利用高性能钢纤维混凝土制备新型覆工板

Application of High Performance Steel Fiber Reinforced Concrete for Road Deck Panel

针对覆工板的性能需求(混凝土坍落度为(250±25)mm,扩展度为(600±100)mm,流动时间≥30 s,28 d抗压强度为70 MPa),进行了高性能混凝土配比的研发,依据致密配比逻辑设计了高性能混凝土配比并制备了高性能纤维(钢纤维、聚丙烯纤维)混凝土.经配比验证显示,高性能钢纤维混凝土的力学性能最佳,其28 d抗压强度可大于80 MPa、抗弯强度大于9.5 MPa,故选用高性能钢纤维混凝土进行新型覆工板的制作与验证.结果表明,以高性能钢纤维混凝土制作的新型覆工板初始开裂载重为原始设计值(12 t)的4倍以上,经实际铺设测试,均表现出良好的力学性能及安全性能.高性能钢纤维混凝土覆工板不仅耐久性较好,而且还不需二次施工,其材料成本比传统钢制覆工板节省一半以上.

The mixtures of high performance concrete（HPC） and high performance steel fiber reinforced concrete（HPSFRC,added steel and polypropylene fibers） are designed by the densified mixture design algorithm.The workability of concrete must satisfy comply with the requirement that slump is（250±25） mm,slump flow is（600±100） mm,and flow time is over 30 s and the compressive strength is 70 MPa at 28 d.The test results show that HPSFRC has the best mechanical properties（（e.g.,） compressive strength is over 80 MPa and flexure strength is over 9.5 MPa at 28 d）.Therefore,HPSFRC is adopted to make the road deck panel and prove its performances.The results reveal that the initial cracking load of HPSFRC road deck panel is over 4 times of the designed value（（i.e.） 12 t）.After the test of pavement in site,such road deck panels have very nice properties.The HPSFRC road deck panel mot only has better durability but also lower cost of only half of traditional steel deek panel.