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121.
通过严密设计计算,精心施工,采用锚杆(预应力索)框架+面板+坡体排水工程等支护形式处理以永久性边坡,是目前较常用且有效的支护方法。本文详细介绍了锚杆(预应力索)框架+面板+坡体排水工程施工技术。 相似文献
122.
该文指出了断层构造带下支护方式存在的问题,阐述了在断层构造带附近围岩独特的变形特征。提出了新的支护方案,确保了巷道的长期稳定。 相似文献
123.
《Soils and Foundations》2014,54(4):621-638
The collapse of a filling occurred due to heavy rain in Higashi-Hiroshima City׳s Shiwa District at about 5:30 am July 25th, 2009. The filling was made of surplus soils, and it contained a mass of water supplied from rainfall and ground water flow of a permeable layer at the bottom of the filling. The collapsed soil flowed down and destroyed a house. In this paper, the cause of this disaster is discussed. The site of the disaster was used as the dumping site of surplus soils, after several changes of ground formation. The history of the geographical change was reconstructed by the image processing of old map, aerial photographs, result of 3-dimentional laser survey carried out after collapse and the measurement of thickness of collapsed soil by dynamic cone penetration test. According to the result of processing, the shape and the size of the filling before collapse was reconstructed. The relationship between the rainfall and the groundwater in the river sediments layer over which the filling was constructed was determined. A stability analysis of the filling was conducted considering the rise of the groundwater level in the filling and the laboratory measured strength parameters. The results of the stability analysis showed that the collapse would have taken place when the groundwater level rose by about 9 m due to the supply of groundwater through the river sediments layer. 相似文献
124.
《Geotextiles and Geomembranes》2014,42(6):576-585
The design of reinforced earth structures uses idealized two-dimensional (2D) geometry – classifying as a plane-strain analysis. This 2D idealization greatly simplifies design by ignoring stabilizing effects posed by three-dimensional (3D) characteristics. While the outcome of this 2D idealization is conservative in terms of required reinforcement strength, ignoring 3D end effects in back-calculations of experimental and field data may overestimate the contribution of the reinforcement to stability thus possibly leading to unconservative learned lessons related to design. The objective of this study is to explore 3D effects on the required strength of reinforcement in geosynthetic-reinforced earth structures (GRESs) using a modified 3D limit equilibrium (LE) slope stability analysis. To determine the stability of GRESs, a rotational, 3D failure mechanism, derived from variational LE analysis, is applied using a log-spiral surface generalized to 3D conditions. In order to determine the long-term strength of geosynthetics required to ensure sufficient internal stability, the moment equilibrium approach is applied and its respective equations solved. In order to conveniently assess the end effects on the required total strength of reinforcement and the volume of failing mass considering the feasible length of potential failure, a series of design charts are presented. These charts can also be useful in forensic studies when back-calculating the in-situ mobilized strength of the geosynthetic for 3D failures. The impact of seismicity and the assumed function of forces distributed amongst the reinforcement layers were investigated to highlight their importance. To keep this study focused on 3D end effects, this study is limited to a simple 3D GRES problem; however, extending the present framework to deal with complex homogenous problems is straightforward. 相似文献
125.
仓储企业分区拣货作业优化策略 总被引:1,自引:1,他引:0
随着商品流通量急剧增加,订单趋于小型化及商品的多元化,仓储企业常通过订单拣货作业将客户订单所需要的货品收集起来.通过分析拣货作业现状,提出高校而精确的拣货策略,指出动态分区拣货作业中协同调度思想,并用实际事例递进演示了协同调度机理,并证明了其有效性. 相似文献
126.
127.
Optical glass scratching can induce various types of cracks, among which median cracks are extremely detrimental and penetrate deeply under the surface. Due to deep-scratching process complexity, it is challenging to devise a method to predict median crack depth. Indentation testing has been examined comprehensively in prior research works. It has been found that using the correlation between scratch and indentation testing can simplify predictive method development. In this research, a numerical method based on indentation testing is proposed to determine median crack depth during deep scratching. In the first step, an FE model is configured to simulate the indentation testing process and the Cohesive Zone Method is applied to describe median crack behavior. The cohesive parameters calibrated through experimental indentation testing are implemented in the FE scratch model, and the results are compared with the experimental scratch test results. According to the results, the FE scratch model was enhanced by mode II fracture energy and the modeled friction coefficient. The indentation and scratch experiments were conducted with BK7, F2, Fused silica, K5, Pyrex, Quartz, SF6, and SF19. The experimental results prove that the nonlinearity of the median crack depth curve correlates with KIc. A comparison of the experimental and numerical results demonstrates the model is virtually functional for materials with KIc below 1000?kPa?m1/2. Comparisons between the current findings and other studies infer the model and experimental results are accurate and reliable. 相似文献
128.
129.
分析了层状岩体边坡的地质情况,通过有限差分数值建模,建立了边坡长短锚杆复合支护的优化方案,锚杆相间布置,长度分别为16m,12m,倾角为20°,通过计算,边坡加固后处于稳定状态。实践表明:长短锚杆复合支护是边坡加固的有效措施。 相似文献
130.
为了解决在白车身焊装中机器人与机器人,机器人与其他设备之间存在的干涉问题,本文利用干涉区的创建和设置,结合KUKA机器人语言[1]和现场总线控制技术的应用,有效地实现上述目的。在保障了安全性和可靠性的同时,也优化了生产节拍。 相似文献