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本文系统地阐述了我军最新研制的野战X射线诊断车屏蔽车厢的研究。该车厢的设计充分考虑了野战使用特点,采用在铝塑复合大板基础上黏附一定厚度的铅板构成铅铝复合大板。对该大板制作的屏蔽车厢辐射水平的检测表明,在每昼夜200名伤员的作业能力下,该车厢控制间内和车厢周围的分时剂量和年总剂量辐射水平都达到标准要求,保证了医务人员和公众的健康。 相似文献
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针对许多桥梁的防撞墩承台部分位于水下且围堰施工成本较大的问题,借助某防撞墩施工实际,对防撞墩承台下沉式施工技术及其应用进行了探讨,可为同类工程提供参考. 相似文献
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王海涛 《交通世界(建养机械)》2013,(23):171-172
前言
泡沫混凝土具有轻质高强、节能利废、保温隔热、隔声以及冲击能量吸收性能好等优良特性,可用于高等级公路、地铁等基础设施建设,降低高填方段、地铁隧道、地下连续通道等的回填荷载。从而有效解决软基路堤的桥头跳车、道路拓宽以及高寒地区路堤隔热保温等问题,增大道路工程的稳定与安全系数。 相似文献
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针对传统采集系统价格昂贵、接口不灵活、实时性差等缺点,提出一种基于LabWindows/CVI的高速数据采集系统.该系统使用Universal Serial BUS 2.0(USB2.0)接口,以LabWindows/CVI搭建数据采集系统的软件平台,采用调用动态链接库的方法完成上位机和系统间的通信,利用LabWindows/CVI的多线程实现数据的实时采集.试验结果表明:该系统调试方便、界面友好、实时性好、运行稳定,可广泛使用. 相似文献
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The damage critical curved surface is derived by considering the related effect of isotropic damage and degradation of cohesion and internal friction angle of Mohr-Coulomb strength law. The characteristics of stress-displacement curve and networks of shear bands with the change of degree of damage, confining pressure and Poisson??s ratio are investigated numerically by monitoring the stress-displacement values in the process of deformation of samples under plane strain and different initial conditions. The dependence of elastic-plastic response of localization is discussed. The non-uniqueness of the solution of equation is given. The orientation angle of shear band is derived by considering the related effect of isotropic damage and degradation of cohesion and internal friction angle. The orientation angle of shear band obtained by numerical simulation is contrasted to the orientation angle by measuring Mohr circle. It is shown that peak strength and residual strength depend on confining pressure. The networks of shear bands begin to appear in phase II of elasticity and develop in soften phase, and the shear band is formed in the phase of residual strength. As the degree of damage increases, axial displacement at the points of bifurcation and shear band decreases. The orientation angle of shear band increases with the increase of the damage degree. The orientation angle of shear band obtained by numerical simulation and measuring Mohr circle is not much difference when the damage degree is equivalent. The Mohr-Coulomb theory may predict the localized instability of sample by considering the degradation of cohesion and internal friction angle. 相似文献