基于摄像测量的斜拉桥索导管精确定位技术

Research on Precise Positioning Technique for Stay Cable Guide Tubes of Cable-Stayed Bridge Based on Videometrics

斜拉桥索导管的定位可以利用安装劲性骨架、钢内导管等传统方法来实现.在钢斜拉桥索导管安装施工中索导管的出口中心坐标可以利用传统索导管定位的方法来直接测得,但是索导管锚固点由于位于钢主塔内部而无法直接测定,给索导管的定位造成了较大的难度.将摄像机应用到钢斜拉桥索导管定位中来可以巧妙的解决传统方法的不足之处.根据摄像测量技术的原理,推导定位技术的计算公式,现场实测索导管锚固点的投射位置坐标,根据计算公式算出索导管的锚固点坐标,调整索导管的空间位置,实现索导管的精确定位.将该方法应用到一座钢斜拉桥施工中,可简便、易行的实现对索导管的精确定位.

Currently,the positioning of stay cable guide tubes of cable-stayed bridge can be realized through traditional ways such as installing rigid skeletons and internal steel guide tubes and etc.In the installation of stay cable guide tubes in cable-stayed bridge of steel structures,the bottom center coordinates of the tubes can be measured directly through the traditional positioning way,but the anchoring points of stay cable guide tubes can not be measured directly as they are located inside the main tower of cable-stayed bridge,posing great difficulty for the positioning of stay cable guide tubes.Using cameras in positioning of stay cable guide tubes is an effective way to avoid the shortcomings of traditional methods.Based on the principle of videometrics technology,precise positioning of stay cable guide tubes can be realized by deducing the calculation formula of positioning technology,measuring the projection position coordinates of the anchoring point on site,calculating the anchoring point coordinates of the cable guide tubes,and adjusting the spatial position of the tubes.Application of the method to construction of a cable-stayed bridge of steel structure contributes to precise and easy positioning of stay cable guide tubes.