摘要
针对钢桥塔的装配施工中,传统的人工预装配过程耗时耗力、效率低下且难以对实际装配过程中的整体线形进行调控分析等问题,建立了基于点云的高精度曲线钢桥塔整体虚拟装配系统方法,降低钢桥塔节段制作误差、自重和温度等受力变形偏差和实际装配过程误差对桥塔整体线形的影响.首先,开展基于节段点云模型的曲线钢桥塔整体虚拟装配,以降低节段制作误差的影响.通过三维激光扫描仪优化扫描方案对各钢节段进行扫描,获取钢节段点云数据并进行点云预处理、参数化建模.基于各节段参数化点云模型,提出了利用RBF神经网络进行轴线预测的曲线钢桥塔节段三点空间定位方法,对钢桥塔节段进行虚拟装配.然后,结合某桥上塔柱的实际工程案例,通过逆向叠加桥塔自重和温度的施工变形,消除施工受力变形.针对实际施工过程中已产生的节段装配误差,利用“施工控制”的思想,通过对其后续节段装配控制点坐标的调整,逐步降低前期节段装配误差对整体线形的影响,进一步提高了曲线钢桥塔的整体装配精度.最后,对建成的花篮形上塔柱进行整体扫描并与设计模型进行了对比,验证了上述系统方法对提高曲线钢桥塔实际装配施工精度的积极作用,为类似复杂钢结构的装配施工提供了技术参考.
The traditional manual preassembly procedure for steel bridge towers is time-consuming,labor-intensive,and inefficient,and it is difficult to control and analyze the overall line shape during the actual assembly process.Thus,a point cloud-based high-precision overall virtual assembly system method was established to reduce the effect of segment manufacturing errors,self-weight and temperature(force deformation deviations),and actual assembly process errors on the overall line shape of steel bridge towers.First,to reduce the effect of segment manufacturing methods,the overall virtual assembly of curved steel bridge towers was realized using the segment point cloud model.The scanning plan was optimized using a three-dimensional laser scanner to scan each steel segment,obtain the point cloud data of the steel segment,and perform point cloud preprocessing and parametric modeling.A three-point spatial positioning method for curved steel bridge tower segments using radial basis function neural networks for axis prediction was proposed,and the steel bridge tower segments were virtually assembled based on the parameterized point cloud model of each segment.Thereafter,the construction deformation of the weight and temperature of the tower was reversely superimposed on an actual engineering case of a tower column on a bridge to eliminate the construction deformation.Subsequently,because of the segment assembly errors that occurred during the actual construction process,the concept of“construction control”was used to gradually reduce the effects of the assembly errors of the previous segment on the overall alignment by adjusting the coordinates of the subsequent segment assembly control points to improve the overall assembly accuracy of the curved steel bridge tower.Finally,an overall scan of the completed flower basket-shaped upper tower column was conducted and compared to the design model.The results demonstrated that the above system method improved the actual assembly construction accuracy of curved steel bridge towers and provided a technical reference for the assembly and construction of similar complex steel structures.
作者
梁栋
蒲洁
赵恺
张子舒
江志刚
Liang Dong;Pu Jie;Zhao Kai;Zhang Zishu;Jiang Zhigang(School of Civil and Transportation,Hebei University of Technology,Tianjin 300401,China;Hebei Steel-Concrete Composite Bridge Technology Innovation Center,Xingtai 054001,China;Hebei Expressway Yanchong Preparation Office,Zhangjiakou 075400,China)
出处
《天津大学学报（自然科学与工程技术版）》
EI
CAS
CSCD
北大核心
2022年第8期828-838,共11页
Journal of Tianjin University：Science and Technology
基金
国家自然科学基金资助项目(51978236)
河北省交通运输厅科技项目(YC-201912)
天津市交通运输委员会科技发展计划项目(2019-06).
