宁波城市地面沉降物理数学模型及沉降预测

根据宁波市地面沉降分层标历年观测数据,用不同的物理模型描述它们的压缩、回弹特征。将可能选用的沉降物理模型和分层标观测数据进行最优拟合,应用这种非线性规划(SUMT)的Powell最优化方法来求解宁波地面沉降的主要压缩层的变形数值,其结果表明宁波地面沉降处于主固结阶段。将宁波地面沉降数学总模型视为各土层变形之总和。各土层的计算主要的参数亦通过最优化方法进行反算求得。利用总模型所得的沉降计算值和同一地层结构区地面水准点实测数据进行比较获得满意的结果。将总模型外推则可预测同一地层结构区今后若干年内沉降数值。以上全部工作将由计算机完成。

PHYSICAL MATHEMATICS MODEL AND PREDICTION ON SUBSIDENCE OF NINGBO CITY

Based on observations of the settlement gauge in each year and their respon-dence characteristics of deformation, two physical models can be used to describe the mechanism of consolidation of soil layers in Ningbo area. Then, the nonlinear program(SUMT)optimum method of Powell is used for computing deformation value of the main compressible layers. The analysis results have shown that the deformation state of the subsidence in Ningbo area is still on the stage of primary consolidation. If the total value of the subsidence in Ningbo area is assumed to be equal to the sum of each layer deformation, the main mechanical parameters of each layer can be obtained by back analysis, Using the optimum method. It also shows that the model is satisfied with the measuring data of the subsidence in Ningbo area.The model also can be used to predict the value of the subsidence in furture. All of analyses of the physical mathematics model will be completed by the computer.