惡化環境對於輕質骨材混凝土之耐久性影響

Durability of Lightweight Aggregate Concretes Subject to Different Deterioration Environments

陳靖宇(Jing-Yu Chen)

指導教授 ： 李明君

朝陽科技大學/理工學院/營建工程系/碩士(2012年)

摘要

本研究針對『惡化環境對於輕質骨材混凝土之性質劣化影響』進行探討評估，配比設計包括普通混凝土、兩種輕質骨材混凝土與輕質骨材透水混凝土，本期主要是針對輕質骨材混凝土之耐久性質研究，惡化環境包括海水乾濕浸泡與加速凍融劣化環境二種，試體於上述環境下進行相關測試，包括（1）抗壓強度，（2）抗彎強度，（3）透水透氣能力試驗，（4）衝擊磨損試驗，（5）巨觀與微觀分析。
研究結果顯示，使用比重較大之輕質骨材之混凝土其強度與單位重較大，輕質骨材混凝土單位重低於普通混凝土，以輕質骨材取代等體積10%與20%之常重骨材則其強度低於普通混凝土約20%。在加速凍融循環試驗中，混凝土試體會隨著循環次數的增加，初期強度會略增，後期強度則減少；經加速凍融循環600回後，輕質骨材混凝土之強度折減程度優於普通混凝土；但經海水乾溼循環70回試驗後，普通混凝土與輕質骨材混凝土其抗壓強度皆高於初始值，且循環後之試體並未出現龜裂現象。
關鍵字：輕質骨材、吸水性、強度、耐久性

關鍵字

耐久性 ； 強度 ； 吸水性 ； 輕質骨材

並列摘要

In this study, the durability of lightweight aggregate concrete subject to different lightweight aggregates and deterioration environments is assessed. Five mix design concretes included ordinary concrete, two lightweight aggregate concrete and one permeable lightweight aggregate concrete. This project aims to run the durability of lightweight aggregate concrete in two deteriorating environments, including sea water dry-wet immersion with programmable temperature and accelerated freeze-thaw cycling tests. The study was tested and evaluated by the following items: (1) compressive strength, (2) flexural strength, (3) air and permeable capacity test, (4) impact abrasion test, (5) macro and microscopic analysis.
The results showed that the higher specific weight of lightweight aggregate concrete would exhibit relatively high strength and unit weight. In the same water-cement ratio level, the strength of lightweight aggregate concrete is lower than ordinary concrete about 20% strength. At the accelerated freeze-thaw test, the strength of concrete will increase with the freeze-thaw cycles at initial stage. The ratio of strength reduction of lightweight aggregate concrete specimens was better than those of normal concrete ones after 600 freeze-thaw cycles. After 70 drying and wetting cycles of sea water immersion test, the strength of lightweight aggregate concrete and normal concrete was higher than the initial value, and the cracking of concrete specimens does not appear.
Keywords: lightweight aggregate, water absorption, strength, durability

並列關鍵字

durability ； strength ； water absorption ； lightweight aggregate

參考文獻

【6】 F’ed’eration Internationale de la Pre’contrainte（FIP）,“FIP Manual of Lightweight Aggregate Concrete”,Surrey University Press, London, 1983.

【7】 American Concrete Institute,”Guide for Structural Lightweight Aggregate Concrete”,report by ACI Committee 213,ACI213R-87, in Manual of Concrete Practicr,1987.

【23】 鄭文信，「人造輕質骨材混凝土耐久性之研究」，碩士論文，國立成功大學土木工程研究所，2006。

【26】 湯兆緯，「輕質粒料混凝土污工單元之簡介」，輕質骨材混凝土產業成果研討會，2007年9 月。

【28】 何政翰，「不同輕質骨材對於輕質骨材混凝土之耐久性影響」，碩士論文，朝陽科技大學營建工程研究所，2009。