Pull-out Shear Strength of Planar Reinforced Concrete Members

平面钢筋混凝土构件的拉拔剪切强度

基本信息

批准号：
63550345
负责人：
KAKUTA Yoshio
金额：
$ 1.47万
依托单位：
Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1989
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63550345/
关键词：
Reinforced Concrete Slab Footing Punching Shear Pull-out Shear Shear フーチング

项目摘要

A mechanism of failure of reinforced concrete members subjected to pull-out forces is extremely complicated and there are many problems to be made clear. It is known that the punching shear strength decreases as a loading position approaches the free edge of a member, however, the test data concerning such behavior are not enough to be applied to the design of various kinds of members. Furthermore, the effectiveness of shear reinforcement in the case of short shear span still remains uncertain.In this study reinforced concrete slab and deep beam specimens were tested. The variables investigated in the slab tests were distance from load to free edge, depth of loading position ( surface loading and embedded loading), arrangement of main and distribution reinforcements, slab width and presence of stirrups, and those in the deep beam tests were shear span-to-depth ratio, type of shear reinforcement stirrups, horizontal bars, combined stirrups and horizontal bars ) and amount of shear reinforcement.The principal results obtained are as follows; 1) In the design of planar members subjected to pull-out forces it is convenient to classify into five types of failure mechanism; beam shear with full width, beam shear with effective width, punching shear with full length of critical section, punching shear with effective length of critical section and shear of plain concrete. 2) The effect of stirrups in the case of short shear span may be less than the value estimated by the truss theory. Reduction factor as a function of shear span ratio and degree of shear reinforcement may be introduced.

受到拔出力的钢筋混凝土成员失败的机制非常复杂，有很多问题要明确。众所周知，随着载荷位置接近成员的自由边缘，冲压剪切强度会降低，但是，有关此类行为的测试数据不足以应用于各种成员的设计。此外，在短剪切跨度的情况下，剪切钢筋的有效性仍然不确定。在这项研究中，测试了这项研究加强混凝土板和深束样品。在平板测试中研究的变量是从载荷到自由边缘的距离，负载位置的深度（表面载荷和嵌入式负载），主和分布增强的排列，平板宽度和stir stirups的存在，以及深束测试中的均方根跨度与深度比例，剪切钢筋马stir，水平棒，组合搅拌棒和水平条）以及剪切加固的量。所获得的主要结果如下； 1）在受到拉出力的平面成员的设计时，将分类为五种类型的故障机制很方便；横梁具有全宽，梁剪切，具有有效宽度的横梁剪切，用临界截面的全长打孔剪切，用有效的临界截面和普通混凝土的剪切剪切。 2）在短剪切跨度的情况下，马stir的作用可能小于桁架理论估计的值。可以引入还原因子作为剪切跨度比和剪切钢筋程度的函数。