本文關(guān)鍵詞： 混雜纖維 活性粉末混凝土 力學(xué)性能 抗?jié)B性 SEM　出處：《內(nèi)蒙古工業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著科技不斷進(jìn)步,高強(qiáng)混凝土和纖維混凝土有了良好發(fā)展�；钚苑勰┗炷�(RPC)作為高強(qiáng)混凝土和纖維混凝土的完美結(jié)合應(yīng)運(yùn)而生。RPC因其具有良好的力學(xué)性能和耐久性能,而被廣泛使用在橋梁、隧道工程中。由于傳統(tǒng)RPC中添加鋼纖維具有易銹蝕、造價(jià)高等缺點(diǎn),因此本論文利用玄武巖纖維替代鋼纖維,并與聚丙烯纖維混摻,配制成混雜纖維活性粉末混凝土(HFRPC),研究了HFRPC的力學(xué)性能和抗?jié)B性能。具體工作如下:1通過(guò)正交試驗(yàn)進(jìn)行HFRPC配合比設(shè)計(jì),選取水膠比、砂膠比、水泥/粉煤灰、減水劑、玄武巖纖維摻量為因素,根據(jù)試驗(yàn)精度要求設(shè)定相應(yīng)的水平。并依據(jù)抗壓強(qiáng)度和抗折強(qiáng)度,通過(guò)極差法得出RPC基體的最優(yōu)配比。2.在基體最優(yōu)配比基礎(chǔ)上,研究混摻玄武巖纖維和聚丙烯纖維、單摻玄武巖纖維、單摻聚丙烯纖維各自的力學(xué)性能。當(dāng)高彈性模量纖維摻量較少時(shí),低彈性模量纖維摻量的增加不會(huì)引起強(qiáng)度的大幅增長(zhǎng)。在抗壓強(qiáng)度增長(zhǎng)上,高彈性模量纖維起到主導(dǎo)作用。在抗折強(qiáng)度增長(zhǎng)上,低彈性模量纖維單位體積數(shù)量較多,纖維均勻分布在基體內(nèi)部,有效阻礙微裂縫的發(fā)展,細(xì)小的纖維還能跨越裂縫,繼續(xù)承擔(dān)剪力,使基體的抗折強(qiáng)度增長(zhǎng)明顯。3.在標(biāo)準(zhǔn)養(yǎng)護(hù)條件和90℃熱水養(yǎng)護(hù)條件下分別對(duì)混雜纖維RPC試件的抗壓強(qiáng)度進(jìn)行研究,得出標(biāo)準(zhǔn)養(yǎng)護(hù)條件下混雜纖維RPC試件在28d強(qiáng)度達(dá)到最大,而90℃熱水養(yǎng)護(hù)條件下混雜纖維RPC試件7d就能達(dá)到最終強(qiáng)度的95%以上。90℃熱水養(yǎng)護(hù)可以縮短養(yǎng)護(hù)時(shí)間,為今后RPC的大規(guī)模普及和實(shí)現(xiàn)現(xiàn)場(chǎng)澆筑奠定一定的理論基礎(chǔ)。4.選取混雜玄武巖和聚丙烯纖維、單摻玄武巖纖維、單摻聚丙烯纖維活性粉末混凝土,利用電通量法進(jìn)行抗?jié)B性能試驗(yàn),研究其抗?jié)B性能的優(yōu)劣性。得出混雜纖維RPC的抗?jié)B性能不及單摻纖維RPC的抗?jié)B性能,其中單摻聚丙烯纖維RPC的抗?jié)B性能最佳。5.通過(guò)電鏡掃描,從微觀角度研究影響RPC抗?jié)B性能好壞的因素,并通過(guò)對(duì)RPC滲前、滲后SEM圖片的對(duì)比,利用微觀形態(tài)對(duì)混雜纖維RPC和單摻纖維RPC的抗?jié)B性能優(yōu)劣進(jìn)行論證。
[Abstract]:With the progress of science and technology. High strength concrete and fiber reinforced concrete have developed well. Reactive Powder concrete (RPC). As the perfect combination of high strength concrete and fiber concrete, RPC has good mechanical properties and durability. It is widely used in bridge and tunnel engineering. Because the steel fiber added in traditional RPC has the disadvantages of easy corrosion and high cost, basalt fiber is used to replace steel fiber and mixed with polypropylene fiber in this paper. The mechanical properties and impermeability of hybrid fiber reactive powder concrete (HFRPC) were studied in this paper. The results are as follows: 1. The design of HFRPC mixture ratio is carried out by orthogonal test. The water / binder ratio, sand / binder ratio, cement / fly ash, water reducer, basalt fiber are selected as factors, and the corresponding level is set according to the requirement of test precision, and according to the compressive strength and flexural strength. The optimum ratio of RPC matrix was obtained by the range method. Based on the optimum ratio of matrix, the mixed basalt fiber and polypropylene fiber were studied, and the basalt fiber was only doped. When the content of high elastic modulus fiber is small, the increase of low elastic modulus fiber content will not cause the strength to increase substantially. The high elastic modulus fiber plays a leading role. In the increase of flexural strength, the low elastic modulus fiber has more unit volume, and the fiber distributes evenly in the matrix, which effectively hinders the development of micro-cracks. Fine fibers can also cross cracks and continue to bear shear forces. The flexural strength of the matrix increased obviously. 3. The compressive strength of hybrid fiber RPC specimens was studied under standard curing conditions and 90 鈩，

本文編號(hào)：1470464