Impact resistance of gypsum board subjected to low velocity impact

Abstract

Original scientific paper The aim of this study was to investigate the impact resistance and damage behaviour of gypsum and composite gypsum boards subjected to low velocity impact. Low velocity impact tests were performed on four different board materials which can be listed as gypsum boards, gypsum+75 gr/m² mesh boards, gypsum+wallpaper boards and gypsum+75 gr/m² mesh+wallpaper boards. Indenter used in the impact tests was 24 mm in diameter and has semi spherical tip geometry. Gypsum and composite gypsum boards were bonded in 500×400 mm sizes and simply supported at four sides. Various energy levels, i.e. 2, 4, 6, 8, 10 and 12 J were applied to the centre of each board. As a result of low speed impact tests, impact force-time and force-displacement variations were obtained and the damaged regions of the samples were examined. Penetration thresholds and perforation thresholds of gypsum and composite gypsum board samples were determined by using Energy Profile Method (EPM). The effect of adding mesh and wallpaper into the gypsum board on stab and puncture limits was evaluated. Around 62.40 % increase occurred on gypsum+mesh+wallpaper board comparing to gypsum board in perforation thresholds. Keywords: EPM method; impact resistance; gypsum board; low velocity impact Otpornost na udar gipsane ploče izložene udaru male brzineIzvorni znanstveni članka Cilj ovoga rada je istražiti otpornost na udar i ponašanje kod oštećenja gipsanih i složenih gipsanih ploča izloženih udaru male brzine. Ispitivanja udara male brzine provedenu su na četiri različita materijala ploča, i to gipsane ploče, gips+75 gr/m² mrežaste ploče, ploče od gipsa+zidna tapeta i ploče od gipsa+75 gr/m² mreže+tapeta. Udubljenje korišteno u udarnim ispitivanjima bilo je 24 mm u promjeru i geometrije polu kuglastog tipa. Gipsane i složene gipsane ploče bile su spojene u veličinama od 500×400 mm i jednostavno pridržavane na četiri strane. Na sredinu svake ploče djelovalo se energijom različitih razina: 2, 4, 6, 8, 10 i 12 J. Kao rezultat ispitivanja udara male brzine, dobivene su varijacije udarna sila-vrijeme i sila-pomak te su ispitivana oštećena područja uzoraka. Granice penetracije i granice perforacije uzoraka gipsanih i složenih gipsanih ploča određene su EPM metodom (Energy Profile Method). Procijenio se učinak dodavanja mreže i tapete u gipsanu ploču na granice izdržljivosti kod udaranja i probijanja. Na ploči od gipsa+mreža+tapeta došlo je do porasta granice perforacije od oko 62.40 % u usporedbi s gipsanom pločom.