Model Test of Shear Strengthened Prefabricated Voided Slab Bridge
-
摘要: 针对传统加固方法受空心板桥作业空间的限制，难以实现空心板桥抗剪加固的这一弊端，提出一种凿除空心板端部顶板并在端部空腔内注入混凝土的空心板桥抗剪加固方法。模型试验结果表明，未加固的空心板在试验荷载作用下，腹板发生开裂后试验构件立即失去承载能力。加固后的空心板在腹板发生开裂后可以继续保持承载，填芯混凝土与空心板混凝土保持整体受力。加固后空心板腹板发生开裂时的荷载较未加固的空心板提高5.1%,极限荷载较未加固的空心板提高19.2%。加固后的加载点的挠度比加固前小21.1%,而加固后跨中截面的挠度比加固前小4.0%。加固后空心板最大剪应变比加固前降低约7%。说明抗剪加固可以有效提高空心板抗剪承载能力，空心板端部填充的混凝土极大地提高了支点附近的局部刚度。Abstract: Aiming at the disadvantage that the traditional strengthening method is limited by the working space of the voided slab bridge, which is difficult to strengthen the shear performance of the bridge, a voided slab shear strengthening method that removes the top plate and inject grouting concrete in the end of the slab is proposed. The model test results show that, for the voided slab without strengthening, the slab loses the shear bearing capacity immediately when the web plate cracks emerged under the test load. For the strengthened voided slab, it can remain bearing the load after the web plate cracks, and the grouting concrete and the voided slab maintain suffering as a whole. For the strengthened slab, the load when the web plate cracks emerged is 5.1% higher than the unstrengthened slab, while the ultimate load is 19.2% higher than that of the unstrengthened slab. The deflection of the loading point after strengthening is 21.1% smaller than the unstrengthened one, and the deflection of the mid-span section after strengthening is 4.0% smaller than the unstrengthened one. The maximum shear strain of the slab after strengthening is about 7% lower than the unstrengthened one. The shear strengthening can effectively improve the shear bearing capacity of the slab. The grouting concrete at the end of the slab significantly improves the local stiffness near the end.
-
-
[1] 吴庆雄,黄宛昆,陈宝春,等.结合面底部设开孔钢板的铰接空心板力学性能[J].交通运输工程学报,2017,17(4):45-54. [2] 张劲泉,李鹏飞,董振华,等.服役公路桥梁可靠性评估的若干问题探究[J].土木工程学报,2019,52(S1):159-173. [3] 袁伟璋,黄海云,张俊平,等.基于实际运营车辆荷载效应的既有桥梁可靠度研究[J].振动与冲击,2019,38(6):239-244. [4] 周术明,颜东煌.车辆荷载作用下损伤开裂简支空心板的断裂力学特征[J].公路交通科技,2019,36(1):94-101. [5] Hussein H H,Sargand S M,Khoury I,et al.Environment-induced behavior of transverse tie bars in adjacent prestressed box-girder bridges with partial depth shear keys[J].Journal of Performance of Constructed Facilities,2017,31(5):1-13.
[6] 张劲泉,李鹏飞,韦韩,等.注浆加固预应力混凝土空心板梁抗剪性能试验研究[J].工程力学,2020,37(S1):32-41. [7] 赵亚飞,周建庭,宁金成,等.体外预应力加固钢筋混凝土空心板的试验研究[J].重庆交通大学学报(自然科学版),2012,31(1):22-24,28. [8] Hussein H H,Walsh K K,Sargand S M,et al.Interfacial properties of ultrahigh-performance concrete and high-strength concrete bridge connections[J].Journal of Material Civil Engineering,2016,28(5):04015208.
[9] 宗周红,程怡,黄学漾,等.CFRP板加固RC&PPC梁抗剪性能试验研究[J].工程力学,2013,30(6):236-246. [10] Chen Guangming,Teng J G,Chen Jianfei.Shear strength model for FRP-strengthened RC beams with adverse FRP-Steel interaction[J].Journal of Composites for Construction,2013,17(1):50-66.
[11] 王渠,吴庆雄,黄宛昆,等.预应力碳纤维板加固空心板桥试验研究[J].南昌大学学报(工科版),2019,41(3):247-252. [12] Escrig C,Gil L,Bernat M E,et al.Experimental and analytical study of reinforced concrete beams shear strengthened with different types of textile-reinforced mortar [J].Construction & Building Materials,2015,83:248-260.
[13] Liu Simeng,Sun Ma,Liu Qing.Study on bearing capacity of beams strengthened with section enlargement method considering secondary loading process [J].Advanced Materials Research,2012,368:2200-2203.
[14] 杨斌,陈世宏.增大截面加固受弯构件的斜截面抗剪承载力计算方法[J].公路交通科技,2016,33(8):99-105. [15] 项贻强,邢骋,邵林海,等.横向加固空心板梁桥荷载横向分布计算方法与试验研究[J].中国公路学报,2013,26(2):63-68. [16] 聂建国,蔡奇,张天申,等.高强不锈钢绞线网-渗透性聚合砂浆抗剪加固的试验研究[J].建筑结构学报,2005,26(2):10-17. [17] 顾冠男.预应力空心板梁抗剪试验及注浆加固方法研究[D].南京:东南大学,2021. [18] 公路桥梁加固设计规范:JTG/T J22—2008[S].北京:人民交通出版社,2008. [19] 混凝土结构加固设计规范:GB 50367—2013[S].北京:中国建筑工业出版社,2013. [20] 公路钢筋混凝土及预应力混凝土桥涵设计规范:JTG 3362—2018[S].北京:人民交通出版社,2018.
计量
- 文章访问数: 0
- HTML全文浏览量: 0
- PDF下载量: 0
下载:
