塑性混凝土於截水牆之性能評估

Performance Evaluation of Plastic Concrete for Cut-off Wall

鄭凱蔚(Kai-Wei Cheng)

指導教授 ： 詹穎雯

國立臺灣大學/工學院/土木工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201702901

摘要

由於幾年塑性混凝土這項材料才首次在台灣的工程中使用，因此國內對此材料的認知並不完善，例如其高水膠比及較低的彈性模數要求，就顛覆一般對混凝土的認知，為了日後可能在興建水壩或圍堰工程等會有截水牆工程，故需要對塑性混凝土這項材料在進行更多的研究。
本研究主要以達成工程規範及工程應用性為目標，探討當皂土添加入混凝土後的特性，其包含新拌性質的坍度及硬固性質的抗壓試驗、彈性模數試驗、滲透性試驗、乾縮試驗等，其中需要考慮到的因素有水膠比、皂土取代率以及皂土種類，並先由水泥砂漿配比來著手實驗，得到大致的趨勢在進入塑性混凝土階段的研究。其中水泥是採用台泥二型水泥，此乃顧慮到環境可能會對混凝土造成侵害，所以採用較能抵擋化學侵害的水泥，而皂土方面本研究採用了Hydorgel(H皂土)和Bentonil API(A皂土)這兩種皂土，來比較皂土種類對塑性混凝土在性質上的差異。
最後考慮到社會所重視的環保議題，因此在材料的使用上若能減少水泥的用量，期望為地球環境貢獻一份心力，故在材料上選擇了國內容易取得的爐石這項卜作嵐材料來取代水泥用量，並探究其成效能否符合工程規範，然而發現添加爐石後對於塑性混凝土強度及彈性模數大幅提升，有待日後進行更多相關研究。

關鍵字

塑性混凝土 ； 截水牆 ； 皂土 ； 二型水泥 ； 爐石

並列摘要

This is the first time that plastic concrete is used in Taiwan’s engineering this years, so the domestic cognition of this materials is not popular, such as its high water ratio and lower elastic modulus requirements are subverted in the general knowledge of concrete. For the possibility to construct the dam, which will have a cut-off wall works, it is necessary to study more on plastic concrete in the future.
We investigate the property of concrete after adding bentonite in this paper, and our objective is to meet the engineering specification. It contains the fresh and hardening properties of the concrete includes the slumps test, the elastic modulus test, the penetration test, shrinkage test, which need to take into account the factors of water-cement ratio, bentonite replacement rate and the type of bentonite. At the first by the cement mortar to start the experiment, get a general trend then continue the experiment on plastic concrete. The study is the use of type Ⅱ cement, which is concerned about the environment may cause damage to concrete, and bentonite in this study using Hydorgel (H bentonite) and Bentonil API (A bentonite) to compare the properties with different types of bentonite.
In order to reduce the use of cement, we chose slag which is easy to get in Taiwan to replace cement. The other benefit is that engineering qualification can be achieved. We wish the replacement of pozzolanic material could lower the CO2 emissions, and makes plastic concrete more environmental friendly.

並列關鍵字

Plastic concrete ； Cut-off wall ； Bentonite ； type Ⅱ cement ； slag

參考文獻

[26] 台灣營建研究中心，「水泥皂土之性質研究」，財團法人台灣營建研究中心，74年11月。

[38] 鄭百宏等人，塑性混凝土試驗期中報告，財團法人台灣營建研究院，106年5月

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