振动打桩机打设塑料排水板桩加固软土地基的工程实践

Engineering practice of the plastic drain-sheet-piles for the strengtheningof soft soil foundation

用塑料排水板桩加固地基,是通过排出地基土孔隙水,消散孔隙水压力,减少孔隙比来提高地基固结压力的。在国内插板机制造专业体系尚未形成的情况下,采用DZ40Y型振动桩机施插SPB-I塑料排水板,可使地基承载力提高2倍。与堆载预压法相比,可降低造价l/3,缩短工期1/3;与砂井或碎石桩相比,可降低造价2/3,且不增加工期。

Engineering practice of the plastic drain-sheet-piles for the streng- thening of soft soil foundation has been primarily based on the following factors namely: (1)drainage of water in soil cavity reduces the water pressure in the soil cavity; (2)decreasing the porosity ratio; thus(3) increasing consolidation and strengthening the bearing capacity of soil foundation. As the system of sheet pile driving equipment has not yet completed in our country, the current adoption of DZ 40Y pile-vibrator and of SPB-1 plastic sheet piledrainer have eventually increased the soil bearing capacity 2-fold. While in comparison with the accumulative preloading method, it has saved the cost by 1/3, and shortened workdays by 1/3. Besides, compar- ing with method of sand well or of crush-stone pile, it has saved the cost by 2/3 and duly completed on time schedule.