水平腹筋对RPC简支梁抗剪性能的影响
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摘要
通过3根配置水平腹筋高强钢筋RPC简支梁的剪切破坏试验,探究水平腹筋配筋率对试件的裂缝开展、挠度变化和抗剪承载力等的影响,并构建水平腹筋RPC简支梁抗剪承载力计算公式。研究结果表明:水平腹筋RPC简支梁在加载初期,无论是跨中截面还是剪跨区截面均基本符合平截面假定,但是斜裂缝开展后,剪跨区截面的应变平截面假定随即消失;水平腹筋类似纵筋的销栓作用,对试验梁的斜裂缝宽度和抗剪承载力均有一定影响,配筋根数和排数越多,试验梁的斜裂缝宽度越小,抗剪承载力越高;基于拉-压杆桁架模型,考虑活性粉末混凝土在拉-压复合应力状态下的软化现象,构建水平腹筋RPC简支梁抗剪承载力计算公式,其计算结果与试验值吻合较好。
Through the shear test of 3 RPC beams with high strength steel bars, the influence of horizontal reinforcement ratio on the crack development, deflection and shear capacity of the specimens is investigated. A formula for calculating the shear capacity of RPC simply supported beams with horizontal reinforcement is established. The results show that when RPC beam with horizontal reinforcement in the early stage of loading, both middle section and cross section of shear span are basically consistent with the plane cross-section assumption; horizontal reinforcement has a definite effect on the diagonal crack width and the shear capacity. The more numbers of steel bar and numbers of row, the smaller the diagonal crack width of the test beam is, and the higher the shear bearing capacity. Based on the pull-compression truss model, considering the softening behavior of reactive powder concrete under tension compression combined stress, a formula for calculating the shear capacity of RPC simply supported beam with horizontal reinforcement is established. The calculated results match the experimental values.
Through the shear test of 3 RPC beams with high strength steel bars, the influence of horizontal reinforcement ratio on the crack development, deflection and shear capacity of the specimens is investigated. A formula for calculating the shear capacity of RPC simply supported beams with horizontal reinforcement is established. The results show that when RPC beam with horizontal reinforcement in the early stage of loading, both middle section and cross section of shear span are basically consistent with the plane cross-section assumption; horizontal reinforcement has a definite effect on the diagonal crack width and the shear capacity. The more numbers of steel bar and numbers of row, the smaller the diagonal crack width of the test beam is, and the higher the shear bearing capacity. Based on the pull-compression truss model, considering the softening behavior of reactive powder concrete under tension compression combined stress, a formula for calculating the shear capacity of RPC simply supported beam with horizontal reinforcement is established. The calculated results match the experimental values.
引文
[1]张浦.基于软化桁架理论的RPC梁斜截面抗剪承载能力研究[D].北京:北京交通大学,2011.
[2]季文玉,丁波,安明喆.活性粉末混凝土T形梁抗剪试验研究[J].中国铁道科学,2011,32(5):38-42.
[3]邓宗才,陈春生,陈兴伟.混杂纤维活性粉末混凝土梁抗剪性能试验研究[J].土木工程学报,2015,48(5):51-60.
[4]金凌志,梅臣.配箍率对高强钢筋RPC梁抗剪性能影响研究[J].铁道科学与工程学报,2016,13(4):711-716.
[5]金凌志,周家亮,蒋春松,等.配箍率对不同剪跨比RPC梁受剪性能的影响分析[J].华侨大学学报(自然科学版),2017,38(1):38-44.
[6]金凌志,周家亮,李月霞,等.高强钢筋活性粉末混凝土梁受剪性能试验研究[J].建筑结构学报,2015,36(S2):277-285.
[7]刘超,徐栋.腹部纵向配筋混凝土梁斜截面抗剪承载力[J].同济大学学报(自然科学版),2008,36(12):1611-1615.
[8]Vecchio F J,Collins M P.The modified compression-field theory for reinforced concrete element subjected to shear[J].ACI Journal,Proceedings,1986,83(2):219-231.
[9]MacGregor J G,Walters J R V.Analysis of inclined cracking shear in slender reinforced concrete beams[J].ACI Journal,Proceedings,1967,64:644-653.
[10]付国平,熊进刚.有腹筋钢筋混凝土短梁受剪承载力计算的软化桁架模型[J].南昌大学学报(工科版),2004,26(2):62-65.
[11]赵国藩.高等钢筋混凝土结构学[M].北京:机械工业出版社,2005:461-462.
[2]季文玉,丁波,安明喆.活性粉末混凝土T形梁抗剪试验研究[J].中国铁道科学,2011,32(5):38-42.
[3]邓宗才,陈春生,陈兴伟.混杂纤维活性粉末混凝土梁抗剪性能试验研究[J].土木工程学报,2015,48(5):51-60.
[4]金凌志,梅臣.配箍率对高强钢筋RPC梁抗剪性能影响研究[J].铁道科学与工程学报,2016,13(4):711-716.
[5]金凌志,周家亮,蒋春松,等.配箍率对不同剪跨比RPC梁受剪性能的影响分析[J].华侨大学学报(自然科学版),2017,38(1):38-44.
[6]金凌志,周家亮,李月霞,等.高强钢筋活性粉末混凝土梁受剪性能试验研究[J].建筑结构学报,2015,36(S2):277-285.
[7]刘超,徐栋.腹部纵向配筋混凝土梁斜截面抗剪承载力[J].同济大学学报(自然科学版),2008,36(12):1611-1615.
[8]Vecchio F J,Collins M P.The modified compression-field theory for reinforced concrete element subjected to shear[J].ACI Journal,Proceedings,1986,83(2):219-231.
[9]MacGregor J G,Walters J R V.Analysis of inclined cracking shear in slender reinforced concrete beams[J].ACI Journal,Proceedings,1967,64:644-653.
[10]付国平,熊进刚.有腹筋钢筋混凝土短梁受剪承载力计算的软化桁架模型[J].南昌大学学报(工科版),2004,26(2):62-65.
[11]赵国藩.高等钢筋混凝土结构学[M].北京:机械工业出版社,2005:461-462.