The Crack Prevention And Optimization Of Pre-camber Of Research On Continuous Rigid Frame Bridge

Cracks in the concrete structure issues prevalent. Continuous rigid frame bridge structure because of its cross-section of a larger size, longer span, the construction process of complex, high cost, its prevention and treatment of cracks more attention. In this paper,the author of the Zhongtang Bridge and so to participate in five continuous rigid frame bridge construction monitoring tasks, as well as the Han River Bridge, the long-term monitoring tasks for the engineering background, familiar with the bridge construction process, master the development of these cracks in the bridge form, At the same time, domestic and foreign experts will study the structure of cracks in summing up the results, the control and management of continuous rigid frame bridge of effective measures to crack. At the same time, Han River Bridge by Bridge deflection change operation 3 years comparing the measured and theoretical study on the continuous rigid frame bridge construction control of pre-camber optimization are discussed. The main results related to the following:1. Analysis of the concrete continuous rigid frame bridge type and the causes of structural cracks at the same time, summed up the classification of the various manifestations of the cracks, and cracks in the analysis of the construction, the construction of the structure through cracks and structural cracks during operations research, made in the structure of continuous rigid frame bridge design should be effective to grasp the key points to prevent the cracks.2. The contraction of the concrete structure of the larger, the paper shrinkage cracks on the concrete mechanism for analysis of the proposed control concrete shrinkage cracks on the structure of effective measures.3. The cracks are inevitable, can only be carried out through a variety of effective control measures, cracks, mainly generated in the construction phase. Thesis of continuous rigid frame bridge girder cracks location, development patterns have been studied for the prevention and control measures of these cracks, respectively, by design measures and construction measures studies.4. Combined with a bridge at the scene measured the temperature field data, using the finite element analysis software ANSYS10.0 after pouring concrete to produce the greatest temperature difference between heat of hydration, the box the temperature effect, the Committee observed that in the heat of hydration, the bridge box girder Concrete stress generated can not be ignored, or even greater than the tensile strength of concrete in the structure of weak parts, such as prestressed reserved temperatures near the pipeline, such as cracks, and cracks have been observed at the scene to verify the actual. 5. According to the Red Bridge Village hydration heat of concrete pouring temperature effect study, the effective control and to avoid temperature and hydration heat recommendations.6. Summed up the bridge of the commonly used method to deal with cracks and determine the method of load cracks.7. To the continuous rigid frame bridge bridge operation in the presence of inter-torsion phenomenon in the study measured. Han River Bridge through the construction of long-term monitoring data analysis, derived for the continuous rigid frame bridge construction control of the pre-camber the formula and the formula to deal with the use of the environment.