高分子合成纤维在管片混凝土中的应用研究

Application Study on Polymer Synthetic Fiber in Segment Concrete

为了解决类矩形盾构管片的裂缝控制及混凝土脆性问题,确保管片尺寸的精度,在混凝土中掺入了高分子合成纤维,研究了其对混凝土性能的影响,并与钢纤维、玻璃纤维的增强效果进行了对比,探讨了高分子合成纤维在管片混凝土中应用的可行性。试验结果表明,高分子合成纤维、钢纤维及玻璃纤维的掺加对地铁管片混凝土工作性和力学性能影响不大,但对混凝土的增韧效果显著,抗弯性能及抗冲击性能得到明显改善。管片混凝土中掺加6 kg/m^3的高分子合成纤维和30 kg/m^3的钢纤维具有同等的增韧效果,可减少或部分取代管片混凝土中非结构配筋用量,提高管片的综合效益。

In order to solve the crack control and concrete brittleness of quasi-recangular segments, the properties of concrete with different kinds of fibers were discussed, such as polymer synthetic fibers, steel fibers, and glass fibers. And the feasibility of polymer synthetic fiber in segment was analyzed. The results show that the mixing of fibers has little influence on the working performance and mechanical properties of concrete, and the toughening effect on concrete is remarkable, the bending resistance and impact resistance of concrete are significantly improved. Toughening effect is almost the same, for Polymer synthetic fibers(6 kg/m^3) and steel fibers(30 kg/m^3), which can reduce or partially replace the amount of non-structural reinforcement in the segment.