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  本文選題：有機-無機復(fù)合　切入點：內(nèi)養(yǎng)護材料　出處：《武漢理工大學(xué)》2013年博士論文　論文類型：學(xué)位論文

【摘要】：高強高性能混凝土因水膠比低、膠材用量大、過量使用超細礦物摻合料等，而普遍存在早期開裂問題。通過預(yù)先內(nèi)置的吸水性材料適時釋水，提高混凝土內(nèi)部相對濕度，降低其自收縮的內(nèi)養(yǎng)護(Internal curing)已成為解決混凝土收縮裂縫的有效方法。本文依托國家自然科學(xué)基金(51202039)，，設(shè)計、合成了新型聚合物內(nèi)養(yǎng)護材料，圍繞材料的組成、結(jié)構(gòu)、性能開展了研究與工程應(yīng)用，取得了如下創(chuàng)新成果： 針對離子型聚合物堿性環(huán)境下吸水倍率低且失水導(dǎo)致工作性能和強度劣化，以及非離子型聚合物吸水倍率低導(dǎo)致混凝土后期內(nèi)養(yǎng)護不足的問題，提出了“高吸水-穩(wěn)定儲水-可控釋水”內(nèi)養(yǎng)護材料的設(shè)計方法。以木薯淀粉、丙烯酰胺（AM）、2-丙烯酰胺-2-甲基丙磺酸（AMPS）為主要原料，合成了吸水倍率達210~287、保水率80%以上、負壓釋水率75%以上的陰-非離子型聚合物內(nèi)養(yǎng)護材料(AN-ICA)。運用FT-IR、SEM和13C NMR等表征了其組成、形貌和結(jié)構(gòu)特征，系統(tǒng)研究了其吸水-儲水性能等與組成、網(wǎng)絡(luò)結(jié)構(gòu)之間關(guān)系。研究表明，AN-ICA淀粉主鏈上同時成功接枝了單體AM和AMPS，并形成了連續(xù)、多孔、三維條帶狀網(wǎng)絡(luò)結(jié)構(gòu)。該結(jié)構(gòu)具有足夠吸水空間并具有良好彈性和伸展能力，在水中溶脹而不溶解，從而提高了AN-ICA吸液能力；親水性基團-SO3H、-CONH2提供了聚合物吸液動力，并降低了混凝土中孔溶液同離子效應(yīng)使聚合物網(wǎng)絡(luò)收縮釋水，提高了其在堿性溶液中儲水穩(wěn)定性。 提出了在AN-ICA網(wǎng)絡(luò)結(jié)構(gòu)中復(fù)合剛性無機Si-O網(wǎng)絡(luò)，限制柔性陰-非離子型聚合物網(wǎng)絡(luò)結(jié)構(gòu)在堿性環(huán)境下的收縮行為，進一步提高內(nèi)養(yǎng)護材料的儲水穩(wěn)定性-釋水可控性的技術(shù)思路。制備的有機-無機復(fù)合內(nèi)養(yǎng)護材料(OIM-ICA)吸水倍率達188~270、保水率85%以上、釋水率80%以上。SEM-EDS分析表明OIM-ICA具有復(fù)合交聯(lián)網(wǎng)絡(luò)結(jié)構(gòu)。系統(tǒng)研究了合成工藝對吸水-儲水-釋水性能的影響，確定了原料配比及工藝參數(shù)：水玻璃8%~12%、交聯(lián)劑0.12%~0.18%、單體滴加時間1.5~2.5h、反應(yīng)溫度60~70℃。 系統(tǒng)研究了OIM-ICA摻量、細度、水膠比等因素對混凝土早期收縮影響，結(jié)果表明，隨摻量增加、粒徑減小及水膠比降低，混凝土內(nèi)部相對濕度降幅減小，早期自收縮顯著降低。OIM-ICA摻量為膠凝材料的0.07%時，摻15%粉煤灰、水灰比0.35的C50混凝土7d自收縮可降低120με以上；OIM-ICA內(nèi)養(yǎng)護作用減小了對自收縮貢獻最大的9~50nm毛細孔數(shù)量。基于毛細張力理論，引入內(nèi)養(yǎng)護水化因子和內(nèi)養(yǎng)護體積彈性模量因子，建立了OIM-ICA摻量、細度、水膠比與混凝土自收縮關(guān)系模型。 研究了OIM-ICA對膠凝漿體水化及混凝土力學(xué)性能、耐久性能等的影響規(guī)律。隨OIM-ICA摻量增加，膠凝漿體水化速率和放熱量降低，混凝土早期抗壓強度降低，后期與未摻OIM-ICA強度相近，后期抗氯離子滲透性能、抗凍性能、抗硫酸鹽侵蝕性能和抗碳化性能均提高。其影響機理為：早期膠凝漿體水化受OIM-ICA抑制并占據(jù)較大空間，提高了孔隙率，導(dǎo)致混凝土早期強度降低；后期OIM-ICA釋水內(nèi)養(yǎng)護作用使膠凝漿體水化程度提高，9~50nm毛細孔數(shù)量降低，水化產(chǎn)物在OIM-ICA周圍形成了能夠分散壓應(yīng)力的致密“拱殼結(jié)構(gòu)”，從而提高了混凝土后期強度和抗凍性，并有效阻止了Cl-、SO42-、CO32-等有害離子在毛細孔中的遷移，提高了抗氯離子滲透性、抗硫酸鹽侵蝕性和抗碳化性。 根據(jù)本文提出的內(nèi)養(yǎng)護材料設(shè)計方法和合成工藝，設(shè)計了年產(chǎn)2萬噸工業(yè)化生產(chǎn)線，批量生產(chǎn)了內(nèi)養(yǎng)護材料，并進行了工程應(yīng)用。結(jié)果表明摻入OIM-ICA提高了混凝土抗裂性能，有效解決了工程裂縫問題。
[Abstract]:High strength and high performance concrete with low water binder ratio, cement amount, excessive use of superfine mineral admixture, and the common problems of early cracking. Through the absorption of the pre built timely release of water, improve the internal relative humidity of concrete, reduce its self curing shrinkage (Internal curing) has become an effective method to solve concrete shrinkage crack. Based on the National Natural Science Fund (51202039), design, new polymer curing materials were synthesized on the composition of the material, structure, performance research and engineering application, the main contributions are as follows:
Aiming at the low water absorbency and water loss result working performance and strength deterioration under alkaline environment and ionic polymer, a nonionic polymer water absorbent rate due to the low late in the curing of concrete problems, put forward the "high water - stable water - controlled release design method of water" curing materials. With cassava starch, acrylamide (AM, 2- -2-) acrylamide methyl propyl sulfonic acid (AMPS) as the main raw material, water absorbency of 210~287 was synthesized, the water retention rate above 80%, the negative pressure water release rate of more than 75% anionic nonionic polymer curing materials (AN-ICA). The use of FT-IR, SEM and 13C NMR characterized their composition, morphology the structure and characteristics of the system, the water absorbing and water storage performance and composition, the relationship between network structure. The research results show that the AN-ICA backbone and starch was successfully grafted monomer AM and AMPS, and the formation of a continuous, porous, three-dimensional banded structure of the network. The structure has enough water space and has good elasticity and stretch ability, swelling in water and dissolved, thus improving the AN-ICA absorption capacity; hydrophilic groups of -SO3H, -CONH2 provides power and reduce the absorption of polymer, concrete pore solution with ion effect of the polymer network contraction release water improves the alkaline the solution of water storage stability.
Based on the AN-ICA network structure in the composite rigid inorganic Si-O network, limit the flexibility of anionic nonionic polymer network structure in alkaline environment the shrinkage behavior, to further improve the technical ideas of water storage stability of internal curing materials in water release control. The preparation of organic-inorganic composite curing materials (OIM-ICA) water rate of 188~270, the water retention rate of more than 85%, water release rate of more than 80%.SEM-EDS analysis showed that the OIM-ICA composite has a crosslinked network structure. The system of synthesis technology on the impact of water - water - water release performance, determine the ratio of raw materials and process parameters of water glass 8%~12%, crosslinking agent 0.12%~0.18%, monomer dropping time 1.5~2.5h, the reaction temperature is 60~70 degrees Celsius.
The system of fineness OIM-ICA dosage, effects of water binder ratio, and other factors on the early shrinkage of concrete. The results showed that with the dosage increase, the decrease of particle size and water cement ratio decreased, decreasing the internal relative humidity of concrete, autogenous shrinkage significantly decreased the content of.OIM-ICA as cementitious materials 0.07%, containing 15% fly ash the water cement ratio of concrete, C50 7d 0.35 can reduce the self shrinkage of 120 mu epsilon above; OIM-ICA curing effect reduce the autogenous shrinkage of the largest contribution to the 9~50nm number of pores. The capillary tension theory based on the introduction of internal curing hydration factor and maintenance volume elastic modulus factor, established OIM-ICA content, fineness, water cement compared with the autogenous shrinkage of concrete model.
The effects of OIM-ICA on body hydration and mechanical properties of concrete cement slurry, influence of durability. With increasing OIM-ICA dosage, cement paste hydration rate and reduce heat, reduce the compressive strength of concrete early, late and close to UN doped OIM-ICA strength, resistance to chloride ion permeability of late frost resistance,, sulfate resistance and carbonization resistance were improved. The influence mechanism is: early cementitious paste hydration inhibition by OIM-ICA and occupy a larger space, improve the porosity, which leads to the decrease of the early strength of concrete; late OIM-ICA water release maintenance effect of cementitious paste hydration degree increases. The number of pores decreased 9~50nm in OIM-ICA, the hydration products formed around to disperse dense "stress arch shell structure, so as to improve the concrete strength and frost resistance, and effectively prevent the Cl-, SO42-, CO32- and other harmful ions in the hair The migration in the pores, improve the permeability resistance of chloride ion, sulfate resistance and carbonization resistance.
According to the internal curing material design method proposed in this paper and the synthesis process, designed annual production capacity of 20 thousand tons of industrial production line, the production of maintenance materials, and the engineering application. The results showed that the incorporation of OIM-ICA improves the crack resistance of concrete engineering crack, effectively solve the problem.

【學(xué)位授予單位】：武漢理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2013
【分類號】：TU528

【參考文獻】

相關(guān)期刊論文 前10條

1 李家和,歐進萍,孫文博;摻合料對高性能混凝土早期自收縮的影響[J];混凝土;2002年05期

2 張勇,丁慶軍,于發(fā)洲,胡曙光;輕集料混凝土的界面結(jié)構(gòu)研究[J];混凝土;2002年10期

3 梁詠寧,袁迎曙;超聲檢測混凝土硫酸鹽侵蝕的研究[J];混凝土;2004年08期

4 葉華,趙建青,張宇;吸水樹脂水泥基材料自養(yǎng)護外加劑的研究[J];華南理工大學(xué)學(xué)報(自然科學(xué)版);2003年11期

5 高美蓉;秦鴻根;龐超明;;高性能混凝土內(nèi)養(yǎng)護技術(shù)的研究現(xiàn)狀[J];混凝土與水泥制品;2009年03期

6 王德志;孟云芳;韓靜云;;超吸水聚合物內(nèi)養(yǎng)護對混凝土抗凍性的影響[J];混凝土與水泥制品;2010年01期

7 唐蜀忠,任皓,胡學(xué)軍,王強;N,N-二甲基乙基丙烯酰胺同丙烯酰胺共聚合的競聚率測定[J];江漢石油學(xué)院學(xué)報;1999年03期

8 許華勝,蔣正武;高性能混凝土中自身相對濕度變化與自收縮的研究[J];重慶建筑大學(xué)學(xué)報;2004年02期

9 姚曉;朱華;吳葉成;張敏;;均勻?qū)嶒炘O(shè)計在合成淀粉基高吸水性樹脂中的應(yīng)用[J];精細石油化工;2009年01期

10 李悅,談慕華,張雄,吳科如;混凝土的自收縮及其研究進展[J];建筑材料學(xué)報;2000年03期

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