Behavior of Steel-Concrete-Sandwiched Beam with Steel Fiber Reinforced Concrete Core and X-Form Shear Connectors

摘要

Steel-concrete-sandwich (S-C-S) construction has its applications in protection against fatigue, impact and blast loads. In blast-resistant construction, concrete is the most predominantly used building material. Due to the impact of blast loads, the structural and material integrity of concrete gets deteriorated due to spalling, cracking, etc. Recent studies have showed that steel-concrete-sandwich structures exhibited better ductility, structural integrity and blast-resistant capacity. The paper presents a numerical study on steel-concrete-sandwiched beam with through-through shear connectors (S-C-S-TT) after validation from previous experimental tests. Also, the shear connector of the S-C-S-TT beam was modified to X-form shear connectors (S-C-S-X) and its behavior due to the configuration change was studied. The performance of the S-C-S-X beam was found to be superior in terms load carrying capacity and deflection capacity than the S-C-S-TT beam. In order to understand the role of fiber reinforced concrete in S-C-S construction, a new S-C-S-X beam with steel fiber reinforced concrete core (S-C-S-X-SFRC) was modeled and its performance was comparatively studied with S-C-S-TT beam and S-C-S-X beam. The results showed that the S-C-S-X-SFRC beam exhibited enhanced deflection capacity as well as high load carrying capacity than S-C-S-TT beam and S-C-S-X beam. A parametric study was carried out by varying the diameter of connectors, thickness of cover plates and spacing of connectors of S-C-S-X-SFRC beam. From the study, the deflection capacity, which is considered as an important factor for absorbing energy and for designing structures against explosion induced forces, of S-C-S-X-SFRC was found to be high, and thus, it can be used as an alternative to conventional concrete in areas subjected to extreme loading.