고온ㆍ고습 환경 하에서의 CFRP 모자형 단면부재의 강도평가

Abstract

It is important to satisfy the requirements and standards for the protections of passengers in a car accident. There are lots of studies on the crushing energy absorption of a structure members in automobiles. In this paper, we have studied to investigate collapse characteristics and moisture absorption movements of CFRP structure members when CFRP(carbon fiber reinforced plastics) laminates are under the hygrothermal environment. In particular, the absorbed energy, mean collapse load and deformation mode were analyzed for side members which absorbed most of the collision energy. Also, variation of CFRP interlaminar numbers is important to increase the energy absorption capability. Therefore we have made a static collapse experiment to research into the difference of absorbed energy and deformation mode between moisture absorbed specimen and non-moisture absorbed. The purpose of this study is to evaluate the strength reduction and moisture absorption behavior of CFRP hat shaped member, moisture absorption test and static collapsing were conducted, and the following conclusions were achieved. For the moisture absorption behavior by the change in interlaminar numbers, 2 and 3 interlaminar showed a steep increase in absorption rate at the initial stage, but absorption rates for all specimens showed consistent increment after 1.0%. Collapsing shapes for moisture absorbed specimen and the one without moisture absorption displayed the weakening of bonding strength between interfaces due to internal deterioration of CFRP. In addition, collapsed shape and mode for moisture absorbed specimen exhibited more stabilized collapsing mode. Strength of moisture absorbed specimen was reduced by 12% from the one without moisture absorption.