摘 要：研究了Ⅱ级粉煤灰、再生砖粉和再生混凝土微粉的基本性能，对比了再生砖粉和再生混凝土微粉替代Ⅱ级粉煤灰对混凝土工作性和力学性能的影响；并通过改性剂改善混凝土坍损过大的问题，分析了改性剂影响混凝土力学性能的机理。研究结果表明，再生砖粉和再生混凝土微粉在一定细度条件下，其性能与Ⅱ级粉煤灰相当；缓凝剂、激发剂以及部分表面活性剂组成的改性剂对工作性和力学性能具有明显的改善作用；而水化铝硅酸钙对混凝土力学性能有较大的提高作用。 Abstract: The basic properties of the fly ash, recycled brick powder and recycled concrete powder are studied. The recycled brick powder and recycled concrete powder instead of fly ash in concrete preparation are compared. The influence on the working performance and mechanical properties are investigated. And by adding the modifier to improve the large concrete slump loss. The mechanism of change influence of modifiers on mechanical properties of concrete are analyzed. The results show that the performance of recycled brick powder and recycled concrete powder in certain fineness conditions is similar to fly ash. The retarder, activator and some surfactant composition modifier have obvious effect on the working performance and mechanical properties, the hydration calcium silicate aluminum can improve the mechanical properties of concrete obviously.

摘 要：采取正交试验法研究了再生骨料掺量、水胶比、骨料颗粒级配三个因素对透水混凝土的强度和透水性的影响。结果表明，最佳配比为：再生骨料掺量40%、水胶比0.25，再生骨料由50%粒径为4.75～9.5 mm的再生骨料和50%粒径为9.5～16 mm的再生骨料混合组成，在该配比下制得的透水混凝土透水系数为6.3 mm/s，抗压强度为23.1 MPa。 Abstract: Orthogonal text were adopted to study the effects of recycled aggregate content, W/B, aggregate particle size distribution on the strength and permeability of permeable concrete. The results show that the performance of permeable concrete is the best when the recycled aggregate content is 40%, the W/B is 0.25, and the amount of recycled aggregates of 4.75～9.5 mm and 9.5～16 mm is taking 50% part, respectively. The compressive strength and permcability coefficicnt of pervious concrete obtaied by the mix proportion is 23.1 MPa and 6.3 mm/s

摘 要：将经改性的高岭土尾矿与水晶废渣复合，等量取代水泥内掺到水泥基材料中，研究了掺入前后和不同掺量对水泥基材料的工作性、力学性能和体积稳定性的影响。并运用SEM等微观测试手段，探讨了其影响机理。结果表明，当改性高岭土尾矿和水晶废渣掺量为10%时，对水泥基材料的工作性影响不大，同时能够提高砂浆的强度和体积稳定性，优化水化产物和水泥基材料的孔结构。 Abstract: The effect of modified kaolin tailings blended with crystal residues on performance on cement-based material, where the content of kaolin tailings and crystal residues mixture are varied by weight, is investigated. SEM is used to study the mechanism. The slump, strength and shrinkage of mortar mixes containing six different mixtures are tested. The results show that the strength and shrinkage performance significantly increases with the incorporation of 10% kaolin tailings and 10% crystal residues, meanwhile, the mixtures have little effect on the slump of mortar. On the other hand, kaolin tailings and crystal residues mixtures improve the hydration products and the pore structure of cement-based materials.

摘 要：顶升自密实微膨胀钢管混凝土可有效结合钢管和混凝土的优势且施工速度快、简单方便，浇筑质量良好，因此，在高层建筑和桥梁工程中得到了广泛应用。本文以市政桥梁泵送顶升项目为背景，分析了顶升自密实微膨胀钢管混凝土的原材料选择、配合比设计以及施工控制要点。 Abstract: The self-compacting micro-expansion pumping concrete filled steel tube can effectively combine the advantages of steel tube and concrete, and the construction speed is fast, simple and convenient, and the pouring quality is good. Therefore, it has been widely used in high-rise buildings and bridge engineerings. Based on the municipal bridge of pumping lift-up project, the raw material selection, mix proportion design and construction control key points of self-compacting micro-expansion concrete filed steel tube are analyzed .

摘 要：为实现机制砂自密实混凝土在钢管拱中获得良好的应用，研究了机制砂自密实混凝土的最佳配合比，进行了现场模拟试验，并提出了施工技术要点。试验制备出初始坍落度大于270 mm、坍落扩展度大于700 mm、倒坍落度筒流出时间小于5 s、6 h内工作性基本无损失、具有一定补偿收缩性能的钢管拱机制砂自密实混凝土。现场模拟试验验证了机制砂自密实混凝土可以无死角填充有机玻璃管。此外，经良好的现场施工组织与控制、浇筑过程监控，使得钢管拱机制砂自密实混凝土在工程中成功应用。 Abstract: In order to achieve the better application of manufactured sand self-compacting concrete (MS-SCC) in steel pipe arch. The optimum mix ratio of MS-SCC was studied, field simulation tests were carried out and the key construction technologies were put forward. MS-SCC filled steel pipe arch was prepared with the properties such as initial slump more than 270 mm, slump flow above 700 mm, dropping time of concrete from inverted slump cone less than 5 s, 6 h slump zero-loss and shrinkage-compensating. Field simulation tests show that the MS-SCC can be completely filled with plexiglass pipes. By the good construction organization, control and perfusion process monitoring on-sit. MS-SCC can be applied in the steel pipe arch project successfully.

摘 要：压碎指标用于衡量石子在逐渐增加的荷载下抵抗压碎的能力，是评定石子在建筑工程中适用性的重要力学性能指标。针对石子压碎指标值测定试样制备过程存在的不足，设计并研制了一种普通混凝土用石子压碎指标值测定试样制备装置。通过自动化机电控制方式，利用PLC控制器来控制和驱动电机来完成整个试验样品制备过程，一定程度上可减少试验人员的体力劳动的工作量，也可减小因经验不足或操作水平低而产生试验数据误差概率 Abstract: The crushing index is used to measure the ability of gravel to resist crushing under increasing load, which is an important mechanical performance index for assessing the applicability of gravel in construction engineering. Aiming at the deficiency in the preparation process of the gravel crushing index values, a kind of specimen preparation device for the measuring of the crushed index values of regular concrete was designed and developed. By means of automatic electromechanical controlling, utilized PLC controller to control and drive the motors to complete the whole process of sample preparation, the workload of manual labor of the tester can be reduced to a certain extent. It can also reduce the error probability of experimental data due to lack of experience or low level of operation.