镂空套筒灌浆接头形式试验研究

Experimental Study on the Grouted Splice Using a Type of Opening Sleeve

针对目前灌浆套筒形式复杂、加工成本高、内腔结构不利于灌浆密实、浆料密实度检测困难等问题,设计了一种球墨铸铁一次铸造成型的镂空套筒。以16mm直径钢筋为例,开展了灌浆套筒接头的单向拉伸试验。结果表明,套筒内径减小能有效提高钢筋的锚固强度,环肋数量增加也能提高钢筋锚固强度但效果不明显;对于1/2套筒长度内有3道肋的内径31mm的镂空套筒,当钢筋锚固长度为170mm,即套筒长度为350mm时,其接头试件单向拉伸试验满足规范要求。

At present,most of the grouted sleeves are complex shaped,high processing cost and difficult to test the grouting density,and the complex inner cavity structure is not conducive to grout as well.In view of the above problems,a type of opening sleeve which can be cast by nodular cast iron was designed.Taking 16 mm diameter steel bars as example,the uniaxial tensile test of several groups of grouted sleeve splice was carried out.The experimental results show that the reduction of the inner diameter of the sleeve can effectively improve the anchorage strength of the bar,and the increase of the number of ring ribs can also improve the anchorage strength of the bar,but the effect is relatively less obvious.For the new window sleeve whose inner diameter is 31 mm with 3 ribs in the length of the 1/2 sleeve,when the anchorage length of the bar is 170 mm,that is,the length of the sleeve is 350 mm,the results of the direct pullout test can meet the requirements in the standard.