本文選題：橋梁工程　切入點(diǎn)：混凝土　出處：《長安大學(xué)學(xué)報(自然科學(xué)版)》2017年03期

【摘要】：為了建立細(xì)觀隨機(jī)混凝土模型,將混凝土假定為由粗骨料和水泥砂漿組成的兩相復(fù)合材料,根據(jù)常用骨料的類型,將其分別假定為圓形、橢圓形、凸多邊形3種截面形狀,分別給出了二維卵石和碎石骨料的隨機(jī)投放算法,并利用MATLAB軟件編制了相應(yīng)程序,從而實(shí)現(xiàn)了細(xì)觀層次隨機(jī)混凝土模型的數(shù)值計算。為了使MATLAB生成的隨機(jī)混凝土模型能被有限元程序調(diào)用,并對混凝土物理力學(xué)性能作進(jìn)一步分析,研制了fig2dxf程序,將MATLAB中圖形文件轉(zhuǎn)換為.dxf格式,實(shí)現(xiàn)了隨機(jī)骨料模型與有限元軟件的無縫對接。研究結(jié)果表明:建立的隨機(jī)骨料模型既滿足骨料體積的等效性,又保證了骨料粒徑的隨機(jī)性,骨料含量水平較高;圓形和橢圓形隨機(jī)混合骨料更符合隨機(jī)性要求和實(shí)際情況;凸多邊形骨料隨機(jī)投放算法簡單,同時巧妙地消除了多邊形骨料的尖角;利用常用的有限元軟件ANSYS等對生成的隨機(jī)骨料進(jìn)行網(wǎng)格劃分的效果較好;用建立的模型生成標(biāo)準(zhǔn)混凝土試件符合規(guī)范要求,并能滿足有限元細(xì)觀分析的需要,為進(jìn)一步研究混凝土細(xì)觀物理、力學(xué)性能提供了可靠基礎(chǔ)。
[Abstract]:In order to establish a meso-random concrete model, the concrete is assumed to be a two-phase composite composed of coarse aggregate and cement mortar. According to the types of aggregates commonly used, they are assumed to be circular, elliptical and convex polygon respectively. Two dimensional pebbles and gravel aggregates are randomly dropped, and the corresponding programs are compiled by using MATLAB software. In order to make the stochastic concrete model generated by MATLAB can be called by finite element program and further analyze the physical and mechanical properties of concrete, a fig2dxf program is developed. The graphic file in MATLAB is converted to .dxf format, and the random aggregate model is seamlessly connected with the finite element software. The results show that the established random aggregate model not only meets the equivalence of aggregate volume, but also ensures the randomness of aggregate size. The content of aggregate is high, the random mixture of round and elliptical aggregate is more suitable for randomness and actual situation, the random dropping algorithm of convex polygon aggregate is simple, and the sharp angle of polygon aggregate is skillfully eliminated. Using the commonly used finite element software ANSYS and so on to mesh the generated random aggregate, the standard concrete specimen generated by the established model meets the requirements of the code and can meet the needs of the finite element mesoscopic analysis. It provides a reliable basis for further study of the meso physical and mechanical properties of concrete.
【作者單位】： 長安大學(xué)舊橋檢測與加固技術(shù)交通行業(yè)重點(diǎn)實(shí)驗(yàn)室;中交第一公路勘察設(shè)計研究院有限公司;
【基金】：交通運(yùn)輸部應(yīng)用基礎(chǔ)研究項(xiàng)目(2013 319 812 100) 國家自然科學(xué)基金項(xiàng)目(51508027)
【分類號】：TU528
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本文編號：1681528