铺装层超高性能混凝土密配钢筋的通过性研究

Study on Passing Ability through Dense Reinforcement Mesh of Ultra-high Performance Concrete for Paving Layers

钢桥面超高性能混凝土铺装层普遍采用高钢纤维掺量和密配筋的设计方案。超高性能混凝土拌合物对密配筋的通过性,直接影响实际铺装工程施工的效率与质量,亟需考察与解决。通过不同的试验方法考察了钢纤维体积掺量3.5%的UHPC拌合物的密配钢筋通过性能,指出UHPC拌合物的密配筋间隙通过性能随着其流动性的提高而增加,并以筛孔边长与实际密配筋间隙接近的方孔筛通过率试验较好的反应UHPC拌合物的密配筋间隙通过性;同时,较小流动度的UHPC拌合物需要配合较长的平面振动时间实现密配筋间隙通过与模板空间的密实填充。

The design scheme of high steel fiber content and dense reinforcement are widely used in the ultr-high performance concrete(UHPC)pavement of steel bridge decks.The passing ability of UHPC mixture through the dense reinforcement mesh directly affects the efficiency and quality of the construction,which needs to be investigated and solved.In this paper,with different test methods,the passing performance of UHPC mixture with 3.5%steel fiber through dense reinforcement mesh is investigated.We claim that the passing performance of UHPC mixture through dense reinforcement mesh increases with the improvement of its fluidity.The passing rate test of square hole sieve whose side length of the square hole is close to the actual dense reinforcement gaps can better reflect the passing performance of UHPC mixture.The UHPC mixture with less fluidity needs a longer plane vibration time to pass the dense reinforcement gap and filling the formwork space well.