Experimental Studies On Shear Behavior Of Adhesive Anchor And Post-Installed Rebar

Anchoring technology is divided into embedded anchoring and post anchoring.The mechanical anchor bolt and the adhesive anchor bolt are also used in the post anchor technology.The anchoring mechanism of adhesive anchor bolt and post-installed rebar is basically the same,which is the post-anchoring technology that fastens anchor bar to concrete base material through structural anchoring glue and effectively connects existed structure and new structure with chemical binding.Based on the analysis and comparison of domestic and foreign research results on shear calculation method and influence factors of connecting anchor bars,the shear performance of embedded parts,post-installed rebar and adhesive anchors was studied under the condition of single anchor and group anchor.The specific contents include:There were 30 specimens in single anchor shearing test.Mainly focused on the shear load-displacement curve and the bearing capacity,as well as displacement of embedded parts(buried in concrete and placed on the concrete,post-installed rebar(fixed with nut and welding)and adhesive anchor bolt.The study showed that shear bearing capacity of post-installed rebar were between embedded parts and the adhesive anchor.Based on the test results,a formula for calculating the shear capacity of three kinds of anchoring bars was proposed.In addition,the corresponding finite element model was established and compared for single anchor test.There were 20 specimens in group anchors.The research content was similar to single anchors.In addition,based on the results of single anchors' bearing capacity,the shear capacity coefficient of four anchor bars in group anchors was calculated.The results show that the shear strength coefficient of post-installed rebar is the largest,followed by adhesive anchors and the embedded parts were the smallest.It is mainly caused by different stiffness and different ductility of the material.In order to explore the applicability of the formula of embedded parts in China,8 single anchor specimens with diameter of 28 mm were made for shear test.The results showed that the formula of shear capacity of embedded parts was conservative in China.Whether this formula can be applied to the post-installed bar needs further discussion and may not be applicable to the calculation of chemical anchoring bolt.