Effects of Embedment Length and Spacing on Capacity of Post-Installed Rebars

• Main Authors: Hong-Yu Pan, 潘宏育
• Other Authors: Chi-Ping Wang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/35914600560253532930

碩士 === 逢甲大學 === 土木工程所 === 99 === Rebar setting technique is commonly used in concrete construction when there is a need of alteration, extension or reinforcement of structures. In order to ensure the safety of rebar setting, reasonable design specifications and construction standards have been the practical requirements. However, formal design or construction standards of rebar setting are currently unavailable, and researches focused on failure behavior and ultimate capacity of post-installed rebars are relatively limited in number. Therefore, the main objective of this study is to investigate the influence of epoxy resin mortar, embedment length, rebar spacing, edge distance and other factors on both tensile and shear capacity of post-installed rebars by means of experimental tests. This study also compare the experimental results with the predicted values calculated based on the design formula suggested by two manufacturer’s technical manuals. The experimental results showed that both epoxy resin mortars used in this study could provide excellent adhesive effect. The post-installed rebars performed much better in the pull-out tests than the pre-cast rebars. The effect of embedment length on the tensile capacity was more obvious than that of rebar spacing, while larger rebar spacing and edge distance significantly improved the shear capacity of rebar system. In both tensile and shear tests, specimens failed due to steel fracture showed higher strength than the specimens displayed concrete failure. However, there are many types of concrete failure, it is difficult to correlate the rebar tensile or shear capacity with the concrete failure types. Besides, the capacity of rebar system calculated by two manufacturers’ design procedures were quite different. Moreover, the calculated shear capacity were much higher than the experimental values. Therefore, we have to be cautious and conservative while using the formula to estimate capacity of the rebars.