排水板真空度损耗的排水固结解析解

无砂真空预压吹填软土在国内造地工程中广泛应用,但实践表明传统固结解析解已不足以预测其加固性状和加固效果。从固结方程出发,在原有的等应变假设基础上,在定解条件中增加了吹填土特有的高度欠固结特性和无砂真空预压特别明显的真空度损耗,重新推导得到径向和竖向完全协调的新的等应变解析解——JJJ解答,以解决无砂真空预压吹填软土的排水固结设计理论问题。JJJ法作为固结方程的原生解答,兼容以往所有该类解析解的同时,增加了针对高度欠固结土类和排水板真空度损耗严重的排水固结问题的解决能力。经现场和试验验证,JJJ解析解可相当精确预测无砂真空预压吹填软土的复杂固结过程和加固土体超孔压分布和孔压消散分布,该解答同时也适用于堆载和真空预压的工况。

Analytical solutions to drainage consolidation considering vacuum loss in prefabricated vertical drain

The non-sand-cover (NS) vacuum preloading (VP) has been widely used in China. Based on the equal-strain assumption, a new set of analytical solutions to consolidation drainage under VP and NS-VP, called JJJ-solution, are developed from original equations by Terzaghi and Barron for vertical and radial drainage, by introducing the original definite conditions, that is, highly under-consolidated initial state of soil and severe vacuum loss along PVD drain boundary. The JJJ-solution is consistent with all the existing equal-strain solutions and verified through experiments. It is capable of accurately predicting the unusual dissipation and distribution of the excess pore-water pressure in consolidation under NS-VP on soft-muddy foundation. In addition, the JJJ-solution is suitable for simulating soil consolidation in general vacuum, surcharge and vacuum-surcharge preloading.