紫坪铺水库对附近断层稳定性影响的探讨

汶川地震的发生与其附近的紫坪铺水库是否有关是一个引起国际关注的问题.考虑水库的实际形状和蓄水深度,使用半无限空间的解析解,分析讨论了水库蓄水和放水过程对周围区域断层稳定性的影响.结果表明,对于倾角较小的断层面,水库放水使库区下方近地表的库仑应力有明显增加,增量达到0.2MPa,远离水库区域的库仑应力呈现象限性特征,而且随着距离的增加迅速减小.汶川地震震源落在蓄水时库仑应力减小、放水时库仑应力增加的区域内,但由于距离水库较远的原因,汶川地震前放水时库仑应力的增量只有0.005MPa左右.     

FDX-1A型粉尘静电消除监测仪的研制

本文介绍了FDX-1A型粉尘静电消除监测仪的设计思想与基本原理、样机性能测试报告以及现场使用结果。该监测仪既能监测静电,又能消除静电,而且消电能力很强,达到了一机两用的设计目的。     

Simplified analysis for reflective overpressure on walls of rectangle-section tunnel due to its inner-explosion

Based on the constructing thought of the displacement model of isoparametric finite element, an extended interpolating algorithm is deduced for calculating the overpressure history of an optional point on the walls of the rectangle-section tunnel under an optional point-explosion in its internal space. According to the working principle, the overpressure histories of all nodes on the walls of a tunnel with the equal width and height of 2 m, induced by a reference-charge explosion at each node in this tunnel's cross section, are computed using the LS-DYNA software, and then are gathered to establish a reference database, which makes it possible to set optionally the positions of the explosive and the overpressure-observed point. In addition, some variation factors of peak values and durations of overpressure on the walls, reflecting some changes on the charge weight and the sizes of width and height of the section, are included in this algorithm in order to simulate approximately the overpressure responses on the walls under the optional charge weight and cross-section size. Some example analyses indicate the rapidity and validity of this method, and therefore this will bring it a good prospect in engineering application.     

Constitutive Laws of the Underground Opening Collapse due to Dynamic Load

The constitutive laws of the collapse of underground openings in a rock massif were investigated based on the results of laboratory and field experiments,and computations using analytical and numerical models.It is shown that the principal mechanism of failure of underground openings over important for practice peak particle velocity amplitude range of 1 to 10 m/s is the roof and wall breakage due to the fall of key blocks.Over this load range the material crushing is of considerably less importance.The geometry of discontinuities influences mainly the stability of key blocks.Further caving depends weakly on block structure of near-tunnel zone.The mean volume of fall material is a rather stable quantity for rock massifs of different structures.Lower tunnel stability in the zones of high fracturing is caused by a higher probability of the presence of the unstable key blocks and the decrease of strength characteristics of fractured bounding blocks.The decrease of average block size is a less important accompanying factor.     

Effect of Shock Wave on Fabricated Anti-Blast Wall and Distribution Law Around the Wall Under Near Surface Explosion

The loads of shock wave effect on fabricated anti-blast wall and distribution law around the wall were investigated by using near surface explosion test method and FEM. The pressure-time histories and variety law on the foreside and backside of the anti-blast wall were adopted in the tests of variety of different explosion distances and dynamites, as well as in the comparison between the test and numeri-cal calculation. The test results show that the loads of shock wave effect on the anti-blast wall were es-sen-tially consistent with calculation results using criterion under surface explosion when explosion dis-tances exceed 2 m, the distribution of overpressure behind wall was gained according to variety law based on small-large-small. It is also demonstrated that the peak overpressure behind wall had com-monly appeared in wall height by 1.5—2.5 multiples, and the peak overpressures of protective building behind wall could be reduced effectively by using the fabricated anti-blast wall.     

量纲分析及其在原子物理中的应用

文章对量纲分析原理做了梳理归纳,并对于原子物理中的一系列关系式进行了量纲分析,包括氢原子的特征量、黑体辐射公式中的物理量、α粒子库仑散射特征量、与磁场有关的物理量.     

Response of Box-Type Structures Under Internal-Blast Loading

The tests of box-type structures under internal-blast loading are carried out. Then a numerical analysis of the test structures is done using a fully coupled numerical finite element model. The break-up process of the structure is simulated. The failure modes of the simulated structure agree well with the experimental results. The effects of the size of the reinforcing bars and the detailing of connections among the rebars in the concrete on the throw velocity of the fragments are discussed.     

中国专利激增动因及创新力研究

“专利激增”现象解读可起到较好的自我审视与警醒作用.在回顾了1980年代欧、美、日、韩及中国台湾地区专利激增理论及实证研究的基础上,梳理解读基于专利计量的中国专利激增动因及创新力研究.经过数年努力中国“傲人”的专利申请“量变”尚未产生令人信服的创新能力“质变”.近年的创新政策“组合拳”所产生的协同效应,仅在沿海开发区的一批新兴ICT企业的国际化发展道路上得到了一定程度体现.中国是时候驻足反思,努力寻求一条适合自身创新能力建立的路径.一方面,专利与创新制度建设应在“质”与“量”的选择间溯本求源;另一方面,企业应紧跟全球产业市场脉搏,不断夯实自身研发基础,力争成为全球创新与专利战备竞赛场上一员.