公路路堤软土地基工后沉降的三参数预估模型

3-parameter Prediction Model of Post-construction Settlement for Soft Soil Foundation Under Highway Embankment

引入沉降半衰期的概念,结合初始沉降速率、最终沉降量,建立了路基工后沉降-时间曲线模型的数学特征方程,揭示了传统指数模型和双曲线模型的数学缺陷。基于能量耗散假定,建立了工后沉降-时间关系的三参数模型,并从数学上严格证明了指数模型是三参数模型的上界,双曲线模型是三参数模型的下界,它们均是三参数模型的简化形式。研究结果表明:三参数模型性质与理想工后沉降曲线一致,其克服了2种传统模型的不足。工程实测进一步证明了三参数模型的正确性。

Combined with initial settlement rate and final settlement volume, half-value time of settlement is employed to build the mathematical property equations of post-construction settlement-time curve model for soft foundation under highway embankment. The mathematical deficiencies of exponential model and hyperbolic model were revealed. 3-parameter model for post-construction settlement-time was established based on energy dissipating assumption. Mathematical proof shows that the exponential model and hyperbolic model are up boundary and low boundary of the new established model respectively. Research results show that new established model overcomes the deficiencies of exponential model and hyperbolic model and its mathematic property satisfies the request of ideal settlement curves. The accuracy of the new model was proved by the engineering case.