考慮水壓力情況下地鐵管片混凝土的硫酸鹽侵蝕試驗與分析
本文選題:地鐵管片混凝土 + 水壓力。 參考:《華南理工大學》2014年碩士論文
【摘要】:目前,我國建有大量地鐵隧道。地鐵管片混凝土是一種典型的多孔介質(zhì),外部環(huán)境的硫酸鹽通過孔隙擴散到混凝土內(nèi)部并與其中某些礦物成分發(fā)生反應,使得管片的力學性能發(fā)生劣化。地鐵隧道深埋地下,,地下水壓力的存在可能加速硫酸鹽的侵入,促使管片劣化更快。為了探討有水壓力情況下硫酸鹽對地鐵管片混凝土的侵蝕作用,本文開展了如下工作: 1、針對地鐵管片混凝土立方體試塊和圓柱體試塊,開展了其在無水壓力的硫酸鈉溶液中浸泡30、60、90、120、150天之后的抗壓強度和硫酸根離子濃度試驗。研究表明:(1)隨著浸泡時間的增加,管片混凝土的抗壓強度呈現(xiàn)先增后減的變化趨勢,浸泡60天后達到最大值(;2)隨著深度的增加,管片混凝土內(nèi)部的硫酸根離子濃度迅速減小,且在深度1.5mm和4.5mm之間出現(xiàn)陡降;(3)對應相同深度,圓柱體內(nèi)部的硫酸根離子濃度相比立方體略高。 2、針對地鐵管片混凝土立方體試塊和圓柱體試塊,開展了其在5m、10m、15m水壓力的硫酸鈉溶液中浸泡30、60、90、120、150天之后的抗壓強度和硫酸根離子濃度的試驗。研究表明:(1)與無水壓力情況相比,上述水壓力并未就硫酸鹽對地鐵管片混凝土的侵蝕作用產(chǎn)生明顯影響;(2)本文所用壓力裝置不僅構(gòu)造簡單,而且壓力穩(wěn)定。 3、對Tixier R擴散模型進行了改進,并利用其模擬硫酸根離子在地鐵管片混凝土中的擴散過程,將模擬結(jié)果與試驗結(jié)果進行了對比。研究表明:改進后的擴散模型可較好地再現(xiàn)硫酸根離子在管片混凝土中的擴散行為。 4、假設(shè)硫酸鹽侵蝕后管片混凝土的抗壓強度是硫酸根離子濃度的特定函數(shù),提出了侵蝕后管片混凝土抗壓強度計算模型,將計算結(jié)果與試驗結(jié)果進行了對比。研究表明:采用該模型計算得到的侵蝕后管片混凝土抗壓強度與試驗結(jié)果吻合較好。
[Abstract]:At present, our country has a large number of subway tunnels. Subway segment concrete is a kind of typical porous medium. The sulphate in the external environment diffuses into the concrete through the pore and reacts with some mineral components in the concrete, resulting in the deterioration of the mechanical properties of the segment. The existence of groundwater pressure may accelerate the invasion of sulphate and accelerate the deterioration of segments. In order to study the erosion effect of sulfate on the concrete of metro segment under water pressure, the following work has been carried out in this paper: 1. The compressive strength and the concentration of sulfate ion were tested after soaking in the solution of sodium sulfate under anhydrous pressure for 30 ~ 60,90120150 days. The results showed that: (1) with the increase of soaking time, the compressive strength of segment concrete increased first and then decreased, and reached the maximum after 60 days of immersion. The concentration of sulfate ion in segment concrete decreases rapidly, and there is a sharp drop between the depth of 1.5mm and 4.5mm. (3) the same depth is corresponding to the concentration of sulfate ion. The concentration of sulfate ion in the cylinder is slightly higher than that in the cube. 2. The compressive strength and the concentration of sulfate ion in sodium sulfate solution at water pressure of 5 m ~ 10 m ~ (15 m) were tested after immersion for 30 ~ 60,90120150 days. The results show that: (1) compared with the case of anhydrous pressure, the water pressure has no obvious effect on the erosion effect of sulfate on the concrete of subway segments, (2) the pressure device used in this paper is not only simple in construction, And the pressure is stable. 3. The Tixier R diffusion model is improved, and the diffusion process of sulfate ion in concrete is simulated. The simulation results are compared with the experimental results. The results show that the improved diffusion model can reproduce the diffusion behavior of sulfate ion in concrete segments. 4. Assuming that the compressive strength of the concrete after sulfate erosion is a specific function of the concentration of sulfate ion. A model for calculating the compressive strength of corroded segment concrete is proposed, and the calculated results are compared with the experimental results. The results show that the compressive strength of the corroded segment concrete calculated by this model is in good agreement with the experimental results.
【學位授予單位】:華南理工大學
【學位級別】:碩士
【學位授予年份】:2014
【分類號】:U231;U454
【參考文獻】
相關(guān)期刊論文 前10條
1 程選生;杜永峰;史曉宇;李慧;;黃土對地下貯庫的濕陷敏感性及化學侵蝕影響[J];地下空間與工程學報;2006年06期
2 涂永明,呂志濤;應力狀態(tài)下混凝土的碳化試驗研究[J];東南大學學報(自然科學版);2003年05期
3 張文淵;沿海地區(qū)水工建筑物混凝土的腐蝕與防護措施[J];工程質(zhì)量;2002年02期
4 葉銘勛;;混凝土碳化反應的熱力學計算[J];硅酸鹽通報;1989年02期
5 王復生,孫瑞蓮,秦曉娟;察爾汗鹽湖條件下水泥混凝土耐久性調(diào)查研究[J];硅酸鹽通報;2002年04期
6 俞海勇;鞠麗艷;;上海城市軌道交通工程混凝土結(jié)構(gòu)耐久性設(shè)計與實踐[J];地下工程與隧道;2009年S1期
7 杜應吉,李元婷;活性摻合料對地鐵混凝土雜散電流的抑制作用[J];混凝土;2005年06期
8 黃戰(zhàn);邢鋒;邢媛媛;董必欽;羅帥;;硫酸鹽侵蝕對混凝土結(jié)構(gòu)耐久性的損傷研究[J];混凝土;2008年08期
9 劉惠蘭,黃艷,韓云屏;環(huán)境水對砂漿、混凝土的侵蝕性研究[J];混凝土與水泥制品;1997年06期
10 賀鴻珠,史美倫,陳志源;粉煤灰對地鐵雜散電流的抑制作用[J];混凝土與水泥制品;2001年01期
相關(guān)博士學位論文 前1條
1 關(guān)博文;交變荷載與硫酸鹽腐蝕作用下水泥混凝土疲勞損傷機制[D];長安大學;2012年
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