石灰石钠长阳起片岩配料生产高强水泥的实践

实践证明：用石灰石、钠长阳起片岩配料在五级旋风预热器窑中级烧水泥熟料，只要选择适宜的率值及窑的转速，就可以生产出高强水泥熟料，而且有利于改善生料的易烧性，提高入窑生料的CaCO3分解率，提高窑的产量。     

Stress variation of soil surrounding tunnel and grouting reinforcement effect based on stress release

With FLAC, a criteria of stress release ratio （SRR）, i.e., about 10% of the relative difference of the ground settlement before and after the supporting system is installed, is incorporated into stress release method （SRM）. At the same time, the Mohr-Coulomb Criterion is used to analyze stress changes around the tunnel induced by excavation. It shows that the surrounding soil around shallow tunnels can be partitioned by loosened zones （unloading zones） and plastic zones among which the shear stresses in the soil are less than 10 kPa below the M-C yield line. Both types of zones are separated. With the increasing of the SRR, the areas of plastic zones and loosen zones gradually increase. The surrounding soil is equally divided into 24 regions in order to study the influence of different grouting regions on the ground settlement. The reinforcing effect of grouting can be modeled by enhancement of the soil strength around the tunnel. By the approach of the SRM, numerical analysis indicates that, in the upper area （top of the surrounding soil about 210°）, the reinforcing effect gradually decreases as the reinforcing region moves from arch springing to the vault of the crown; when reinforcing regions lie in the upside of the surrounding soil, the influence on the ground settlement is generally greater than in the lower part; at the same time, with the increase of the SRR, the influential differences are more and more obvious.     

交流电动机绕组故障产生的原因、检查方法及处理方法

0 引言 工厂企业电动机是常用的拖动设备,它的故障严重影响着生产和经济效益.而绕组是电动机重要的组成部分,绕组的老化、受潮、受热、腐蚀性气体及灰尘侵蚀、异物侵入、机械力和电磁力的冲击等,长期过载、欠电压、过电压、缺相运行都能引起故障.     

国家新闻出版署表彰筹建印刷博物馆有贡献单位和人员

<正> 在中国印刷博物馆历时四年半的筹建过程中,筹委会办事机构及上海、香港、台湾三个办事机构的工作人员,海内外有关单位和人士,为集资、造馆、征物、布展、后勤、保安等做了大量组织协调和具体落实工作,作出了力所能及的贡献。