Reserch on The Bond Strength between Concrete and Anchor

• Main Authors: Hong-Ru Xie, 謝泓儒
• Other Authors: 黃中和
• Format: Others
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/v94p35

碩士 === 國立臺北科技大學 === 土木工程系土木與防災碩士班 === 104 === This study investigated the differert types of expansion anchors in concrete to be applied pullout force solely with experiment. Materials considered variables contained anchor type、anchor size、the strength of concrete、cracked width and depth of concrete(see ACI 355 standard manufacture artificial cracked concrete), also investigated the effect of installed on the anchor pullout strength, hope the study can grasp anchor ability. At the same time, the test results with the strength design specification values were compared to assess the suitability of the design value of the anchor. The experiment results indicated the less distance between the cast-in-place hooked anchor or improperly lock on steel, the anchor pullout load will reduced. Different types of expansion anchor have different anchor ability on concrete, H-type grip anchors have maximum pullout load, the worst type of Sleeve expansion anchors. When the crack width increased from 0.14 mm to 1.00 mm, the average anchor pullout load reducted about 12%, and the crack depth increased from 5 mm to 40 mm, the average anchor pullout load reducted about 20%. In terms of construction error anchors,when the post-installed anchor had too shallow and too deep depth in concrete,the anchors cant expand well in concrete and the anchor pullout load reduced, anchor failure mode will change to anchor pull-out, especially when no expansion anchor were applied pullout force solely, its anchor pullout load will decrease 92%. ACI specifications for strength design of anchors, Sleeve expansion anchors safety factors were less than 1, and when the anchor in the cracked concrete, the specifications did not consider the effect of the crack widths and depths to the anchor pullout strength , so that the design value were not conservative.