To expedite the determination of the support elevation adjustment scheme during the girder launching, an optimization method of support elevation adjustment with vertical curvature is proposed. The optimization problem is analyzed for adjusting the support elevation, with the optimization variables, objective functions, and constraints clearly clarified. An optimization method for support elevation adjustment is proposed, based on the principle of “accurately adjusting and optimizing the support elevation for over-limit supports, and then integrating the support elevation adjustment schemes”. The concept of elevation modulus is employed to clarify the principle of support elevation adjustment and to enable stepwise adjustment. MATLAB and ANSYS are used to implement the support elevation optimization program, allowing the rapid determination of the support elevation adjustment scheme. The proposed algorithm is applied to obtain a support elevation adjustment scheme for a steel box girder launching. The results show that, compared with the exhaustive method, the proposed support elevation optimization method increases calculation efficiency by 25 times. It also reduces the steel consumption of the support plates by 69% while ensuring the safety and reliability of structural stresses during the jacking process. This method thus demonstrates significant economic benefits. This study proposes an efficient optimized computational framework for formulating the support elevation adjustment scheme in vertical variable curvature girder during launching procedures.
标高模数设为10 mm. 针对临时墩支反力超限的支点标高,调整总体设置原则,依照“该墩竖直向下调整以减少超限支点受力;临近墩竖直向上调整以分担超限支点受力”的思路设置,进而通过支点标高调整保证结构受力安全合理,具体调整原则见表2. 表内数据列分别表征以下信息:首列标识支反力超限位置;次两列则分别记录待调支点编号及其标高修正方向.
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