Research on Optimization Design of the Mix Proportion of Xiamen Second East Passage Tunnel

Because of the poor hydration heat and shrinkage of the tunnel constructed in sections, structural cracks are easy to occur, and the concrete mix ratio is very important. In order to achieve accurate concrete mix proportion, the paper has optimized the concrete mix proportion of Xiamen East Second Passage. The early mechanical properties and impermeability of the concrete before and after the optimization of the mix ratio were tested. The results show that the cement content in the original design mix proportion is high, the early strength of concrete is excessive, and high hydration heat and shrinkage are easy to occur during construction. The early mechanical properties and impermeability of the optimized mix proportion concrete can meet the design and construction requirements. The conclusions can provide guidance for the construction of similar projects.he construction of similar projects.