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Microstructure and Strength Characteristic of Hydropobic Cement Mortar with Silan Admixture

실란계 혼화제가 혼입된 소수성 시멘트 모르타르의 미세구조 및 강도특성

  • Kim, Younghwan (Department of Civil Engineering, Gyeonsang National University) ;
  • Oh, Hongseob (Department of Civil Engineering, Gyeonsang National University)
  • 김영환 (경상국립대학교 토목공학과) ;
  • 오홍섭 (경상국립대학교 토목공학과)
  • Received : 2021.02.09
  • Accepted : 2021.04.01
  • Published : 2021.06.30

Abstract

A hydrophobic emulsion consisting of PMHS and PVA was mixed into a cement mortar to observe changes in cement hydrate and microstructure, and to experimentally evaluate compressive strength and flexural strength. The hydrophobic emulsion was added with metakaolin and PVA fibers, and the stirring speed and sequence were adjusted to prepare a shell-concept hydrophobic emulsion. It was then mixed when mixing mortar to enhance filling of the internal pores and change of the hydrates. It was observed that the mortar mixed with a hydrophobic emulsion was filled with micropores and a coating film was formed on the surface of the hydrates by the emulsion. It was analyzed that the total pore area and porosity of the mortar mixed with the emulsion decreased from 30% to 60% compared to OPC, excluding the 50MK variable, which was extremely reduced and the median pore diameter decreased in some variables. It was also found that the compressive strength of the mortar mixed with emulsion 1% was increased up to 20%, but the strength of the mortar specimen mixed with 2% decreased to 50%.

PMHS와 PVA를 혼합한 소수성 유액을 시멘트 모르타르에 혼입하여 수화생성물과 미세구조의 변화를 관찰하고, 압축강도와 휨강도를 실험적으로 평가하고자 하였다. 소수성 유액은 메타카올린과 PVA 섬유를 추가하고 교반속도와 순서를 조정하여 쉘형태의 유액을 제조하였으며, 모르타르배합시 혼입하여 내부 공극의 충진과 수화생성물의 변화를 도모하고자 하였다. 소수성 유액이 혼입된 모르타르는 미세공극이 충진되고 수화생성물표면이 유액에 의해 도막이 생성되는 것이 관찰되었다. OPC와 비교하여 유액이 혼입된 모르타르의 전체 기공면적과 기공률이 감소하는 것으로 분석되었으며, 일부 변수에서 기공지름의 중간값의 감소가 나타났다. 유액을 1% 혼입한 경우에 압축강도의 증가가 나타났으며, 2% 혼입시에는 강도의 감소가 발생하였다.

Keywords

Acknowledgement

이 논문은 한국연구재단 이공분야 기초연구사업(NRF-2018R1D1A1B07049278)의 지원에 의해 수행되었으며, 저자들은 이에 감사드립니다.

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