工程重大设计变更后混凝土施工方法改进——以N-J水电站首部工程为例

巴基斯坦N-J水电站首部工程在施工阶段发生了重大设计变更,变更方案中混凝土结构具有体型复杂、配筋率高、多级配混凝土混合浇筑等特点;施工上具有混凝土仓位分散、月浇筑强度高、浇筑难度大等特点。通过对变更后的首部工程设计资料和现场施工条件反复研究,并对多套施工方案进行对比论证,最终形成了较优化的施工方案。工程实践表明,变更方案不仅保证了混凝土施工能够安全、顺利、高强度地连续进行,确保了工程工期;而且实现了混凝土施工质量和成本的有效控制,值得类似工程借鉴和参考。

Improvement of concrete construction method after major design change of main works:case of Neelum-Jhelum Hydropower Station

In the engineering implementation phase, the major design was changed in main works of Neelum-Jhelum Hydropower Station in Pakistan. The concrete structure in the changed plan has the characteristics such as complicated outline, high steel-reinforcement ratio and mixed pouring of multi-grading concrete, and in its construction, the difficulties such as scattered working faces, high monthly work intensity and great execution difficulty, etc. existed. Through reiterative studies on the changed design drawings and field construction conditions, as well as comparative evaluation on various construction solutions, a final optimized solution was formed, which ensured a safe, smooth, highly intensive and continuous execution of concrete construction and the project construction schedule. Moreover, the quality and cost of concrete works had been properly controlled. 