砌体结构在屋面拉线塔拉拔作用下的试验研究

关键字：砌体结构,拉拔,极限荷载,破坏模式

（1.河南省信息咨询设计研究有限公司，河南 郑州  450008；2.郑州科技学院，河南 郑州  450064）

    摘要：屋面拉线塔作为一种常见的天支形式，在通信基站中应用十分广泛，拉线一般锚固于砌体结构的女儿墙中，锚点的锚固稳定性对于屋面拉线塔来说至关重要。砌体结构是由强度较低的砖块和砂浆粘结而成，对于拉线荷载下结构的破坏形式尚没有明确的认识，创造性的利用支撑架装置对墙体施加拉拔力，对墙体结构不施加反力，使实验结果更接近实际受力；通过对不同墙体高度，不同砂浆和砖块强度的试验，提出砌体结构的主要破坏模式是底部的水平剪切破坏，中部V型裂缝的剪压破坏，墙体端部的弯曲拉裂和扭转拉裂破坏。并基于试验数据提出了极限拉拔力在统计上的计算公式，对拉线塔锚固点的设计计算具有一定的参考价值。
    关键词：砌体结构；拉拔；极限荷载；破坏模式
    中图分类号：TU37          文献标识码：A          文章编号：1001-702X（2017）06-0058-05

Experimental research on masonry structures under the drawing action of roof pulling tower
ZHENG Longxin1，FAN Liujun2，MIAO Peng2
（1.Henan Information Consulting Design and Research Limited Company，Zhengzhou 450064，China；
2.Zhengzhou Institute of Science and Technology，Zhengzhou 450008，China）

    Abstract：Roof pulling towers are widely used in communications base stations because they are commonly used in towers. They are anchored in the masonry structure of the parapet. Anchoring stability of anchors for the roofing towers is important. The masonry structure is made of low-strength bricks and mortar，and there is no clear understanding about the failure mode of the structure under the tension load. This paper creatively utilizes the supporting frame device to exert the pulling force on the wall without counter-force to make the test result closer to the actual force. Through the test on different wall height，mortar and brick strength，the results proposed that the main failure mode of the masonry structure is the horizontal shear failure at the bottom，the shear failure mode of middle V-shape cracks，bending cracking at the end of the wall，and torsion cracking damage. Based on the experimental data，the formula for calculating the ultimate pullout force is put forward，which has certain reference value for the design and calculation of anchorage points of towers.
    Key words：masonry structure，pullout，ultimate load，failure mode