Mix Proportions of High Flowable Early Strength Mortar for Emergency Repair of Damaged Road Base in Rural Area

Abstract:

Recently, due to the climate changes, the frequency and severity of natural disasters such as torrential rain have become more significant worldwide. In South Korea, there are number of summer typhoons and localized torrential downpour every year and these cause severe damages onto a residential area and road networks. More than 70% of the land of Korean peninsula is a mountainous area and thus damages onto road networks result in serious harm to daily lives especially in a rural area by isolating residents from networks. Therefore, there is a strong demand on the immediate and emergency repair technology for the collapsed road networks. This study develops an emergency repair technique for damaged road base where the damaged road base can be packed with gravels and then the pores or open-gaps of the packed gravels can be filled with high flowable mortar that develops strength in an early age. The aim of this research study was to find the suitable mix proportions of high flowable early strength mortar. Throughout the experimental work, study was done on two stage mix variables, where in the 1^st stage, W/C ratio and high range water reducer was considered whereas in the 2^nd stage cost effective early strength cement was used for the mix-design. With various variables in mix proportions, compressive strength and flow capacity were investigated. Finally from those experimental study, optimum mix proportions of the high flowable early strength mortar was found. The hardened materials composited with gravels and mortars can be used as a permanent road base with no need for compaction thereafter.

• Periodical: Key Engineering Materials (Volume 723)
• Pages: 836-842
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.723.836
• Online since: December 2016
• Authors: Cheol Woo Park, Jang Yong Lee, Yong Jae Kim, Seung Won Kim*
• Keywords: Damaged Road, Emergency Repair, High Flowable Early Strength Mortar, Natural Disaster

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