Abstract The structural performance will be improved if certain amount of short steel fibers are added into the or? dinary concrete. The steel fiber reinforced concrete has been applied in the above-ground structure but there is no application case in metro shield tunnels in marine stratum by the sea, so the relevant technical indexes and design parameters should be further studied and perfected. Based on the Xilihu-Xili running tunnel of Shenzhen metro, a study on steel fiber reinforced concrete segment of metro shield tunnel in marine stratum was conducted by laboratory test, and the results show that: 1) various kinds of strengths of concrete are improved attributed to steel fibers; 2)it is significant to have reasonable steel fiber length and reasonable proportion of course aggregates with maximum grain size to improve the flexural strength of concrete segment; 3) sand ratio change has significant effect on workability of mixture; 4) the proportion of steel fibers should be reasonable; 5) the micro-crack of fiber reinforced concrete is reduced, the pore structure is improved and the permeability of segment is improved thanks to steel fibers.
Abstract：
The structural performance will be improved if certain amount of short steel fibers are added into the or? dinary concrete. The steel fiber reinforced concrete has been applied in the above-ground structure but there is no application case in metro shield tunnels in marine stratum by the sea, so the relevant technical indexes and design parameters should be further studied and perfected. Based on the Xilihu-Xili running tunnel of Shenzhen metro, a study on steel fiber reinforced concrete segment of metro shield tunnel in marine stratum was conducted by laboratory test, and the results show that: 1) various kinds of strengths of concrete are improved attributed to steel fibers; 2)it is significant to have reasonable steel fiber length and reasonable proportion of course aggregates with maximum grain size to improve the flexural strength of concrete segment; 3) sand ratio change has significant effect on workability of mixture; 4) the proportion of steel fibers should be reasonable; 5) the micro-crack of fiber reinforced concrete is reduced, the pore structure is improved and the permeability of segment is improved thanks to steel fibers.
ZHENG Aiyuan1 XU Bin2 CHEN Xiangsheng1
.Study on Material Performance of Steel Fiber Reinforced Concrete Segments for Subway Shield Tunnels in Marine Stratum[J] MODERN TUNNELLING TECHNOLOGY, 2019,V56(5): 211-217
2019, Vol. 56 