本文關(guān)鍵詞：玄武巖纖維對低溫下鋼渣粉混凝土力學(xué)性能影響的試驗(yàn)分析　出處：《安徽理工大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 鋼渣粉 玄武巖纖維 低溫 抗壓強(qiáng)度 劈裂抗拉強(qiáng)度 養(yǎng)護(hù)齡期

【摘要】：目前,隨著社會對低碳環(huán)保要求的提高,用鋼渣粉替代水泥制成的鋼渣粉混凝土,以其和易性良好和水化熱低等優(yōu)點(diǎn)受到普遍關(guān)注。但是鋼渣粉混凝土也存在強(qiáng)度增長慢、早期強(qiáng)度較低、抗裂性差和鋼渣粉高摻量時導(dǎo)致混凝土的強(qiáng)度降低幅度較大等問題。我國近半國土在冬季時氣溫低于零度,對于冬季的工程施工,低溫條件下混凝土強(qiáng)度的降低就是一個必須考慮的問題。鋼渣粉作為摻和料對混凝土的抗凍性有一定的改善。玄武巖纖維抗拉強(qiáng)度高、耐低溫和抗裂性良好等優(yōu)點(diǎn),將其與鋼渣粉復(fù)合摻入改善早期強(qiáng)度為鋼渣粉混凝土在寒區(qū)的應(yīng)用打開一條新思路。本文首先研究了玄武巖纖維摻量為3kg/m~3下鋼渣粉摻量和養(yǎng)護(hù)齡期對玄武巖纖維鋼渣粉混凝土壓拉性能的影響,得出鋼渣粉混凝土的強(qiáng)度增長規(guī)律和合適的鋼渣粉摻量。在此基礎(chǔ)上研究在合適鋼渣粉摻量下不同低溫養(yǎng)護(hù)條件時,不同摻量的玄武巖纖維對鋼渣粉混凝土壓拉強(qiáng)度的影響。首先,進(jìn)行了不同齡期下鋼渣粉對混凝土壓拉強(qiáng)度影響的試驗(yàn),其中養(yǎng)護(hù)齡期分別為7d、14d、28d,鋼渣粉摻量為0%、12%、15%、18%、20%。試驗(yàn)結(jié)果相較于不摻鋼渣粉的混凝土,混凝土摻入鋼渣粉后其28d壓拉強(qiáng)度與未摻入組基本持平或略有提高,在鋼渣粉摻量為15%時達(dá)到最優(yōu),抗壓強(qiáng)度提高了 2.6%,劈裂抗拉強(qiáng)度提高了 9.2%;在養(yǎng)護(hù)齡期為14d時,在鋼渣粉摻量12%時抗壓強(qiáng)度達(dá)到最優(yōu),提高了 7.5%,劈裂抗拉強(qiáng)度在鋼渣粉量20%時達(dá)到最優(yōu),提高了 4.4%;在養(yǎng)護(hù)齡期為7d時,混凝土的壓拉強(qiáng)度均隨著鋼渣粉摻量的增加而降低。通過對不同摻量的鋼渣粉混凝土在不同齡期的強(qiáng)度發(fā)展規(guī)律對比得,玄武巖纖維鋼渣粉混凝土早期強(qiáng)度發(fā)展較慢,后期強(qiáng)度發(fā)展較快,且其28d強(qiáng)度略高或基本持平于不摻鋼渣粉混凝土的強(qiáng)度。在此基礎(chǔ)上進(jìn)行了以玄武巖纖維摻量分別為0kg/m~3、2kg/m~3、3kg/m~3、4kg/m~3、5kg/m~3,養(yǎng)護(hù)溫度為標(biāo)準(zhǔn)養(yǎng)護(hù)、-5℃、-10℃、-15℃、-20℃的正交試驗(yàn),共25組。與各自養(yǎng)護(hù)溫度下未摻纖維組比較,在養(yǎng)護(hù)溫度為標(biāo)準(zhǔn)養(yǎng)護(hù)和-5℃時,在玄武巖纖維在3kg/m~3時,混凝土強(qiáng)度達(dá)到最大,抗壓強(qiáng)度分別提高了 3.9%和7.4%,劈裂抗拉強(qiáng)度分別提高了 11.5%和7.8%;在養(yǎng)護(hù)溫度為-10℃、-15℃和-20℃時,玄武巖纖維為4 kg/m~3時,混凝土強(qiáng)度達(dá)到最大,抗壓強(qiáng)度分別提高了 8.9%、8.9%和17.9%,劈裂抗拉強(qiáng)度分別提高了 8.9%、10.5%和23.1%。標(biāo)準(zhǔn)養(yǎng)護(hù)下未摻入纖維的鋼渣粉混凝土強(qiáng)度為38.8MPa。與其相比在低溫-5℃、-10℃、-15℃、-20℃養(yǎng)護(hù)下?lián)饺胄鋷r纖維的混凝土,其最大抗壓強(qiáng)度可達(dá)100.7%、98.9%、98.2%、98.2%,最大劈裂抗拉強(qiáng)度可達(dá)96.9%、94.1%、92.3%、91.3%。試驗(yàn)結(jié)果表明:在低溫條件下使用的鋼渣粉混凝土在摻入玄武巖纖維后,強(qiáng)度得到有效提高,接近標(biāo)養(yǎng)下的普通鋼渣粉混凝土的強(qiáng)度。說明玄武巖纖維可以較好的改善鋼渣粉混凝土低溫環(huán)境下的抗凍能力。
[Abstract]:At present, with the society to improve the requirements of low-carbon environmental protection, steel slag powder instead of cement made of steel slag concrete. Due to the advantages of good compatibility and low hydration heat, steel slag powder concrete also has slow strength growth and low early strength. Poor crack resistance and high content of steel slag powder lead to large reduction of concrete strength. The temperature of nearly half of our country is lower than zero in winter, so the engineering construction in winter is carried out. The reduction of concrete strength at low temperature is a problem that must be considered. Steel slag powder as admixture can improve the frost resistance of concrete to some extent, and the tensile strength of basalt fiber is high. Low temperature resistance and good crack resistance and other advantages. The application of steel slag concrete in cold region is a new way to improve the early strength by adding it to steel slag powder. In this paper, the content and curing age of steel slag powder with basalt fiber content of 3 kg / m ~ (3) are studied firstly. The influence on the compressive and tensile properties of basalt fiber steel slag powder concrete. The strength growth law and the appropriate amount of steel slag powder are obtained. On this basis, the different low temperature curing conditions under the appropriate steel slag powder content are studied. The effect of basalt fiber on compressive tensile strength of steel slag concrete was studied. Firstly, the effect of steel slag powder on compressive tensile strength of concrete was tested at different ages, and the curing age was 7 days or 14 days respectively. At 28 days, the amount of steel slag powder was 0 and 12%. The test results were compared with the concrete without steel slag powder. The compressive tensile strength of concrete mixed with steel slag powder is basically equal to that of unadulterated group for 28 days, and the compressive strength is increased by 2.6% when the content of steel slag powder is 15. Splitting tensile strength increased 9.2%; When the curing age is 14 days, the compressive strength of steel slag powder reaches the optimum when the content of steel slag powder is 12, and increases 7.5. the splitting tensile strength reaches the optimum when the steel slag powder content is 20, and increases 4.4. When the curing age is 7 days, the compressive tensile strength of concrete decreases with the increase of steel slag powder content. The early strength development of basalt fiber steel slag powder concrete is slow and the later strength development is faster. On the basis of this, the basalt fiber content is 0 kg / m ~ 3 ~ 3 kg / m ~ (-1) ~ 3kg / m ~ (-1) ~ 3 ~ (-1) ~ 3kg ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1) ~ (-1). The standard curing temperature is -5 鈩，

本文編號：1429872