高速公路结构物“三背”回填施工技术

Construction Technology of“Three Backs”Backfilling for Expressway Structures

高速公路结构物桥台背、涵洞背和挡墙背俗称“三背”,三背回填一般在狭窄场地内进行,为避免结构物受损,大型设备施工受到限制,因此施工质量难以控制,同时三背回填料与结构物的材料以及基础承载力存在较大差异,导致施工后沉降量不一样。若三背回填料选材、施工工艺和质量达不到要求,往往出现三背回填区域沉降现象。结合施工实践简述如何从选材和施工工艺控制上来提高三背回填的施工质量。

The bridge abutment back,culvert back and retaining wall back of Expressway structures are commonly called"Three Backs".Three-Back backfilling is usually carried out in narrow site,and the construction of large equipment is restricted,so the construction quality is difficult to control.At the same time,the material and bearing capacity of the foundation of the three-back filler are quite different from that of the structure,which results in different settlement after construction.If the material selection,construction technology and quality of Three-Back backfill fail to meet the requirements,settlement of three-back backfill area often occurs.Combining with construction practice,this paper briefly describes how to improve construction quality of three backfilling from material selection and construction process control.