自密实混凝土与老混凝土粘结抗剪性能试验研究

Experimental reserch on shear properties of selt-compating concrete on existing concrete

对9组27个山形试件的自密实混凝土与老混凝土粘结面进行抗剪试验,考察刻槽密度、粘结面积、植筋对自密实混凝土与老混凝土粘结面抗剪强度的影响.试验结果表明,粘结面的不同处理方法对其抗剪强度影响较大,增大刻槽密度效果远好于增加新老混凝土的粘结面积,植入抗剪钢筋效果不如增大刻槽密度明显.通过试验分析,得出自密实新混凝土与老混凝土粘结抗剪强度计算式,为实际加固工程提供参考.

Shear experiments were conducted on 27 ＂山＂ - shapes pecimens from 9 different groups to investigate the shear properties of the interface of self - compacting concrete （SCC） and old concrete. Based on the test, the effects of specific factors on adhesive shear performance are investigated. These factors are as follows： groove density, bonded area, reinforced bar planting. The results show that the interfacial techniques have a great effect on the shear properties of a new - to - old concrete interface.. The shear strength of specimens is greatest when the technique of groove density is used in the three interfacial techniques. Furthermore, reinforcing steel bar planting can improve the shear properties of the interface remarkably. Based on the test result, an expression of shear strength of self compacting concrete on existing concrete is presented for the reference to the strengthening of concrete structure.