集中荷载下高强箍筋混凝土梁的抗剪性能

Shear behavior of reinforced concrete beam with high-strength stirrup under concentrated load

通过8根集中荷载下高强箍筋混凝土梁的受剪破坏试验,分析了500 MPa箍筋混凝土构件斜截面的剪切承载力及使用阶段的斜裂缝宽度,同时对两组配有蒙皮钢筋的混凝土梁的受剪承载力及斜裂缝宽度进行了对比分析。试验结果表明,此类构件的受力性能与普通钢筋混凝土受剪构件相同,其斜截面受剪承载力仍可按现行《混凝土结构设计规范》有关公式进行计算,并且具有足够的安全储备。同时蒙皮钢筋的配置能够有效地限制裂缝的开展,改善受剪破坏的脆性性能。

The shear behavior and diagonal crack width at service stage are discussed and analyzed according to the tests of 8 concrete beams with 500 MPa steel bars as stirrup under concentrated load. And two groups of members with welded wire fabric near the concrete surface are designed and compared for shear capacity and diagonal crack width. The test results indicate that concrete beams with 500 MPa steel bars as stirrup show similar behaviour to the beams with conventional stirrup and the formula in code for design of concrete structures can be used to calculate its shear capacity which have enough safety. Furthermore, the welded wire fabric can not only be used to control diagonal crack but also improve the brittle performance of shear failure.