저온환경하 콘크리트 시공을 위한 저온경화형 모르타르 및 거푸집 개발에 관한 실험적 연구

Abstract

최근 국내의 건설시장의 과포화로 인해 국내 주요 건설사들은 해외 건설시장을 개척하고자 하는 적극적인 움직임을 보이고 있으며, 최근에는 몽골이나 러시아와 같은 극한대 지역까지 진출하거나, 진출을 준비하고 있는 현황이다. 이러한 현황에서 해외 건설시장에서 건설기술의 우위를 선점하기 위하여 해외 현지여건에 부합하는 맞춤형 기술력을 확보하기 위한 지속적인 연구가 필요하다고 판단되지만, 현재까지는 실험실에서 실시된 영상의 저온환경에서 진행된 연구들이 대부분이며, 영하의 저온환경 수준에 초점을 맞춘 연구는 부족한 실정이다. 본 연구에서는 영하의 저온환경하에서 가열보온양생을 적용하지 않은 시멘트계 재료의 물성을 파악하고자 하였다. 1차적으로 방동제와 경화촉진제를 사용하여 시멘트계 재료의 재령에 따른 Ca(OH)2생성량, 화합결합수량 및 공극분포의 변화를 측정하여 영하의 저온환경하에서 시멘트계 재료의 수화반응을 파악하고자 하였으며, 2차적으로 방동제와 단열거푸집을 적용하여 거푸집 내부에 타설된 시멘트계 재료의 온도이력 및 압축강도를 측정하여 분석하였다. 더 나아가, 단열거푸집 내부 시멘트의 초기 수화반응을 촉진시키기 위한 고분말도 시멘트와 발열거푸집의 적용을 고려하여 저온환경에서 콘크리트 시공을 위해 사용할 수 있는 재료 및 시공측면의 방안을 실험적으로 검토하여 기초정보를 얻고자 하였다. 실험 결과, 저온환경하 모르타르의 지속적인 강도발현, 모세관공극의 감소 및 화학결합수 및 수화생성물의 량이 증가하는 것을 확인 할 수 있었으며, 경질우레탄 단열거푸집과 고분말도 시멘트를 함께 사용했을 때, 가장 우수한 온도이력 및 강도발현을 나타내었고, 초기재령 3일에 5N/mm2 이상을 발현하는 것이 가능할 것으로 판단된다. 하지만 영하 -10℃ 이하의 열악한 극한환경에서, 단열거푸집의 사용만으로는 시멘트계 재료의 표면동결이 우려되는 상황이다. 따라서, 추후 단열거푸집과 발열필름을 함께 적용하여 단열거푸집으로 강도를 확보하는 한편 발열필름으로 시멘트계 재료의 표면동결을 방지하는 연구가 필요할 것으로 사료된다.| Due to the saturation of the domestic construction market recently, major domestic construction companies are actively moving to open up overseas construction market or already entered to the extreme for areas such as Mongolia or Russia recent years. Such status is determined, more research to ensure the customized technology to meet the overseas conditions is necessary in order to preempt the lead in the overseas construction market in construction technology, the most studies conducted above 0℃ in laboratory level, and research focused on the low-temperature environment of the freezing level is lacking. In this study, the physical properties of cementitious materials have not been applied to heat insulating curing was to determine a low-temperature environment of below freezing. Primarily, measuring the change of compound bound water and the pore distribution to determine the hydration of cementitious materials under freezing in a low temperature environment according to the age of the cementitious material Ca(OH)2 production by using anti-freezing agent and curing accelerator. Secondarily, conduct analyzing by measuring the temperature history and the compressive strength of the cementitious material poured inside the form by applying anti-freezing agnet and insulated form. Furthermore, to consider application of high fineness cement and heat insulating form to promote early hydration reaction of cement inside of inuslated form. An experimental study was conducted to obtain basic information for concrete casting in a low temperature environment by considering the available materials and construction method. As result of experiment, constant strength development of mortar at low-temperature environment, decrease of the capillary pores, and the amount of chemical bond water increment could be determined. When used with a rigid urethane insulating form with high fineness cement, it showed the highest Strength Development and temperature history, it is determined to be capable of expressing more than 5N/mm2 in early age. But, in the more harsh condition, such as below -10℃ extreme temperature environment, the use of insulated form is concerned situations in which the surface freezing of cementitious materials. Therefore, additional researches are needed about cementitious material applied insulating form and heating the film together to secure the long age strength by insulated form, prevent the surface freezing by heating film; Due to the saturation of the domestic construction market recently, major domestic construction companies are actively moving to open up overseas construction market or already entered to the extreme for areas such as Mongolia or Russia recent years. Such status is determined, more research to ensure the customized technology to meet the overseas conditions is necessary in order to preempt the lead in the overseas construction market in construction technology, the most studies conducted above 0℃ in laboratory level, and research focused on the low-temperature environment of the freezing level is lacking. In this study, the physical properties of cementitious materials have not been applied to heat insulating curing was to determine a low-temperature environment of below freezing. Primarily, measuring the change of compound bound water and the pore distribution to determine the hydration of cementitious materials under freezing in a low temperature environment according to the age of the cementitious material Ca(OH)2 production by using anti-freezing agent and curing accelerator. Secondarily, conduct analyzing by measuring the temperature history and the compressive strength of the cementitious material poured inside the form by applying anti-freezing agnet and insulated form. Furthermore, to consider application of high fineness cement and heat insulating form to promote early hydration reaction of cement inside of inuslated form. An experimental study was conducted to obtain basic information for concrete casting in a low temperature environment by considering the available materials and construction method. As result of experiment, constant strength development of mortar at low-temperature environment, decrease of the capillary pores, and the amount of chemical bond water increment could be determined. When used with a rigid urethane insulating form with high fineness cement, it showed the highest Strength Development and temperature history, it is determined to be capable of expressing more than 5N/mm2 in early age. But, in the more harsh condition, such as below -10℃ extreme temperature environment, the use of insulated form is concerned situations in which the surface freezing of cementitious materials. Therefore, additional researches are needed about cementitious material applied insulating form and heating the film together to secure the long age strength by insulated form, prevent the surface freezing by heating film