Experimental study on stable bearing capacity of wheel-buckle formwork support frames

Abstract

To prevent the frequent jamming of straight plugs and disk plates, a novel wheel-buckle joint was introduced and investigated in this study. The destabilization failure mode and stable bearing capacity of the new wheel-buckle formwork support frame were studied through nine full-scale test models. Different influencing factors such as the horizontal scissor brace, vertical scissor brace, spacing of the standing tube, and lift height were considered in these tests. The results indicate that all the models tended to adopt a non-sway buckling mode with a large wave valley, and that the maximum horizontal displacement occurred in the upper-middle part of each model. The stable bearing capacity of each model increased with a decrease in the lift height and spacing of the standing tube. Furthermore, the arrangement of vertical scissor braces could significantly improve the stable bearing capacity of the models. Based on the stability theory, a simplified calculation formula for the stable bearing capacity of the support frame was established. The values calculated through the simplified formula were compared with the values calculated through the JGJ300-2013 code and the test values. It was observed that the formula has sufficient accuracy (average error 13.4 %) in predicting the stable bearing capacity of the support frame, and that the JGJ300-2013 code has sufficient bearing capacity reserve. Notably, the conclusions of this study can serve as a reference for further research on new wheel-buckle formwork support frames.