Bond Characteristics of Deformed Steel Rebar in Palm Kernel Shell (PKS)-Rubberised Concrete Composite

Abstract

The bond mechanism between concrete and steel is an important input parameter in the design of reinforced concrete elements. The reuse of waste materials as aggregates in concrete has led to the discovery of different types of concrete with unique bond characteristics. This paper reports on the bond characteristics of concrete produced from waste automobile tire chips and palm kernel shell aggregates and deformed mild steel rebars. A total of 125 concrete cubes (150 x 150 x 150mm) with metal inserts were cast from 21 concrete mixes with varied content of PKS and waste automobile tire aggregates. Pullout test was carried out to evaluate the strength of the bond mechanism between the steel and the various concrete mixes. The results revealed that bond strength decreased with increasing PKS and tire content. Moreover, increasing the bar size and embedment length reduced the bond stress. The ratio of the bond stress and compressive strength was found to be averagely 63.88%. Regarding the bond failure mechanism, it was identified that failure of the specimen occurred through either rebar pullout or tensile splitting of the concrete. Based on the results obtained, it was concluded that PKS and tire can be used as partial replacement of granite aggregates in concrete since the resultant concrete can develop adequate bond with steel bars in structural applications.

Anchorage Bond Strength of Glass Fibre Polymer Reinforced Concrete with Palm Kernel Shells as Partial Coarse Aggregate

“…9. Increase in bond strength with decreasing embedment lengths were also observed by previous studies [16][17][18][19][20] and can be attributed to the gradual transfer of the bond stress during the pull-out test from the loaded end to the free end which results in a nonlinear stress distribution of the bond stress along the embedment length [18][19][20]. Conversely, the specimens with 300mm (continuous) embedment recorded the highest average anchorage bond strength values of 6.174N/mm 2…”

“…More recent study by Boateng et al [16] looked at the bond characteristics of concrete produced from PKS-waste automobile tire aggregates and embedded with deformed mild steel reinforcing bars. Concrete cubes (150mm x 150mm x 150mm) were cast with varying PKS-tire content of 0%, 25%, 50% 75% and 100% and with steel bars of embedment lengths 75mm and 150mm.…”

Experimental Investigation into Strength Properties of Ribbed Mild Steel Reinforcing Bars (RMSRBs) Produced by Local Companies in Ghana

“…The choice of steel bars is based on strength, cost, accessibility, ease of erection, aesthetics, sustainability, and other environmental concerns (Ede et al, 2015). The performance of reinforced concrete as structural material depends strongly on the properties of the steel bars and concrete (Boateng et al 2023). The ribbed steel bars have the advantage of increasing the bond strength at the concrete steel interface to improve the tensile and compressive properties of the reinforced concrete.…”