Externally Prestressed Of Long-span Concrete Continuous Box Girder Bridge When Tensioning Construction Monitoring

Variable cross-section concrete continuous box girder bridge because of its beautiful appearance, good structural performance, has become more and more widely used. But with the increase of bridge spans, improving construction technology requirements, the construction process is becoming more and more complex, and the bridge itself but also affected by factors such as temperature, humidity, time, therefore, internal force and displacement of the bridge is also becoming more and more complex, the changes of how to make the bridge construction process control, comply with the design requirements to ensure that the bridge internal force and displacement is the long-span concrete variable cross-section continuous box girder bridge construction. Based on the highway, Buddha-geely river bridge reinforcement as the research background, revolves around concrete variable cross-section box girder bridge construction monitoring research. Through targeted monitoring of reinforcement of bridge in the process of bridge construction factors such as stress, strain and displacement, temperature change, and the corresponding theoretical analysis, macro quality to ensure that the construction of Bridges and bridge structure safety.1. This article provides a complete set of monitoring content flow, and introduces the measuring point arrangement, to monitor the deformation, stress and strain of the bridge, box girder temperature field, tension and crack.2. This article has carried on the overall monitoring and real-time monitoring, its temperature, tension, deflection and strain of the data, to ensure the normal operation of the structure of the bridge.3. The structure of each construction stage of real-time monitoring results were compared with the theoretical calculation results analysis, timely analysis of the structure of the difference between measured values and the theoretical calculation value, accurate grasp each construction process under the state of the structure, ensure the safety of the structure in the construction process, at the same time, the reinforcement effect of the structure of the reasonable evaluation of basic data, as a structure in the later operation process for the long-term monitoring of the initial data accumulation.This project cases for the bridge reinforcement, the reinforcement method for applying externally prestressed cable structure, the results show that the prestressed cable can improve the compressive stress of structure is applied in vitro reserves, reinforcement effect achieved the design purpose and requirements.