Deflection function of a novel bolt-connected precast concrete floor

Abstract

Owing to the post-cast procedure and relatively complex joint configuration, composite precast floors limit the full display of advantages of precast concrete systems. The development of fully assembled precast floors is of necessity; therefore, a novel bolt-connected precast concrete floor was proposed in this study to meet the increasing demand for quick assembly, lightweight, and good insulation in flooring systems. The proposed floors consist of precast sandwich unit slabs that are fully assembled to an integral floor with dry-type bolted connectors. Field static loading tests were conducted on four full-scale precast concrete floors. The test results indicate that the floors exhibited a two-way flexural ability due to the involvement of the bolted connectors. The restraining mechanism at anchorage and load-transferring mechanism at joints were investigated through a theoretical analysis. Based on the theory of plates and shells, a simplified theoretical method of solving the deflection function of the floors was established and validated to provide a reference for designing such fully assembled floors. The comparison between the theoretical and experimental results indicates that the arrangement of joint connectors could affect the theoretical calculation accuracy due to its influence on the performed continuity simplification. The application scope of the proposed theoretical method was evaluated through a finite element analysis.