Construction Control And Stress Analysis In The Forming Of Continues T-frame Bridge

The paper present the accidence conclusions of structure analysis and construction control of continuous beam bridge as follows in the light of theoretical analysis and construction control of YANGJIALING Bridge.1. Prestress effect, concrete shrinkage and creep and temperature gradient stress are typical nonlinear problem in time and space. Prestress effect and concrete shrinkage and creep can be solved with the help of equivalent section technique and Finite Element Method (FEM) of displacement respectively. Temperature gradient can be calculated by Finite Volume Model that commended first in this paper. It is necessary to point out that FEM and Finite Difference Model (FDM) are unstable in simulation. The difficulty exists to structure analysis in-depth. And research in-depth should be needed. The calculated results would be modified with the help of experience.2. Precamber include structure precamber, prestress lose precamber, concrete shrinkage and creep precamber, traveling carriage.3. Least square method (LSM) is the full-blown technique in recognition of parameter and employed broad. The LSM would be modified when it is employed to estimate noncontinuous parameters and to count beam rigidity. Stress and distortion measurement should be carried out carefully.4. Increment analysis technique is recommended in FEM when material and geometry nonlinearities were taken into account due to easy to understand and operation.5. There are two structure analysis techniques:positive and reverse structure analysis. Each one can do structure analysis and have own predominance. Positive structure analysis technique more better simulate construction course of bridge and present stress and displacement in subsection. Relative factors (such as structure nonlinearity and concrete shrinkage-creep) can be considered in bridge forming. Reverse structure analysis technique is intent on gaining install elevation and stress of the perfect state in construction course.6. Example:YANGJIALING T-frame bridge (span 112+200+112m). The technique (structure analysis, construction control, side span and middle span closure) mentioned above have been applied in the example. The precamber is the top important. In order to modify precamber structure parameters were used in positive ang reverse analysis. The jacking force, which must be estimated in the light of pier rigidity and modified by experience, is the key point in bridge closure.