棒材对齐辊道及移钢系统的技术改造

针对棒材精整对齐量不足,切头去尾浪费大,弯钢现象严重的难题,采用将对齐辊道由原来的柱形辊改为槽形辊,三组移钢传动机构用同步轴相连,连锁控制的方式,对棒材冷床进行改造.改造后棒材定尺率、成材率明显提高,经济效益显著.     

Scale Tests of Smoke Filling in Large Atria

The large Atriums of airports and railway stations facilitate the access to transport vehicles including shopping malls, cultural spaces, etc. For this reason, they are used by an elevated number of passengers and visitors. Numerous malls contain a large atrium too, as a principal access or as a food court, and they usually have high occupant loads. In case of fire, the smoke can affect human health seriously, and people may be unable to reach a safe place before being overcome by the conditions created by the fire. The traditional approach to fire protection by compartmentation is not applicable to these large volume spaces and the ability of sprinklers to suppress fire in spaces with high ceilings is limited. This work evaluated—using scale tests, fire computer modeling and analytical methods—a comparative analysis of the different results obtained for the smoke control in large atria when the smoke filling approach is applied. Smoke layer and plume temperatures have been registered during the scale test—based on the Froude Modeling—and they have been compared opposite to the FDS scale simulation and the FDS large scale simulation. Smoke layer descend has been studied and compared for the scale test, the computer simulations developed and the empirical equations used. The results demonstrated that the evacuation time calculation is conservative when the zone computer model CFAST, the field computer model FDS or the empirical equations are used, although it turns out to be difficult to define the interface height based on the temperatures registered during the scale tests. The zone computer models generate results faster than field computer models or smoke tests, so it would be necessary to develop better calculation algorithms to define the smoke layer interface.

地下储气井在天然气加气站的应用

地下储气井储气建造成本低,占地面积小,安全性能高,现已成为国内CNG加气站首选储气方式。介绍了高压地下储气井的特点及技术指标、关键技术、运行事故与对策、安全技术措施。     

LPG储灌厂改为天然气储配站的探讨

结合石家庄市LPG储灌厂改为天然气门站及储配站的工程,从原LPG储灌厂的地理位置、改造后现有设施的可利用性、改造后是否影响城市LPG供应、球罐改造利用的可行性及可操作性等方面论述了LPG储灌厂改造为天然气门站及储配站的可行性,阐述了改造方案.     

压缩天然气供应若干问题的分析

分析了压缩天然气钢瓶拖车的充装压力、牵引车头与钢瓶拖车数量的确定，讨论了汽车加气站流程。     

解决变形缝问题的施工技术

分析了房屋裂缝的危害性以及设置变形缝的优缺点，筒述了后浇带代替变形缝的施工技术，并探讨了理论依据，提出了后浇带的设置要求，以确保工程质量。     

水泥粉煤灰混合料在台背回填中的应用

介绍了水泥粉煤灰混合料的强度和形成机理,从施工前准备、工艺流程等方面,阐述了水泥粉煤灰混合料在台背回填上的施工工艺,经工程应用效果可知,水泥粉煤灰混合料既节约资源又保护环境.     

正交法分析超细砂煤矿充填料配合比

用正交试验法分析研究了水泥、粉煤灰、三种外加剂及充填料质量浓度对充填料各性能指标的影响。结果表明:提高充填料的质量浓度,可以缩短其凝结时间,但其流动度会降低;提高水泥掺量可以提高充填料的强度。充填料最优配合比为普通硅酸盐水泥440kg/m~3、粉煤灰400kg/m~3、减水剂11kg/m~3、激发剂11kg/m~3、促凝剂110 kg/m~3,充填料最优质量浓度为80%。     

四川省及重庆市CNG汽车与加气站发展回顾

论述了四川省及重庆市发展压缩天然气汽车与加气站20年来的过程、成就、经验与有待改进之处,可为其他城市发展压缩天然气汽车项目提供参考。     

抗滑表层沥青混合料试验参数研究

针对近年来沥青路面抗滑表层混合料在生产中暴露出来的耐久性差、抗滑能力不持久等问题 ,认为不能简单的对这一级配形式予以否定 ,并尝试通过对其击实次数、空隙率指标等关键试验参数进行调整以改善其路用性能。在理论分析与试验研究的基础上 ,提出在抗滑表层混合料配合比设计中 ,将规范要求的马歇尔试件双面 5 0次击实改为 75次 ,同时相应降低空隙率要求 ,对保持路面抗滑性能与耐久性能之间的平衡、提高混合料的各项路用性能具有重要的意义