Bond Strength of Bar Connector Performance in Male-Female Interlocking Panel (M-FiP)

Abstract

In this paper, the bond strength characteristic between reinforcement bar and cement grout as a wet joint connection mechanism in male-female interlocking panel (M-FiP) was investigated. The bond strength result depended on cement grout strength respectively. Total eight (8) specimens were constructed with grout strength as variables. Recycled aggregate with size 10 and 20 mm has been used as replacement normal aggregate in concrete production Grade 30 of male and female panel. The 12 Ø reinforcement bar size was used and installed vertically for all M-FiP specimens. The test result demonstrated that the average bond strength for all different days with cement grout strength about 58.70, 64.50, 64.70, and 90.60 N/mm2 is 3.80, 3.93, 3.99, and 4.29 N/mm2, respectively. From this result, it can be seen that the bond strength was influenced by material strength that has been used surrounding the reinforcement bar. The percentage increment of bond strength in different cement grout strength is 3.4, 5, and 12.9 % when compared with bond strength for 7 day M-FiP specimens. The high strength of cement grout provided greater bearing resistance against slippage between cement grout key and steel reinforcement bar. In fact, longer development length embedded in cement grout added the numbers of key that resist the slippage and directly increased the bond strength. The pullout failure occurred to all M-FiP specimens when concrete sur- rounding steel reinforcement bar ribs or called as concrete key is weak and other concrete at surrounding steel reinforcement bar is strong.