高速铁路路基工程观测期不足沉降控制技术研究(Ⅰ)超载原则和设计  

Study on Settlement Control Technology of Insufficient Observation Period of High-speed Railway Subgrade Engineering(Ⅰ)Surcharge Preloading Principle and Design Approach

作　　者：陶明安 TAO Ming’an(China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308

出　　处：《铁道标准设计》2022年第12期11-14,共4页Railway Standard Design

基　　金：中国铁路设计集团有限公司科研课题(2020YY340625)。

摘　　要：高速铁路路基工程建设中由于预压期不足,超载补强措施尚缺乏成熟的设计与计算方法,因此需要从定性阶段向定量阶段转化。基于超载预压须提前卸载至等载预压的理念和沉降固结计算理论,系统构建了高铁路基沉降观测期不足超载补强实施原则和设计方法:(1)确定了天然基底或桩板结构的桩底为强风化或弱风化基岩时地基不需补强,其他工况如工后沉降满足规范要求时,可有条件地实施定性补强原则;(2)在明确超载卸载时机和卸载沉降标准建议值的基础上,提出超载补强的计算与设计流程;(3)指出今后工程应用过程中沉降评估卸载、工点检算以及周边施工环境影响等方面需要注意的事项。在技术可靠、经济合理的前提下,最大限度保障路基工程满足如期评估、卸载与铺轨等方面的要求。In the construction of high-speed railway subgrade engineering,there is still a lack of advanced design and calculation methods for surcharge preloading with insufficient preloading period,which needs to be transformed from the qualitative stage to quantitative calculation stage.Based on the concept that surcharge preloading must be unloaded to equal preloading in advance and the settlement consolidation calculation theory,this paper systematically establishes the implementation principle and design method of surcharge preloading for high-speed railway subgrade with insufficient preloading period:(1)it is determined that the foundation does not need to be reinforced when the natural base or pile bottom of the pile-plate structure is strongly or weakly weathered bedrock;and it can be qualitatively reinforced conditionally under such other working conditions as when the post-construction subsidence meets the requirements of specification;(2)On the basis of determination the overload unloading time and the recommended value of unloading settlement standard,the calculation and design process ofsurcharge preloading are put forward;(3)The matters needing attention in settlement evaluation,unloading,site checking and calculation,and the impact of surrounding construction environment in future engineering application are pointed out.On the premise of reliable technology and reasonable economy,the requirements of on-time evaluation,unloading and track laying of the subgrade works shall be maximally satisfied.

关 键 词：高速铁路 路基工程 超载预压 观测期不足 补强原则 卸载时机 

分 类 号：U213.1[交通运输工程—道路与铁道工程] U238