- 摘 要
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（1 內(nèi)蒙古農(nóng)業(yè)大學(xué)水利與土木建筑工程學(xué)院，呼和浩特 010018；2內(nèi)蒙古建筑職業(yè)技術(shù)學(xué)院經(jīng)濟管理學(xué)院，呼和浩特 010070）
［摘要］為研究水泥基混凝土孔隙結(jié)構(gòu)對其抗壓強度的影響，通過其孔隙結(jié)構(gòu)參數(shù)預(yù)測抗壓強度。對C30混凝土進行宏觀抗壓強度試驗、微觀電子顯微鏡試驗（SEM）、微觀核磁共振試驗（NMR），研究混凝土孔隙結(jié)構(gòu)對混凝土抗壓強度的影響，利用灰色關(guān)聯(lián)熵分析方法建立抗壓強度與孔隙結(jié)構(gòu)關(guān)系的數(shù)學(xué)基礎(chǔ)模型。試驗結(jié)果表明：隨著養(yǎng)護齡期的增長，有害孔與多害孔占比逐漸減少，無害孔占比逐漸增加；混凝土的橫向弛豫時間T2譜呈現(xiàn)“大峰帶小峰”的構(gòu)造，譜面積隨養(yǎng)護齡期增長而減?。粚箟簭姸扔绊懽畲蟮膬煞N因素為束縛流體飽和度（IFS）和半徑大于10μm的孔隙占比，其灰熵關(guān)聯(lián)度分別為0.997 1和0.997 2；以抗壓強度與束縛流體飽和度（IFS）及半徑大于10μm的孔隙占比建立GM（1，3）模型，模型預(yù)測值與試驗值的平均相對誤差為5.11%，并利用強度預(yù)測模型對多處混凝土的孔隙結(jié)構(gòu)參數(shù)進行強度模擬，相對誤差最小為0.4%，最大為7.75%，表明預(yù)測模型可以作為混凝土強度檢測的公式依據(jù)。
［關(guān)鍵詞］水泥基混凝土；孔隙結(jié)構(gòu)；演變特征；抗壓強度；灰熵
中圖分類號：TU502+.6文獻標識碼：A文章編號：1002-848X(2020)24-0116-08
Grey relational entropy analysis of influence of cement-based concrete pore structure evolution characteristics on strength
LI Hao1, GUO Haolong1, ZHANG Yuan2
（1 College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China; 2 School of Economic Management, Inner Mongolia Technical College of Construction, Hohhot 010070, China）
Abstract:In order to study the influence of the pore structure of cement-based concrete on its compressive strength, the compressive strength was predicted through its pore structure parameters. Macroscopic compressive strength test, scanning electron microscope test (SEM) and microscopic nuclear magnetic resonance test (NMR) were conducted of C30 concrete to study the influence of concrete pore structure on concrete compressive strength, and the compressive strength and the grey relational entropy analysis method was used to establish the mathematical basic model of the relationship between compressive strength and pore structure. The test results show that with the increase of the curing age, the proportion of harmful holes gradually decreases, and the proportion of harmless holes gradually increases; the transverse relaxation time T2 graph of concrete shows a structure of “large peaks with small peaks”, and the spectrum area decreases with the increase of the curing age; the two factors that have the greatest impact on the compressive strength are the bound fluid saturation (IFS) and the ratio of pores with a diameter greater than 10μm, and the gray entropy correlation is 0.997 1 and 0.997 2 respectively. The GM(1,3) model was established based on the compressive strength and the infinite fluid saturation (IFS) and the ratio of pores with a diameter greater than 10μm. The average relative error between the predicted value of the model and the experimental value was 5.11%, and the strength prediction model was used to simulate the strength of the pore structure parameters of the concrete. The minimum relative error was 0.4% and the maximum was 7.75%, indicating that the prediction model can be used as a formula basis for concrete strength testing.
Keywords:cement-based concrete; pore structure; evolution characteristic; compressive strength; gray entropy
*內(nèi)蒙古教育廳重點項目（NJZZ18044），內(nèi)蒙古農(nóng)業(yè)大學(xué)博士啟動費（RZ1900002013）。
作者簡介：李昊，博士，副教授，Email：hao.li@imau.edu.cn。
