發(fā)布時(shí)間：2018-08-06 16:45

【摘要】：中國正處于建設(shè)高峰期，每年產(chǎn)生大量廢棄混凝土；另外公路建設(shè)特別是路面建設(shè)需要消耗大量優(yōu)質(zhì)碎石。在路面建設(shè)中利用部分建筑垃圾不但能夠緩解天然集料緊缺的情況，同時(shí)也有助于解決建筑垃圾的處理問題，起到一箭雙雕的作用。本論文針對廢舊混凝土再生集料及在水泥穩(wěn)定基層中的應(yīng)用展開研究，從再生骨料的制備、強(qiáng)化及性能評(píng)價(jià)，水泥穩(wěn)定再生集料基層材料的組成設(shè)計(jì)方法、性能評(píng)價(jià)及強(qiáng)度標(biāo)準(zhǔn)展開研究，，不僅能為全面推廣再生集料的應(yīng)用提供理論支撐，而且會(huì)取得良好的經(jīng)濟(jì)效益、社會(huì)效益和環(huán)境效益。 論文首先測試了再生集料的吸水率、壓碎值、密度等物理力學(xué)性能，并借助SEM圖像觀測其微觀結(jié)構(gòu)，結(jié)果表明再生骨料存在空隙和微裂縫，導(dǎo)致其吸水率和壓碎值偏高、密度和強(qiáng)度偏低；為提高再生集料的技術(shù)性能，需要采用強(qiáng)化措施提高其性能。 其次，利用洛杉磯磨耗儀和化學(xué)試劑分別對再生集料進(jìn)行物理和化學(xué)強(qiáng)化，通過測試強(qiáng)化后的再生集料的物理力學(xué)指標(biāo)來評(píng)價(jià)強(qiáng)化效果。10個(gè)鋼球、轉(zhuǎn)動(dòng)400圈可以使再生集料的壓碎值降低到22.9%、吸水率降低到4.2%；加入活化劑后，再生集料的大部分孔隙被有效封堵，導(dǎo)致降低再生集料的壓碎值和吸水率；有機(jī)硅樹脂的活化效果優(yōu)于鈦酸酯偶聯(lián)劑及硅烷偶聯(lián)劑，其最佳劑量為3.77%；經(jīng)最佳劑量的有機(jī)硅樹脂活化后的再生集料的壓碎值降低到19%、吸水率降低到2%以下。推薦了化學(xué)活化的工藝，包括拌合時(shí)間、養(yǎng)護(hù)時(shí)間與溫度。 再次，配置再生集料摻配率為0%、30%、60%、100%的水泥穩(wěn)定再生集料，按水泥劑量為4%和5%成型各種試件，測試水泥穩(wěn)定再生集料的壓實(shí)特性、強(qiáng)度特性、剛度特性、抗凍性和收縮特性，并分析其影響因素，結(jié)果表明水泥穩(wěn)定再生集料滿足道路使用的要求。 最后，采用Bisar軟件計(jì)算高速公路和二級(jí)公路兩種典型路面結(jié)構(gòu)的力學(xué)響應(yīng)，并推薦水泥穩(wěn)定再生集料基層的合理模量，并結(jié)合水泥穩(wěn)定再生集料90d模量和7d強(qiáng)度的關(guān)系模型，推薦了水泥穩(wěn)定再生集料的7d強(qiáng)度設(shè)計(jì)標(biāo)準(zhǔn)：二級(jí)公路為2.5~3.178MPa、高速公路為3.5~3.938MPa。
[Abstract]:China is in the peak of construction, producing a large number of waste concrete every year; in addition, highway construction, especially pavement construction, needs to consume a large amount of high-quality gravel. The use of some construction garbage in pavement construction can not only alleviate the shortage of natural aggregate, but also help to solve the problem of disposal of construction waste, and play a role of killing two birds with one stone. In this paper, the recycled aggregate of waste concrete and its application in cement stabilized base are studied, including the preparation, strengthening and performance evaluation of recycled aggregate, and the composition design method of cement stabilized recycled aggregate base material. The research on performance evaluation and strength standard can not only provide theoretical support for the comprehensive application of recycled aggregate, but also obtain good economic, social and environmental benefits. Firstly, the physical and mechanical properties of recycled aggregate, such as water absorption, crushing value, density and so on, are tested. The microstructure of recycled aggregate is observed by means of SEM image. The results show that there are voids and micro-cracks in recycled aggregate, which results in high water absorption and crushing value. In order to improve the technical performance of recycled aggregate, strengthening measures should be adopted to improve its performance. Secondly, the physical and chemical strengthening of recycled aggregate was carried out by means of Los Angeles wear tester and chemical reagent respectively, and 10 steel balls were evaluated by testing the physical and mechanical indexes of the reinforced recycled aggregate. Rotation of 400 circles can reduce the crushing value of recycled aggregate to 22.9 and the water absorption to 4.2. After adding activator, most of the pores of recycled aggregate are effectively blocked, which leads to the reduction of crushing value and water absorption of recycled aggregate. The activation effect of organosilicone resin is better than that of titanate coupling agent and silane coupling agent, and the optimum dosage is 3.77, and the crushing value of regenerated aggregate is reduced to 19%, and the water absorption is reduced to less than 2%. The process of chemical activation is recommended, including mixing time, curing time and temperature. Thirdly, the cement stabilized recycled aggregates with a ratio of 0% to 30% and 100% of the recycled aggregate are allocated to form various specimens according to the cement dosage of 4% and 5%. The compaction, strength, stiffness, frost resistance and shrinkage characteristics of the cement stabilized recycled aggregate are tested. The results show that cement stabilized recycled aggregate meets the requirements of road use. Finally, the mechanical response of two typical pavement structures of expressway and second-grade highway is calculated by Bisar software, and the reasonable modulus of cement stabilized recycled aggregate base is recommended, and the relationship model between 90 d modulus and 7 d strength of cement stabilized recycled aggregate is proposed. The design standard of 7 d strength of cement stabilized recycled aggregate is recommended as follows: the second grade highway is 2.5 ~ 3.178 MPa, and the expressway is 3.5 ~ 3.938 MPa.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：U414

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 仲文亮;呂松濤;;不同齡期對水穩(wěn)基層強(qiáng)度與模量及其內(nèi)在聯(lián)系的影響研究[J];中外公路;2014年01期

2 李惠強(qiáng),杜婷,吳賢國;建筑垃圾資源化循環(huán)再生骨料混凝土研究[J];華中科技大學(xué)學(xué)報(bào);2001年06期

3 屈志中;鋼筋混凝土破壞及其利用技術(shù)的新動(dòng)向[J];建筑技術(shù);2001年02期

4 肖建莊,孫振平,李佳彬,顧志強(qiáng);廢棄混凝土破碎及再生工藝研究[J];建筑技術(shù);2005年02期

本文編號(hào)：2168339