连续排水边界条件下考虑界面参数的排水板固结理论研究

沿海地区存在大面积的吹填土地基，在排水固结过程中，地基上下边界面的排水能力显著影响土体固结速率，进而影响吹填土地基沉降预测及有效应力等参数的计算准确度。连续排水边界条件通过引入界面参数能够对传统极限排水边界进行补充，但连续排水边界条件下界面参数的影响因素、取值范围尚未明确，因而连续排水边界条件下的固结理论尚未应用于实际工程计算。基于此，本项目拟通过试验反演，数值分析等方法分析各参数特别是土体孔隙率、渗透系数、砂—土交界面相关性质、砂垫层厚度等对界面透水能力即界面参数影响，建立反应各因素对界面参数影响规律的经验公式，归纳出不同土体对应的界面参数取值范围，并通过现场试验验证结果的可靠性和有效性。进一步完善基于连续排水边界条件的排水板固结理论，为滨海吹填土地基的固结沉降预测及复合地基桩基承载力计算提供更加完善、实用的理论参考。

There exists vast area of hydraulic fill in China. During the drainage consolidation process, the drainage capacity of the upper and lower boundary surfaces of the foundation significantly affects the rate of soil consolidation, which in turn affects the settlement prediction and effective stress, etc. of the dredger fill foundation. Continuous drainage boundary conditions is expected to supplement the traditional limit drainage boundary by introducing interface parameters. However, the influencing factors and value ranges of interface parameters under continuous drainage boundary conditions are not yet clear. Therefore, the consolidation theory under continuous drainage boundary conditions has not been applied to calculations in practical projects. Based on this, this project proposes to analyze the influences of various parameters, especially soil porosity, permeability coefficient, sand-soil interface related properties, sand cushion thickness, etc., on interface water permeability (i.e. interface parameters) through experimental inversion, numerical analysis and other related methods. This project will further establish an empirical formula that reflects the influence of various factors on interface parameters, summarize the value ranges of interface parameters corresponding to different soils, and verify the reliability and validity of the results through field tests. This project then seeks to improve the drainage slab consolidation theory based on continuous drainage boundary conditions, and provide a more complete and practical theoretical reference for the consolidation and settlement prediction of coastal dredger fill foundations and the calculation of the bearing capacity of composite foundation pile foundations.