Study on Concrete Filled Joints with Bolted Connections

My book focuses on the experimental and analytical study of cold-formed tubular steel sections, particularly at their bolted joints, to improve structural performance and reliability. Cold-formed sections are increasingly used in construction, transportation, agriculture, and mechanical industries due to their lightweight and versatile nature, but their bolted connections often fail by tearing, bearing, or torsional buckling because of thin cross-sections. This work explores a novel approach of infilling these tubular sections at the joints with either conventional concrete or geopolymer concrete to enhance load-carrying capacity and delay failure. Through a series of controlled laboratory experiments on single-bolted tubular tension members, the study investigates the strength, elongation, and strain behavior of the connections. MATLAB-based polynomial modeling is further used to predict maximum load capacities across varying thicknesses. The book highlights the comparative performance of conventional versus geopolymer concrete, demonstrating that both materials can improve joint strength, with geopolymer offering additional environmental benefits.