Limiting drainage criterion for groundwater of mountain tunnel

Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance the tunnel construction and groundwater.To assess the related problems, an limiting drainage standard ranging from 0.5 to 2.0 m3/（m·d） was suggested for mountain tunnels based on survey and comparative analysis. After that, for the purpose of verifying the rationality of the standard, a calculated formula for dewatering funnel volume caused by drainage was deduced on the basis of the groundwater dynamics and experience method.Furthermore, the equation about the relationship between water discharge and drawdown of groundwater table was presented. The permeability coefficient, specific yield and groundwater table value were introduced, and then combined with the above equation, the drawdown of groundwater table under the proposed limiting drainage criterion was calculated. It is shown that the proposed drainage standard can reach the purpose of protecting ecological environment under the following two conditions. One is the permeability coefficient ranges from 10-4 to 10-5 m/s and the specific yield ranges from 0.1 to 0.001. The other is the permeability coefficient varies from 10-6 to 10-8 m/s and the specific yield varies from 0.1 to 0.01. In addition, a majority of common geotechnical layers are involved in the above ranges. Thus, the proposed limiting drainage standard which ranges from 0.5 to 2.0 m3/（m·d） for mountain tunnel is reasonable.     

金沙遗址博物馆文物英译名探究

通过对金沙遗址博物馆文物英译名的分析,探讨了文物名称翻译的标准和方法,以期为规范文物名称翻译和推动中华文化的对外交流及传播工作提供借鉴。     

Prediction of forming limit in hydro-mechanical deep drawing of steel sheets using ductile fracture criterion

It has been observed that the forming limit curve at fracture (FLCF) of steel sheets, with a relatively higher ductility limit have linear shapes, similar to those of a bulk forming process. In contrast, the FLCF of sheets with a relatively lower ductility limit have rather complex shapes approaching the forming limit curve at neck (FLCN) towards the equi-biaxial strain paths. In this study, the FLCFs of steel sheets were measured and compared with the fracture strains predicted from specific ductile fracture criteria, including a criterion suggested by the authors, which can accurately describe FLCFs with both linear and complex shapes. To predict the forming limit for hydro-mechanical deep drawing of steel sheets, the ductile fracture criteria were integrated into a finite element simulation. The simulation, results based on the criterion suggested by authors accurately predicted the experimetal, fracture limits of steel sheets for the hydro-mechanical deep drawing process.     

铝液充型过程水模拟技术的研究

以相似理论为理论基础，采用计算机可视化技术，分别进行了铝液、水、0．215％聚丙烯酰胺水溶液的充型可视化试验，拍摄、记录了试验过程。试验结果表明：以水作为模拟介质，从宏观上反映铝液的流动状态是可行的；但在水模拟流场的计算中，要想用水模拟流场客观真实的反映铝液的流场，使其具有更好的相似性，要适当地调整水的黏度，会使计算结果更可靠。     

双回转送进二辊冷轧管机凸轮设计研究

本文提出了双回转送进二辊冷轧管机凸轮理论轮廓曲线的新设计方法 ,其轮廓曲线加速度与跃度呈梯形 ,且跃度边界连续 ,给出了针对双回转送进二辊冷轧管机的两个过渡段具有等加速度和跃度的设计准则     

MODEL OF CLEAVAGE CRACK PROPAGATION ACROSS BOUNDARY

In the light of analysis of the features of cleavage fractographs of low carbon steel,the stresscriterion for cleavage crack propagation across ferrite grain boundary was established on thesupposition that resistance to the propagation results from an arbitrary mutual orientation ofthe cleavage plans in the neighbouring grains.On the basis of concept of statistical distribu-tion of cleavage plane in space,the probabilistic characteristic of cleavage process was ex-pounded,and the fracture stress of the cracked specimen over temperature range in whichfracture is initiated by cleavage mechanism was calculated by means of finite element analysisprogram and the calculated result was found to be in agreement with that measured.     

Lode应力参数与应力参量之间的内在联系及屈服准则的推广

从塑性力学应力Ｌｏｄｅ参数着手，深入研究了应力Ｌｏｄｅ参数与各应力参量之间的内在联系，并对塑性理论中屈服准则进行了合理推广。对塑性理论及其应用具有重要意义。     

解理裂缝过界扩展模型

根据对低碳钢解理断裂显微特征分析的结果,以相邻解理系统失配作为裂纹过界扩展的阻力源,建立了解理裂纹过界扩展的临界条件,并根据解理系统的空间分布的统计特性,对裂缝试样的解理断裂行为进行了计算模拟。计算结果与实验结果一致。     

晋东北金矿床石英流体包裹体与找矿

晋东北各种类型金矿中都广泛发育热液型石英脉，与矿化有关的石英流体包裹体的特征反映了不同的矿床类型。对该区石英脉型、蚀变岩型及磁铁石英岩型金矿床的研究表明，石英中流体包裹体的成分、温度和红外吸收光谱等特征可以作为划分矿床类型和作为金矿找矿评价的标志     

我国钢筋质量与国际先进水平的差距

回顾了我国近50年来带肋钢筋的生产状况，综述了国际上一些发达国家对普通钢筋不断提升质量水平的发展趋势及对钢筋标准的修订；并就我国在生产普通钢筋和修订标准、规范中应关注的若干问题提出了建议。