Pullout behavior of perforated steel plate connections with UHPC

Abstract

This paper presents an innovative non-contact lap splice connection system for integrating double-steel-plate composite (DSPC) walls with reinforced concrete (RC) structures. This system employs ultra-high performance concrete (UHPC) and perforated steel plates to reduce the bar-to-plate lap splice length and simplify construction procedures. To evaluate the pull-out behavior of the perforated steel plate connections with UHPC, 21 specimens were designed and fabricated for monotonic tensile testing. Key test parameters included the perforated plate spacing, number of holes, and hole diameter. The primary failure modes were concrete overall pull-out failure and rebar fracture. For concrete pull-out failure, the load-slip curve displayed three distinct phases: elastic phase, plastic development phase, and descending phase. Specimens with perforated plates demonstrated higher elastic limit loads than non-perforated counterparts, and the peak-to-elastic-limit load ratios range from 1.24 to 1.40. During the descending phase, the load decreased linearly with increasing slip. The peak load increased proportionally with the number and diameter of holes, while perforated plate spacing showed negligible influence on the peak load. Both the peak load and shear stiffness exhibit a strong linear correlation with the area of the UHPC dowels. Based on the test results, design formulae for predicting the shear capacity of the novel perforated plate connections were proposed.