Influence of alkali-resistant glass fiber on seismic performance of precast ceramsite concrete sandwich wall panels

Abstract

Shear wall, which is a component commonly used in high-rise building to resist the side force, has been widely applied in earthquake-prone regions. In this paper, a new type of prefabricated alkali-resistant glass fiber ceramsite concrete sandwich composite shear wallboard is proposed, which is composed of the polystyrene insulation board set in the middle and the alkali-resistant glass fiber ceramsite concrete boards set at both sides. This type of sandwich composite shear wallboard solves multiple problems of ordinary wallboard insulation materials from the perspective of structural form, including hidden risks of fire and peeling-off. Research experience shows that alkali-resistant glass fiber has high tensile, bending, crack, impact and alkali resistance, so adding the alkali-resistant glass fiber into concrete can improve its strength, toughness, crack resistance and corrosion resistance. Due to the existence of fiber, the cracks of cracked wallboard will open and close repeatedly under low reversed cyclic loading, so it can effectively absorb more seismic energy. Besides, the ceramsite concrete is featured in comparatively small elastic modulus and light mass, which help to reduce the dead weight of the wallboard. In a word, this kind of wallboard can effectively weaken the impacts of earthquake force and improve the overall seismic performance of wallboard structure. Therefore, in this paper, three types of specimens are designed with different admixture volumes of alkali-resistant glass fiber, respectively: 0%, 0.3%, and 0.4%. Through the experimental study on the seismic performance of the specimens, the influence law of different alkali-resistant glass fiber content on the seismic performance of the specimens is obtained. The study results show: compared with ordinary wallboard, the cracking displacement of the specimens with 0.3% and 0.4% fiber admixtures are improved by 42.63% and 35.79% respectively. This indicates that the fiber can delay the cracking of the test piece and improve the functional coordination among various materials, thereby easing the deformation of the overall wallboard when bearing forces. When the admixture amount of fiber reaches 0.3%, the specimen shows excellent performance in various seismic indicators, such as hysteresis, ductility, and energy consumption, presenting good application prospects. However excessive fiber admixture in ceramsite concrete actually has no good effect on the overall performance improvement of the wallboard. Therefore, in practical construction, this type of fiber shall not be added randomly.