砌体危房加固工程中的静压桩设计与应用

Design and application of a static pile design in strengthening dangerous masonry buildings

提出了 2种桩承台设计方案及多种施加静压力的方案 .在一个 5层砖混结构房屋的加固工程中 ,通过计算 ,直接改钢筋混凝土条形基础作桩承台 ,在该基础上打膨胀螺栓 ,通过传力杆锚固荷载分配梁 ,由它固定反力架 ,从而给桩施加静压力 .实测结果表明 :在砖混住宅中 ,把反力架固定在已建承重墙或基础上 ,通过千斤顶给桩施加静压力 ,能解决场地狭小问题 ,并能消除已有承重墙与基础对桩基础施加静压力时造成的不利影响 ;在砌体危房加固工程中 ,当软弱地基墙下条形基础沉降过大时 ,可优先采用静压桩设计方案加固承重墙下基础 .

Two schemes of pile cap design are proposed, and so are many schemes of static pressure application. For an example, the strip foundations beneath bearing walls are converted straightly into the pile caps through calculation, the counterforce frame is fixed on the load distribution beam which is anchored by the anchor rods, and the anchor piles are again anchored by the anchor bolts on the reinforced concrete strip foundation for the static piles. The static pile construction is accomplished favorably to strength a five layer dangerous masonry building. The results show that the narrow, difficult and disadvantageous effect of the present bearing walls and bases on the static pressure application of piles can be overcome through adjusting jack exerting the static pressure on a pile while the counterforce frame is fixed on the present bearing wall or base in a masonry tenement, the technique of static pile strengthening strip foundation beneath bearing wall in dangerous masonry buildings can be adopted when settlement of bearing walls strip foundation on soft ground base is too large.