现浇植被混凝土细观孔隙结构分析及渗流模拟  

Mesoscale Pore Structure Analysis and Seepage Simulation of Cast-in-situ Vegetation Concrete

作　　者：刘婷婷 温福胜 赵村罡 范华峰 刘福胜[1] 张坤强[1] LIU Ting-ting;WEN Fu-sheng;ZHAO Cun-gang;FAN Hua-feng;LIU Fu-sheng;ZHANG Kun-qiang(College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Taian 271000, Shandong Province, China)

机构地区：[1]山东农业大学水利土木工程学院,山东泰安271000

出　　处：《中国农村水利水电》2020年第10期88-93,105,共7页China Rural Water and Hydropower

基　　金：国家科技支撑计划项目(2015BA07B05);山东省自然基金项目(ZR2018PEE027)。

摘　　要：以目标孔隙率24%,水胶比0.32,粗骨料粒径16~26 mm的现浇植被混凝土为研究对象,通过计算机断层(CT)扫描技术获取试件的序列图像,采用Image J软件从细观角度分析二维平面孔隙特征;采用Avizo软件重建孔隙三维细观模型,分析孔隙空间结构并进行单相渗流模拟。结果表明:孔隙直径、孔隙面积均呈单峰分布,孔隙大小比较均匀;孔隙形状接近一个正圆;平面孔隙率平均值与实测孔隙率相差不大;计盒维数法测得的分形维数表明孔隙具有较好的分形特征;三维孔隙空间分布范围与二维定量分析具有一致性;孔喉尺寸呈正态分布,表明孔隙间连通性良好;压力梯度分布及流线分布有利于分析植被混凝土的渗流机理,模拟结果与试验结果吻合较好,验证了重建的三维模型的可靠性。The cast-in-place vegetation concrete with a target porosity of 24%,water cement ratio of 0.32 and the coarse aggregate size of 16~26 mm is used as the research object.The sequence image of cast-in-place vegetation concrete is obtained by computer tomography(CT)scanning technology and the two-dimensional plane pore characteristics are analyzed from the mesosacle by the ImageJ software Avizo software is used to reconstruct the pore three-dimensional mesoscopic model,analyze the space structure of the pore and simulate the single-phase seepage flow.The results show that,the pore diameter and pore area are distributed in a single peak,and the pore size is relatively uniform.The pore shape is close to a perfect circle;the difference between the average value of plane porosity and the measured porosity is small.The fractal dimension measured by box counting method shows that pores have good fractal characteristics.The spatial distribution of three-dimensional pores is consistent with that of two-dimensional quantitative analysis.The pore throat size is normal distribution,indicating good connectivity between the pores.The distribution of pressure gradient and streamline are conducive to the analysis of the seepage mechanism of vegetation concrete.The results of seepage simulation and test are in good agreement,which verifies the reliability of the reconstructed 3D model.

关 键 词：现浇植被混凝土 CT扫描 孔隙特征 三维重建 渗流模拟 

分 类 号：TV431.4[水利工程—水工结构工程]