vertical drains (PVDs) were installed to a depth less than 20 m, the distribution along depth was almost consistent and the value was greater than 50% of applied vacuum pressure. When PVDs were installed to a depth more than 20 m, the distribution presented a certain extent dispersion.