SHEAR BEHAVIOR OF FULL-SCALE POST-TENSIONED PRESTRESSED CONCRETE BRIDGE GIRDERS
SHEAR BEHAVIOR OF FULL-SCALE POST-TENSIONED PRESTRESSED CONCRETE BRIDGE GIRDERS
复制标题
全尺寸后张预应力混凝土桥梁大梁的剪切性能
DOI：
10.14359/13014
复制
发表时间：
2004
影响因子：
1.8
通讯作者：
Kwang Soo Kim
中科院分区：
文献类型：
--
作者：
B. Oh;Kwang Soo Kim
足尺后张预应力混凝土梁（PPCGs）的抗剪性能的试验数据非常有限。因此，本研究旨在探讨PPCGs的剪切性能。大型PPCG的设计，制造和测试1.2米深× 10.6米长的PPCG与中高和高强度混凝土。梁进行了测试失败，而挠度，钢应变，开裂模式，和平均应变在腹板进行了监测。应变在开裂后立即突然增加，并随着载荷的增加而继续增长。为了测量3个方向的平均应变，线性可变差分传感器（LVDT）的三角形网格也被放置在梁的剪切区域。这些LVDT即使在发生对角裂纹后也能测量垂直、纵向和对角方向的平均应变。从这些测量的平均应变计算剪切应变、主应变和主方向。结果表明，主应变方向角随载荷的增加而减小，在极限载荷下，主应变方向角约为23-25 °。
Test data on shear behavior of full-scale posttensioned prestressed concrete girders (PPCGs) is very limited. Therefore, this study aimed to experimentally explore the shear behavior of PPCGs. Large-scale PPCGs were designed, fabricated, and tested on 1.2 m deep x 10.6 m long PPCGs with medium-high and high-strength concretes. The girders were tested to failure while deflections, steel stirrup strains, cracking pattern, and average strains in the web were monitored. The stirrup strains showed a sudden increase immediately after cracking and continue to grow as the load increases. To measure the average strains in 3 directions, triangular grids of linear variable differential transducers (LVDTs) were also placed at the shear regions of the girders. These LVDTs enable measurement of average strains in the vertical, longitudinal, and diagonal directions even after the diagonal cracking has occurred. Shear strains, principal strains, and principal directions were calculated from these measured average strains. It was found that the angle of principal strain direction decreases as the applied load increases and that it approaches ~23-25 deg at ultimate load.