根据长期单向压缩试验结果确定三维流变模型参数

将一维西原模型的应力–应变关系推广为三维应力状态的弹-粘弹-粘塑本构方程,以其竖向应变表达式作为基本方程,对长期单向压缩试验结果进行曲线拟合,从而确定该流变模型的本构参数。该方法简便快捷,所获参数物理意义明确,可推广应用于其它流变模型的参数确定。     

交流伺服电机驱动--成形装备发展的新方向

用交流伺服电机代替普通交流异步电动机,使机械驱动的成形装备具有柔性化、智能化的特点,工作性能和工艺适应性大大提高,被称为第3代新型成形装备.介绍该技术的基本原理、典型产品和发展概况,讨论了目前发展中的若干关键问题.指出重载大扭矩交流伺服电机及其控制技术以及重载精密高效螺旋传动的开发是这一技术发展的关键;分析了各种传动方式的特点;探讨了伺服驱动节能的和利用"电子飞轮"储能解决大电流对电网冲击等问题.     

Influences of rainfall infiltration on stability of accumulation slope by in-situ monitoring test

In order to improve the understanding of the fundamental mechanism of rainfall infiltration induced landslides in accumulation slope and to clarify some important characteristics of slope performance, artificial rainfall simulation tests and field synthetic monitoring were carried out on a typical accumulation slope of Shangrui Freeway in Guizhou Province, China. The monitoring results show that the most accumulation landslides caused by rainfall infiltration are shallow relaxation failure, whose deformation zone lies within the top 0–4 m soil layer. The deformation of slope gradually reduces from the surface, where the greatest deformation lies in, to the deep part of slope. The average percentage of infiltration during the first 2 h is 86%, and then it reduces gradually with time because of the increase of the surface runoff. The average percentage of infiltration drop to a relatively stable value (50%) after 6 h. Rainfall infiltration causes obvious increase of pore-water pressure, which may result in a reduction of shear strength due to a decrease in effective stress and wetting-induced softening. The double-effect of rainfall infiltration is the main reason of rainfall infiltration induced landslides in accumulation slope. Foundation item: Project(50678175) supported by the National Natural Science Foundation of China     

荆州城区居民生活饮用水质量调查及分析

目的了解荆州市学校及城区居民生活饮用水卫生状况,防止水源性传染病的爆发流行提供科学依据。方法对长江宝塔湾、自来水厂、荆州市区内学校和家庭等多处水源进行抽样调查和水质监测,并对其结果进行分析。结果长江宝塔湾水源水10项指标均符合GB/T3838-2002《地表水环境质量标准》中Ⅲ类标准。经自来水公司处理后出厂水基本符合GB/T 5749-2006《生活饮用水卫生标准》,但浑浊度和COD分别达到1.4 NTU和4.1 mg/L,达到受水源和净水条件限制时要求。5个校区、3个家庭不同时段的龙头水检测指标基本符合国家标准,2所校区卫生间水源的菌落总数分别达到90 CFU/m L和98 CFU/m L,已经接近国标规定的100 CFU/m L。本次检测6个水样的氨氮其中4个不合格,不合格率为67%。结论荆州城区居民生活饮用水存在安全隐患,尤其是氨氮含量,建议有关部门加强管理,提高质量。     

TB水电站库区移民安置交通复建规划设计

根据库周交通现状和移民安置分布情况,采用总体路网规划构思,并充分考虑与区域路网结合,在“三原”原则基础上,采用交通量预测分析合理确定规模标准,进而使得规划方案更加完善,经济投入达到最佳效果,避免后期重复建设。