本文關(guān)鍵詞： 混凝土 細(xì)觀非均質(zhì) 單元彈性模量 網(wǎng)格單元尺寸 模型尺寸 骨料級(jí)配　出處：《應(yīng)用基礎(chǔ)與工程科學(xué)學(xué)報(bào)》2017年02期 　論文類型：期刊論文

【摘要】：針對(duì)現(xiàn)有細(xì)觀力學(xué)模型無(wú)法反映模型尺寸和骨料級(jí)配對(duì)混凝土材料細(xì)觀非均質(zhì)影響的局限性,假定混凝土由骨料顆粒、砂漿基質(zhì)及界面過(guò)渡區(qū)組成,基于Voigt并聯(lián)模型對(duì)細(xì)觀單元材料力學(xué)性能進(jìn)行等效,建立反映混凝土細(xì)觀非均質(zhì)的等效模型.以Weibull分布為假設(shè)分布,探討四種骨料級(jí)配邊長(zhǎng)150-750mm細(xì)觀等效模型的網(wǎng)格單元尺寸,以單元彈性模量的非均質(zhì)分布表征材料的細(xì)觀非均質(zhì)性,探討混凝土材料細(xì)觀非均質(zhì)性與模型尺寸和骨料級(jí)配的相關(guān)關(guān)系,研究材料細(xì)觀非均質(zhì)對(duì)混凝土強(qiáng)度及破壞模式的影響機(jī)理.研究結(jié)果表明:相同骨料級(jí)配下,隨著模型尺寸的增加,網(wǎng)格單元尺寸增大,混凝土材料非均質(zhì)性減弱;相同模型尺寸下,隨著骨料級(jí)配的增大,網(wǎng)格單元尺寸略有增加,混凝土材料的細(xì)觀非均質(zhì)性增強(qiáng);材料細(xì)觀非均質(zhì)性增強(qiáng)時(shí),混凝土強(qiáng)度略有降低,損傷破壞區(qū)域分布廣泛.
[Abstract]:In view of the existing micromechanics model cannot reflect the size of model and the aggregate gradation limitation of concrete meso heterogeneity effect, by the assumption that the concrete aggregate particles, consisting of mortar matrix and interfacial transition zone, Voigt parallel model of meso element equivalent in mechanical properties of materials based on the established equivalent model of concrete meso heterogeneity. Based on Weibull distribution of grid cell size distribution hypothesis, four kinds of aggregate gradation side 150-750mm meso equivalent model, the meso heterogeneity of heterogeneous distribution of material elastic modulus of elements, to discuss the relationship between concrete meso heterogeneity and model size and aggregate gradation, microscopic mechanism of heterogeneous materials research the influence of concrete strength and failure mode. The results show that: the same aggregate gradation, along with the increase of model size, mesh size, The heterogeneity of weakened concrete materials; the same model size, with the increase of aggregate gradation, grid cell size increases slightly, the concrete material meso heterogeneity enhancement; meso heterogeneity increased, concrete strength decreased slightly, the damage zones are distributed widely.

【作者單位】： 防災(zāi)科技學(xué)院;北京工業(yè)大學(xué)城市與工程安全減災(zāi)教育部重點(diǎn)實(shí)驗(yàn)室;
【基金】：中國(guó)地震局教師科研基金項(xiàng)目(20120104) 國(guó)家自然科學(xué)基金項(xiàng)目(51408127)
【分類號(hào)】：TU528
【正文快照】： 混凝土是重要的建筑材料,廣泛應(yīng)用于房屋建筑、高壩、橋梁、海洋平臺(tái)、核電站、地基基礎(chǔ)等工業(yè)與民用建筑領(lǐng)域,由于結(jié)構(gòu)跨度和高度的增加,混凝土構(gòu)件尺寸越來(lái)越大、受力越來(lái)越復(fù)雜,對(duì)承載能力要求越來(lái)越高,迫切需要開展混凝土材料破壞機(jī)理、尺寸效應(yīng)等宏觀力學(xué)特性的深入研究.，

本文編號(hào)：1479547