高飛灰量混凝土之製作與性質

發表於台電工程月刊，第737期，民國99年1月

高飛灰量混凝土之製作與性質

The Fabrication and Properties of High Volume Fly Ash Concrete

黃兆龍*	賴正義*	謝素蘭**
Hwang, Chao- Lung	Lai, Cheng-I	Hsieh, Su-Lan

摘　要

近年來台電公司所產飛灰的利用率逐年下降，造成飛灰有用資源的浪費，影響台電燃煤電廠灰塘的使用年限，也衝擊未來新電廠的興建與既有電廠的運作。對於飛灰取代水泥比率超過50%之高飛灰量混凝土，國外已有多年的研究成果，若能引進其產製技術，並加以推廣，國內飛灰的需求量將會大幅增加。本文概述高飛灰量混凝土製作時的考量因素，如需水量、配比、澆置、養護等，並介紹坍度、含氣量、泌水、密度、凝結、乾縮、溫度裂縫等新拌混凝土性質，抗壓強度、撓曲強度、彈性模數、水密性、潛變等硬固混凝土性質，以及氯離子滲透、鹼矽反應、硫酸鹽、磨擦、中性化、凍融、除冰鹽剝落、疲勞等耐久性，期能做為我國推動高飛灰量混凝土時之參考。

Abstract

Recently, the utilization percentage of fly ash produced by Taiwan Power Company has been decreasing annually. It may not only cause the waste of fly ash as a valuable resource, but also severely impact the service life of ash pond and even the construction of new power plants as well as the operation of existing ones of Taiwan Power Company. As to high volume fly ash concretes which have more than 50% cement substituted by fly ash, substantial research outcomes can be found in many foreign countries. Provided the fabrication techniques are introduced to Taiwan, the domestic need of fly ash will increase significantly. In the paper a few factors, such as water requirement, mix proportion, casting and curing, considered in the process of fabrication are briefly explained. Then the properties of fresh concrete including slump, air content, bleeding, density, setting, drying shrinkage as well as thermal cracking, and the properties of hardened concrete containing compressive strength, flexural strength, modulus of elasticity, water tightness as well as creep are introduced. Also, some durability characteristics in terms of chloride ion penetration, alkali-silica reaction, sulfate attack, abrasion, carbonation, freezing and thawing, de-icing salt along with fatigue are presented. It is expected such a paper can be a viable reference for promotion of high volume fly ash concretes in Taiwan.