The current housing shortage problem in the country, especially among the low-income group and the necessity to address their shelter needs, led to the introduction of GFRG (Glass Fibre Reinforced Gypsum) panels in India. GFRG panels can be used as infills in multi-storeyed framed construction, and the lateral load behaviour of GFRG infilled RC (reinforced concrete) frames is strongly influenced by the filling inside the cavities of the panel. A quasi-static cyclic lateral load test was performed on GFRG infilled RC frames with the cavities of the panel filled with M 20 concrete (specimen C), quarry dust and 5% cement mix (specimen Q) and without any filling (specimen D), to understand their behaviour. It is established that the failure of the specimen under lateral load is characterised by the failure of the infill wall, with excessive crack formation before the yielding of the frame members. The test results showed the contribution of GFRG panel to the strength, stiffness and other performance parameters of a RC frame.
When the cavities of the panel are left unfilled, the connection between the GFRG panel and the RC frame is established using cold-formed steel (CFS) sections with suitable screw connections, and this screw connection, which experiences shear, dictates the behaviour in such cases. Therefore, the behaviour and strength of the screw connection between CFS profiles and the GFRG panel was studied by conducting monotonic and cyclic shear load tests. The results demonstrated the influence of CFS plate thickness, screw diameter, edge distance of the screws and placement of the CFS plate on various performance parameters of CFS-GFRG screw connection.
The monotonic lateral load-deflection behaviour and the in-plane hysteresis response of the GFRG infilled RC frames was then simulated by performing monotonic and cyclic pushover analysis in SAP2000NL, by incorporating pivot hysteretic models for the materials, hinges and links. The reliability of the proposed numerical model was then validated by comparing the numerical modelling results with the experimental results and it was found that the proposed numerical model was able to capture the monotonic and cyclic load-deflection behaviour, with sufficient accuracy.