公路软基超载预压卸荷沉降速率标准研究  

STUDY ON THE SETTLEMENT RATE STANDARD FOR DETERMINING THE SURCHARGE REMOVAL TIME FOR EMBANKMENT ON SOFT GROUND

作　　者：杨涛[1] 周有成[1] 李聪[1] 

机构地区：[1]上海理工大学土木工程系,上海200093

出　　处：《工业建筑》2009年第12期70-73,共4页Industrial Construction

基　　金：上海市教委科技发展基金资助项目(05EZ02)

摘　　要：软土地基上的路基施工常采用沉降速率法确定超载卸荷时间。现有的沉降速率法主要依据地方经验沉降速率标准,无法与获得的工后沉降相联系。基于分级加荷条件下地基固结度计算的改进太沙基公式,推导出超载沉降速率与等载工后沉降间的关系式,据此建立按容许工后沉降控制的超载预压卸荷沉降速率标准。有限元数值模拟分析表明,相对于地方经验沉降速率标准过于严格,该沉降速率标准卸荷控制的工后沉降满足规范要求。通过应用于实际工程,给出了超载卸荷时间。Settlement rate method is often used to decide surcharge removal time for embankment on soft ground. Postconstruction settlements controlled by empirical settlement rate standards used in some highways can not be obtained. A equation that describes the relationship between settlement rate during surcharge preloading and the post-construction settlements is derived by means of Terzaghi＇ s consolidation theory for multistage loading. The settlement rate standards relevant to the allowed post-construction settlements are presented based on this equation. Numerical simulation analysis shows that the post-construction settlements controlled by the regional empirical settlement rate standards are much more less than the allowed values, the settlements controlled by the proposed settlement rate standards meet the requirement of specifications. Finally, one case history is analyzed to verify the use of the proposed standards.

关 键 词：超载预压 沉降速率标准 工后沉降 卸荷时间 

分 类 号：U416.1[交通运输工程—道路与铁道工程]