建筑荷载作用下城市地面沉降地理信息模型——以天津市东南部沉降区为例

密集建筑群以及高层建筑荷载引发的地面沉降是一个日益严重的城市灾害问题.本文以天津市东南沉降区为例,从地理信息模型基本理论和建筑荷载引发地面沉降的机制出发,综合考虑了建筑容积率、土壤竖向应力、压缩层厚度、土体压缩模量、地下水的埋深和弱透水层渗透性6个诱发因子对沉降的影响,构建了建筑荷载作用下城市地面沉降地理信息模型.通过实际应用和ROC检验,模型的AUC值达到0.85,证明此模型能够准确清晰地反映沉降变形的大小和趋势,从而为城市地面沉降的分析与计算、总结建筑荷载作用下城市地面沉降的变形规律奠定了基础.

Geographical information model of urban land subsidence induced by building load——case of south-eastern subsidence area in Tianjin

Land subsidence induced by dense buildings and high-rise building load is an increasingly serious urban disaster problem.Influence of six major related factors are considered:building floor area ratio,vertical soil stress,soil layer thickness,soil compression modulus,ground-water depth and ground-water permeability.A geographical information model of urban ground subsidence was proposed.Geographical information model theory and ground subsidence mechanism induced by building load were considered in the model.This model was found to show accurately and clearly subsidence deformation value and trend for the south-eastern subsidence area in Tianjin.The results were validated by receiver operating characteristic,area under curve was found to be 0.85.Therefore the present work provides some basis for analysis and numeration of land subsidence and summary of subsidence discipline induced by building load in urban area.