Jinsha Bridge Detection And Reliability Analysis Of Bearing Capacity Of Main Beam

Now, the domestic carrying capacity of existing bridges in use often can not meet the design requirements. Many old bridges whose life did not reach the design life have become dangerous bridges. Testing, evaluation and reliability analysis for the existing bridge has become a top priority. In this paper, the bridge assessment methods are applied to the actual project. Since China has not a reliable assessment of the bridge structure specification and existing assessment methods rely on the experience of the evaluators too much, on the basis of the existing reliability assessment methods, we assess the reliability of simply supported bridges. Hope to establish a more reasonable assessment of the reliability theory and practical methods of bridge. The main contents of this paper are:According to damage of the structure, position and width of cracks, concrete strength, and thickness of the protective layer, this paper analyzes the causes of various diseases arising. This paper summarizes the key items of detection methods, the basic principles and processes load testing. This paper analyzes the basic method based on the current assessment of the technical specifications for bridge condition assessment, and final grade was awarded five.In this paper, the characteristics of the existing structures are elaborated and introduce the reliability of existing concepts. This paper analyzes the calculation method of the specific structural reliability and structural system reliability. This paper presents the statistical parameters of dead load effects and live load effects. It consider the impact on the valuation of load effects to correct live load effects and summarizes the resistance factors and statistical laws, considering the actual losses to correct calculation model.In this paper, the actual project as an example, selecte structural failure modes and list limit state equation to calculate the bearing capacity of the reliability index by checking point method. Calculate the correlation coefficient between each main beam with PNET method to analyze a reliable indicator main beam system. According to a reliable indicator of the main beam system level technical condition of the bridge to be assessed, evaluation results are consistent with the results of standardized assessment method, and determine the carrying capacity of the main beam does not meet the requirements. We consider the live load impact on the reliability index, and give a quantitative relationship between the two.In this paper, the detection of bridges, provide the basis for assessing the state of technology. Bridge static load test is conducted in accordance with the actual situation of the bridge. Detailed analysis of the test conditions set layout, deflection and strain measurement points layout, vehicle layout and theoretical calculations. Based on static load test data, calibration coefficients of the main control point is greater than1, and finally determine the carrying capacity of the main beam does not meet the requirements.In order to compare the difference between reliability assessment and standardized assessment, based bridge inspection data obtained, press the 《ighway bridges carrying capacity assessment procedures》 be seized count, to prove the use of the technical condition evaluation of reliability theory is consistent with the existing assessment methods. Assessment methods used herein and the specific implementation process is available for bridge inspection, maintenance workers refer to in their daily work.