悬臂连续梁挂篮预压方法探讨

DISCUSSION ON PRELOADING METHOD OF HANGING BASKET OF CANTILEVER CONTINUOUS BEAM

随着社会的发展,大跨度连续梁应用越来越普及,利用挂篮可方便地完成悬臂的现浇施工,具有结构轻便、拼装简单,施工速度快等优点。在施工过程中,挂篮承担着施工机械及新浇节段混凝土的所有荷载,其承载力和弹性变形量将影响施工安全及桥梁的线型。为了消除挂篮主桁、吊带及底篮的非弹性变形,保证挂篮各构件的强度、刚度、稳定性,测出挂篮在各级荷载作用下的竖向位移,通过其规律来指导挂篮施工中模板的预拱度值,一般都需要对挂篮进行荷载预压试验。

With the development of society,the application of large-span continuous beams is becoming more and more popular.The cast-in-situ cantilever construction can be easily completed by using the hanging basket,which has the advantages of light structure,simple assembly and fast construction speed.In the construction process,the hanging basket bears all the loads of construction machinery and newly poured segment concrete,and its bearing capacity and elastic deformation will affect the construction safety and bridge line type.In order to eliminate the inelastic deformation of the main truss,sling and bottom basket of the hanging basket,ensure the strength,stiffness and stability of each component of the hanging basket,measure the vertical displacement of the hanging basket under various loads,and guide the camber value of the formwork during the construction of the hanging basket through its rules,it is generally necessary to carry out load preloading tests on the hanging basket.