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871.
强夯法在兴城临海产业区中的应用   总被引:1,自引:0,他引:1  
兴城临海产业区基础设施工程中,填方厚度在3~6m,回填土材料为山皮土,为了减少路基沉降,对道路路基范围内进行强夯处理,并进行相应的检测,满足路基设计要求,强夯处理软弱路基优点是经济、便捷、安全。  相似文献   
872.
为保证隧道塌方时施工人员有足够的逃生空间,结合具体工程,介绍了隧道逃生管设计要点,并对其在冲击荷载作用下的动力响应进行了弹塑性数值模拟。研究表明,逃生管变形随着落石尺寸的增大而增大,随着逃生管壁厚的增大而减小,随着与逃生管端部距离的增大而减小。  相似文献   
873.
针对实桥模型进行有限元模拟,运用反应谱法在模型中输入动力特性值运行分析,得出桥梁基本自振频率为6.214Hz,基本周期为1.011s,以及结构的部分自振频率及振型,并在水平和竖向地震作用下,进行了桥梁墩身部分的抗震计算,为桥梁在抗震安全性方面的分析提供参考依据。  相似文献   
874.
In the last decade, vehicle identification systems have become a central element in many applications involving traffic law enforcement and security enhancement, such as locating stolen cars, automatic toll management, and access control to secure areas. As a method of vehicle identification, license plate recognition (LPR) systems play an important role and a number of such techniques have been proposed. In this paper, we describe a method for segmenting the main numeric characters on a license plate by introducing dynamic programming (DP) that optimizes the functionality describing the distribution of the intervals between characters, the alignment of the characters, and the threshold difference used to extract the character blobs. The proposed method functions very rapidly by applying the bottom-up approach of the DP algorithm and also robustly by minimizing the use of environment-dependent image features such as color and edges.  相似文献   
875.
As the number of disabled people grows, independence and mobility become a priority for those individuals. To achieve this goal, a ‘Turny-type power seat’ was developed in this study to assist a disabled person rise from a vehicle without trouble. The design and modeling of the power seat were performed using AutoCAD and CATIA software. The major motions of the power seat system are swiveling, sliding, and extending, which are accomplished primarily by DC motors, chains, and gears. Most of the power seat parts were made from mild steel. Welding technology was used throughout the frame fabrication. To ensure the safety and stability of the power seat, various tests were performed, and the results analyzed. The static analysis of the power seat was carried out by ANSYS 11.0. The results showed that the power seat conformed to the Americans with Disabilities Act (ADA) standards. The durability test was performed by repeatedly rotating and sliding the power seat under loading conditions. Dynamic crash simulation was carried out using the LS-DYNA software. The durability test ensured a longer life of the power seat, while the crash analysis showed a small rotational distortion that was not harmful to passengers. However, the front seat had a slightly larger forward displacement, which was not comfortable for passengers. Therefore, further modifications of the power seat should be done to improve the performance, with attention given to the reduction of the forward displacement in the event of a crash.  相似文献   
876.
灰色关联法分析沥青混合料高温稳定性影响因素   总被引:1,自引:0,他引:1  
采用灰色系统关联度分析法从数学的角度研究了沥青混合料各组成因素与动稳定度之间的关系.分析结果表明,粗集料的含量对沥青混合料的动稳定度影响较大,其次为沥青含量,这对沥青混合料研究以及设计有一定的指导意义.  相似文献   
877.
采用流体力学中的束流理论,分析了液流在液力缓速器中的动力学和运动学状态,推导出液力缓速器制动力计算公式和充放液时间计算公式.在数学计算软件MATLAB的仿真丁具箱SIMULINK中建立液力缓速器制动力动态仿真模型,以某45 t重型车辆参数作为仿真数据,考虑液力缓速器充液时间,得到了一组重型车辆在不同工况下缓速器制动仿真结果.分析仿真结果并得出了相关结论.  相似文献   
878.
To investigate the seismic performance of the double-row pre-stressed anchor piles (DRPAPs) on the Yuxi-Mengzi railway, FLAC3D was used to construct a three-dimensional model. Using Koyna earthquake records as input motions, dynamic time-history analyses were carried out. In the analyses, we compared earth pressure on the front and back of the piles and deformation of the piles under different seismic forces with or without anchor cables. With the anchor cable present, the earth pressure on the back of the pile s free section increases, but that on the back of the pile s anchorage section decreases. Also, with anchor cables, the earth pressure on the front of the upper pile decreases, and that on the back of the lower pile decreases.  相似文献   
879.
A vehicle-track-bridge coupling dynamics model was built based on the theory of vehicle-track coupling dynamics. Using this model, a comparison was made between the dynamic response of an elastic sleeper ballasted track and a common sleeper ballasted track on bridge under the same working conditions. The results show that laying elastic sleepers on the bridge could solve the problem of large track stiffness caused by a thin ballast thickness, and improve the dynamic response of the bridge. This is beneficial to train operation safety and riding comfort.  相似文献   
880.
岩溶地带公路隧道地震动力响应研究   总被引:1,自引:0,他引:1  
基于土—结构相互作用模型,利用粘—弹性边界条件,运用时程分析方法研究了岩溶地带公路隧道地震动力响应。探讨了溶洞发育程度和位置对隧道地震动力响应的影响,总结了岩溶地区公路隧道结构位移场、围岩塑性区等的地震动力响应分布规律。  相似文献   
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