저온환경하 콘크리트 시공을 위한 영하온도 경화가능형 시멘트 모르타르 및 단열·발열거푸집 개발에 관한 실험적 연구

Abstract

Domestic construction market is congested enough at the moment cause enterprises to enter overseas market such as Mongolia and Russia. However most previous studies conducted at a temperature above freezing. In this study, performance analysis of cement mortar was conducted without extra heating air supplying at a low temperature below freezing. For this study, all of materials for experiment were kept in a low temperature for 48 hours before mortar mixing. After mortar curing at low temperature, compressive strength was measured at the early ages. Also, properties of hardened cement material was analysed using TG-DTA and MIP. At experiment series 1, to figure out whether cement hydration reaction at low temperature below freezing is possible or not, use anti-freezing agent to protect freezing of water used in mortar mixture and analyze increasing amount of Ca(OH)2, chemical bound water contained in mortar by usage of hardening accelerator and curing period at low temperature condition. At experiment series 2, insulated and heating form have been used with mortar has same mix proportion as series 1. Thermal performance and compressive strength of mortar are conducted and analyzed excremental result according to the variable form types. Especially, high fineness cement is considered to use with insulated form. Hydration heat of quicklime is used for heating form in this study. The analysis of this study confirmed that high fineness cement with insulated form and heating form can be suitable to be used in low temperature environment.