大跨度预应力钢箱梁施工关键技术研究

Research on Key Technologies for Construction of Large Span Prestressed Steel Box Beams

研究以交互智能项目20号厂房为例,分析了大跨度预应力箱形梁的复杂施工工况。在综合考虑楼板荷载、钢构件重量、现场施工条件等因素的情况下,研究采用了“楼面拼装焊接+预应力分级张拉+液压整体提升”的施工思路。利用Tekla模型设计深化软件在板面设计并布置了底部分配钢梁作为提升区域钢构件底部支撑系统,以用于钢构件板面的拼装焊接。在钢柱侧面设计、制作并安装液压提升平台,以用于提升区域钢构件组装焊接后的整体液压提升。结合现场施工条件,设计偏心工况下整体液压提升的缓冲装置以及多点同步正反转缓冲电路,保证大跨度预应力箱形梁偏心工况下提升瞬间的稳定性。通过布置底部分配梁、整体液压提升、仿真模拟提升过程、缓冲回正装置等技术措施,确保了液压提升过程中的安全性,最终达到了工期要求。

Taking the interactive intelligence project No.20 factory building as an example,this study analyzed the complex construction conditions of large-span prestressed box girders.Taking into account factors such as floor load,steel component weight,and on-site construction conditions,the study adopted the construction approach of"floor assembly welding+prestressed graded tensioning+hydraulic overall lifting".Using Tekla model design software,a bottom distribution steel beam was designed and arranged on the board surface as the bottom support system for the steel components in the lifting area,for the assembly and welding of the steel component board surface.Design,manufacture,and install a hydraulic lifting platform on the side of the steel column for the overall hydraulic lifting of the assembled and welded steel components in the lifting area.Based on the on-site construction conditions,design a buffer device for overall hydraulic lifting under eccentric working conditions and a multi-point synchronous forward and reverse buffer circuit to ensure the stability of the lifting moment of large-span prestressed box girder under eccentric working conditions.The safety of the hydraulic lifting process was ensured through technical measures such as arranging the bottom beam,overall hydraulic lifting,simulating the lifting process,and buffering and returning devices,ultimately meeting the project schedule requirements.