摘 要：研究了在不同尾矿砂替代率、纤维掺量和纤维长度对尾矿砂水泥基复合材料的增强和增韧作用。试验验结果表明，尾矿砂替代PVA水泥基复合材料中的细骨料工作性能和基本力学性能稳定，制备工艺满足要求；在纤维长度和掺量一定时，尾矿砂替代率为50%效果较好；纤维长度为12mm，掺量为26kg/m3时，PVA可以使尾矿砂PVA水泥基复合材料的延性明显增强。 Abstract: The different replacement ratio of tailing sand to cement as well as the reinforced and toughening roles of content and length of fiber in the cement-based composites with tailings sand are studied. The test results show that using tailing sand to replace PVA cement-based composites as fine aggregate, the workability and basic mechanics performance of the mixture is stable and can meet the requirements of the preparation technology; when the replacement ratio of tailing sand is 50% and the length and content of PVA fiber are fixed, the properties of the mixture are much better; when the length of PVA fiber is 12mm and the content of PVA fiber is 26kg/m3, the ductility of the tailing sand and PVA cement-based composites with tailing sand can significantly enhance.

摘 要：为研究石英岩煤矸石人工砂替代河砂配制砌筑砂浆的可行性，对陕北某煤矿所排出石英岩煤矸石破碎制得人工砂替代河砂配制砌筑砂浆的拌合物性能和力学性能进行试验研究。研究结果表明，煤矸石破碎过程中产生的细粉可以作为惰性填料掺入砂浆；掺入水泥用量20%的煤矸石细粉可改善砂浆拌合物和易性，同时可提高砂浆的立方体抗压强度和轴心抗压强度；用50%石英岩煤矸石人工砂替代河砂时，砂浆分层度最小，70%替代河砂时轴心抗压强度和弹性模量均达到最小值。 Abstract：The workability and mechanical behaviors of the mortar prepared with artificial sand made by breaking quartzite gangue from coal mine in Northern of Shaanxi is studied in order to investigate the feasibility of masonry mortar prepared with quartzite gangue (artificial sand) broken to replace the river sand. The study shows that the coal gangue powder produced by the fragmentation technology can be added into the mortar as insert filler; the workability of the fresh mortar can be improved by mixing with coal gangue powder at 20% of the cement content, while the compressive strength and axial compressive strength of the cube specimens are also increased. The coursing degree of mortar is minimum when 50% of the quartzite gangue replaces river sand, and the axial compressive strength and elastic modulus of the specimens can be minimum value when the replacement ratio of the quartzite gangue is 70%.

摘 要：拉法基瑞安重庆永川水泥生产线项目地质状况及施工条件比较复杂，在部分基础和垫层以下填充混凝土工程施工过程中出现了裂缝现象。分析了本工程出现裂缝的原因，阐述了使裂缝得到有效控制所采取的一系列措施。 Abstract： Because the geological condition and construction condition of Lafarge Chongqing Yongchuan cement production line project are complicated, some parts such as the part foundation or under the cushion layer had the cracks during the construction process of filling the concrete. For solving the problem, the causes of cracks are analyzed, and some measures for controlling the cracks are put forward.

摘 要：以河南某电厂180m钢筋混凝土结构烟囱施工过程为例，根据高耸烟囱结构特点，筒体采用无井架液压滑模施工工艺，为了降低工程事故，滑模操作平台采取整体拆除法，缩短了拆模时高空作业时间，克服了传统工艺分散拆模法的诸多风险和安全隐患。 Abstract: Taking the construction process of 180m reinforced concrete structure chimney of a power plant in Henan as an example and according to the characteristics of high chimney structure, the construction technology of hydraulic sliding formwork without headframe is chosen for the barrel construction. The sliding operation platform uses the overall demolition method in order to reduce engineering accidents. The method can shorten the aerial work time when the formwork is removed and overcome many risk and hidden danger of disperse mould removal method.

摘 要：结合抚顺皇家海洋世界跨线桥110m提篮式双曲钢管混凝土拱施工，介绍了顶升法泵送混凝土的施工和质量控制方法；并依据混凝土顶升的施工原理、顶升压力，分析了影响因素，改进了混凝土配合比；采取设置止回装置和排气溢流孔等方法，解决了钢管拱混凝土一次顶升的难题。 Abstract: Combining with the construction of the Royal Fushun ocean world overpass 110m double steel pipe concrete vault with basket type, the lift-up pump concrete construction and a quality control method of concrete are introduced. And according to the principles of concrete lift-up construction, lift-up pressure, some relative influence factors are analyzed and mix proportion of concrete is optimized; in addition, using the methods of setting non-return devices, exhaust overflow orifice, etc. can solve the once lift-up problem of steel tube arch concrete.

摘 要：通过结构计算分析了波形钢腹板组合箱梁桥横梁，针对横梁裂缝宽度超限、承载能力不足的问题，提出增设预应力钢束和增加特殊支座及预应力钢束的两个加固方案。对横梁加固方案进行了计算，分析加固横梁应力和抗裂性指标，分析结果表明，横梁加固方案二从根本上解决了横梁存在的问题。最后从计算结果、施工难度与工作量、钢束锚固等因素考虑，选取了增加特殊支座及预应力钢束的横梁加固方案。 Abstract: The beams of composite box girder bridges with corrugated steel web are analyzed by the structure calculation, and according to crack width overrun of the beam and insufficient bearing capacity, the reinforcement schemes of adding prestressed steel beam or adding special bearings and prestressed steel beam are put forward. Meanwhile, the reinforcement schemes for the beam are calculated, and the indexes of stress and crack resistance of the reinforcement beams are analyzed. The results show that the reinforcement schemeⅡ can radically solve all the problems of the beam. In addition, considering some factors such as the calculation results, construction difficulty, workload, steel beam anchorage, it’s suggested that the schemes of adding special bearings and prestressed steel beam should be selected.