研究了超细粉煤灰单掺、硅灰-超细粉煤灰复掺对复合水泥粉体压实体空隙率、硬化浆体孔结构和抗压强度的影响规律;同时,研究了砂率对砂石骨料混合体系空隙率的影响规律;并结合两者研究内容开展超高强混凝土配制研究。结果表明:超细粉煤灰30%时,超细粉煤灰-水泥复合粉体压实体空隙率最小;硅灰在0~10%范围内等质量取代超细粉煤灰,可进一步降低硅灰-超细粉煤灰-水泥复合粉体压实体空隙率,硅灰掺量8%时,复合水泥压实体空隙率最低;复合水泥粉体压实体空隙率越小,复合水泥硬化浆体孔隙率越小、有害孔含量越少、28、60d抗压强度越高;砂率45%时,砂石骨料混合体系空隙率最低;通过调整胶凝材料粉体堆积空隙率和砂石骨料混合空隙率,可配制出28d抗压强度≥135MPa,60d抗压强度可达到≥145MPa的超高强自密实混凝土。

The effects of UFA single doped and silica fume-UFA co-doped on composite cement powder pressure entities porosity,hard-ened paste pore structure,hardened paste compressive strength are studied.The study of the influence of sand ratio on the voidage of aggre-gate.Experimental study on preparation of ultra high strength concrete according to the two research.The results showed that when the con-tent of ultra fine fly ash was 30%,UFA-Cement composite achieved the densest packing density.In the range of 0~10%,silica fume equal replace UFA can continue to reduce the pressure entities porosity of Silica fume-UFA-cement composite powder,when the content of silica fume was 8%,silica fume-UFA-cement composite achieved the densest packing density.When the compacting voidage value reaches mini-mum,the average pore radius and maximum pore radius of hardened cement paste reach the minimum values.In addition,the 28 d and 60 d compressive strength of composite cement paste was higher.when the sand r

为研究型煤制备工艺与性能之间的关系，以指导生产工艺优化，利用单偏光显微镜及数字图像处理技术对不同黏结剂添加量和成型压力下制备的型煤空隙总体特征，以及水平方向与垂直方向上空隙分布特征进行研究，深入分析了空隙直径、位置及定向程度等特征。研究结果表明：不同黏结剂添加量及成型压力制备的型煤中空隙率差别较大；型煤水平方向与垂直方向上空隙率不同，水平方向上空隙直径较为集中；型煤空隙分布不均匀，定向程度差；型煤空隙从表面到内部有增大趋势。

In order to study the relationship between briquette preparation technique and performances and guide the optimization of the production technique,a single polarized microscope and digital image processing technology were applied to two aspacts study,which the total void features and the horizontal and vertical void distribution features of the briquette prepared with different quality binder and differ-ent pressure,and to the deep analysis on the void diameter,location,orientation degree and other features.The study results showed that the void rate of the briquette prepared with different quality binder and different pressure would be have big difference.The horizontal and verti-cal void rates of the briquette would be different and the horizontal void diameter would be concentrated. The void distribution of the bri-quette would be inhomogeneous and the orientation degree would be poor.The void of briquette from the surface to the internal would be in an increasing tendency

为了评价室内成型试件与路面芯样抗车辙能力的差异,利用多轮车辙仪(RLWT)获取车辙变形量,从宏观角度研究室内成型试件与路面芯样的抗车辙能力;采用工业CT获取沥青混合料断面扫描图像,从细观角度探讨室内成型试件与路面芯样的粗集料颗粒与面空隙率沿深度方向的分布状况.结果表明:由于压实方式不同,两种试件的空隙率相差甚大,从而导致其抗车辙能力也有明显差异;路面芯样的粗集料颗粒与面空隙率在深度方向分布的均匀性较差;路面芯样的平均面空隙率及上端的面空隙率明显大于室内成型试件,从细观角度证明了宏观研究成果的准确性.

To evaluate the rutting resistance differences of indoor samples and pavement cores, Rotary Loaded Wheel Tester ( RLWT) was used to acquire rutting deformation, and rutting resistance of indoor samples and pavement cores was researched from the macro perspective. Industrial CT was utilized to obtain asphalt mixture sectional scanning images, the distribution along the depth direction of coarse aggregate particles and area porosity of indoor samples and pavement cores from the micro angle were explored. The results show that the air porosity of the two kinds of samples vary greatly due to the different manners of compaction, leading to the significant discrepancy in the capability of rutting resistance. The uniformity of the distribution along the depth of coarse aggregate particles and area porosity of pavement cores are poor, and the average area porosity and area porosity in the upper part of the pavement cores are obviously greater than those of indoor samples, which proves the accu

研究了导流介质尺寸对真空辅助树脂传递模塑(VARTM)工艺中树脂流动行为的影响,以及对复合材料制品中纤维分布和空隙率的影响。结果表明,随着导流介质尺寸的增加,树脂在增强体中的流动速度加快,并呈现指数加速趋势;制品中纤维体积含量呈现先减少后增大的趋势,并且以导流介质边界为纤维体积含量高低的分界线;复合材料制品的空隙率范围在3.86%~19.92%,空隙率呈现先增大后减小再加速增大的趋势。

Effects of the size of infusion media on resin flow behavior,fiber volume fraction distribution and void content in vacuum assisted resin transfer molding(VARTM) were studied.The results showed that with the increase of infusion media size, the resin flow rate increased exponentially;the fiber volume fraction showed a tendency to increase after the first decrease,and the infusion media boundary was just the high and low fiber volume fraction line;the void content increased first and then decreased and increased tremendously at last,varied from 3.86% to 19.92%.

目前,贝雷法在密级配沥青混合料配合比设计中已得到了广泛的应用,但在开级配大空隙沥青混合料配合比设计中的应用还不多见。结合温拌半柔线复合路面基体沥青混合料特点,在贝雷法基础上利用预留空隙率进行了整体级配的设计,并通过路用性能检验来评价其应用效果。结果表明,通过贝雷法设计的基体沥青混合料空隙率大小合适,具有良好的路用性能。

Bailey method is commonly applied in proportion design of asphalt mixture with dense gradation;but rarely used in proportion design of asphalt mixture with open gradation. In combination with characteristics of warm mix semi flexible compound pavement asphalt mixture, its general proportion was designed by using Bailey method, and its application effect was evaluated through road performance test. The results show that the porosity of the asphalt mixture designed by Bailey method is appropriate and the road performance is satisfied.