Headform Kompostt Polimer dan Responnya Akibat Beban Impak Kecepatan Tinggi

Abstract

This theses reports results of experimental and numerical study of human head model (headform) and brain model used for industrial safety helmets. The headform produced is made from glass fiber reinforced plastic (GFRP) polymeric composite materials simulating the characteristics of human skull behaviors and the brain model produced is made from gellarin Headform structure is made by means of hand-lay up method; it consists of six layers of chopped strand mat (CSM) fiber. The headforms equipped with or without industrial safety helmet were impacted to fracture with a blunt end load striking bar, using an air gun compressor The load striking bar is accelerated by a striking bar shot out from the air gun apparatus. The incident stresses transmitted into the headform are calculated by using a two-gage method. To obtain the response of headform directly around the vicinity of impact location, two strain gages were pasted at location X and Y Both strain gages are 15 mm and 30 num away from impact location. The result of a new headform model made of GFRP polymeric composite materials is helpful in the analysis of human skull fracture. The results of impact using two-gage obtained the structure integrity of the headform may resist up to 8,42 MPa, at impact distance of 140 mm. The average stress transmission factor is around 13,38% Headform with gellatin response using direct impact obtained the stress resist up-1,62 MPa in X direction and 2,78 MPa in Y direction (15 mm from impact location) to pariental region. Comparing both stress responses, the headform experiences larger stress in X direction than that of Y direction. Headform respore with indirect impact (with helmet) obtained the stress resist up 0.55 MPa. Industrial safety helmets functioned very well in absorbing the impact loading (at the average 95%). The absorbed transmitted stress is less than the stress tolerances of bone skull. Due to the direct impact loading, headform is damage. The damage of headform started on matrix cracking and followed by the process of whitening zone. The damage behavior of the headform can be observed from inside of the headform. A mumerical study calculation using MSC/NASTRAN 3D was conducted and the Solidwork 3D software is used to make headform modeling. Base on experimental result and FEM simulation clarified that stress differences Le 6,33%. The result of FEM simulation obtained the configurations of stresses are similar to the one obtained experimentally using two-gage method. It is also noted that the Y direction of stress is less than of X direction