Behaviour of Structurally Insulated Panels

Abstract

The transition from conventional practices, such as traditional brick masonry, to contemporary construction methods like concrete sandwich panels is gaining notable traction. This shift not only reflects a growing trend but also signifies a substantial movement towards more advanced and efficient construction techniques in the modern era. The primary aim of the study is to examine the behaviour of concrete sandwich panels reinforced with geosynthetics in terms of out-of-plane, in-plane shear, and compression. Two forms of geosynthetic material are being utilised, specifically plastic uniaxial geogrid (PUG) and polyester biaxial Geogrid (PBG). Two types of mixes have been used to further enhance the understandability of the behaviour of concrete sandwich panels The flexural behaviour of concrete sandwich panels strengthened with geosynthetics is examined in first phase of this study. The panels are tested under a monotonically increasing load using a hydraulic jack. The load–deflection curves of the panels were examined to evaluate the effect of geosynthetics on the strength, stiffness, and deformability of panels. The result shows that plastic geogrid reinforced sandwich panels enhanced the flexural strength and ductility of panels compared with control specimens. Polyester geo-grid as reinforcement is also found to be relatively better in restoring the deformability and energy absorption of panels. The results show a gain of about 28% in plastic geogrid (SPGG); 36.8% in the case of polyester geogrid (SGi200), in comparison with the control specimen. In-plane diagonal shear strength of concrete sandwich panels, and the effect of incorporating geogrids on the deformation capability and load-bearing capacity is also reported in the study. In contrast to the control specimen, specimens cast with plastic geogrid had a 13.7% and 26% improvement in shear capacity and load-bearing capability for the two types of micro-concrete mixes used in this study. Diagonal shear specimen containing PUG is effective in improving the concrete sandwich panels’ load-bearing capacity, shear capacity, and deformation ability. PBG enhanced the ductility of the concrete sandwich panels. Axial compression testing of these concrete sandwiched panels supported the above mentioned parameters as PUG containing specimen outperformed the control specimen. On the3 other hand the specimen containing PBG enhanced the deformation capacity of the concrete sandwich panel .the results are supported by the energy dissipation values computed from the area under the curve in the load vs deformation graph. In second phase of the study two dimensional reinforced concrete frames has been cast using CSP as infill wall and compared with brick masonry as infill wall. Three single bay and single story RC frame specimens were tested under reversed cyclic lateral loading. It has been found that addition of sandwich panels led to a considerable increase in the lateral stiffness and strength, ductility, energy dissipation capacity. The 2D RC frame with concrete sandwich panel as an infill wall exhibits greater ductility compared to the brick masonry. The increase in lateral load capacity can be attributed to the enhanced rigidity of the concrete sandwich panel. Furthermore, the calculation of energy dissipation is consistent with the values derived from the hysteresis curve. A comparison is made between a 2D reinforced concrete (RC) frame with a concrete sandwich panel that has a door opening, and a 2D RC frame with a complete concrete sandwich panel infill wall subjected to lateral load. Upon comparing it with the other 2D RC CSP frame, it was seen that the opening resulted in significant deformations of the CSP. The flexure, diagonal shear and axial compression specimen have been subjected to numerical simulation using CAD software to create the geometry and ANSYS Workbench, a FEM software, to analyse it. The simulation results are highly consistent with the experimental findings.