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上海中心城区尤其是苏州河沿岸多为合流制排水泵站,汛期初期雨水放江情况下的短时水质状况仍然不容乐观,缺乏有效的监测与控制。为此,阐述了拟在苏州河沿岸排水泵站开展水质水量监测系统的研究工作,主要包括监测系统的总体设计方案、建设内容及系统的功能等。该系统的建成将实现对苏州河沿岸排水泵站放江水质水量的实时监控,为后续工程性措施及优化泵站运行提供依据,为上海建设"智能苏州河"提供基础数据与技术支撑。 相似文献
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上海北横通道工程由于工程总体线位及周边环境条件制约,需要在长寿路苏州河桥南侧采用地下隧道形式穿越苏州河。苏州河作为上海市非常重要的防汛排水通道,还具有一定的航道功能,如何保证在满足苏州河防汛安全的前提下实施地下通道是工程可行的前提。受到穿越节点总体布置、周边环境的制约,采用明挖法穿越苏州时成为唯一可选用的工艺,从而使北横通道成为上海首次采用明挖法穿越苏州河的工程。在明挖方案深化过程中,围堰方案的确定、防汛影响、航道影响是方案研究过程中必须要研究解决的问题,通过一系列的研究,最终确定了北横通道明挖穿越苏州河的总体方案。 相似文献
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为了建设符合中国国情的地下排水深隧,解决城市内涝问题,消除"城市看海"现象,采用调研分析的研究方法,通过调研国外城市排水深隧建设的成功案例,借鉴成熟经验并结合我国国情探索出我国城市排水深隧在规划设计、施工技术等方面的建设模式。主要结论如下:1)深隧规划必须坚持雨污分流原则,防涝标准应设为百年一遇;2)深隧层位应建于地下30~50 m的位置,隧道管线应布设在城市易涝区,并且将修建深隧、改造浅管和清淤河道衔接起来,形成一套完整的防洪排涝系统,让深隧的作用得以充分发挥,才能解决城市内涝问题;3)排水深隧要注重防水设计,防止雨水污染地下水;4)为提高深隧的经济效益,应将深隧与地下快速路的规划结合起来,功能上多样化。 相似文献
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为进一步完善地区路网结构,均衡外环线和中环线的交通负荷,提升地区交通条件,真光路跨苏州河桥梁新建工程计划于2013年开工建设。工期498天。该工程南起长宁区剑河路金钟路交叉口,沿剑河路向北经过清池路,分别跨越北翟路、苏州河和规划光复西路后, 相似文献
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《隧道建设》2014,(6):538-538
<正>广州东濠涌深层隧道尚未正式动工,新的深层隧道建设又纳入规划。2008年,广州市政府与全市13个治水责任主体签订"责任状",启动了新一轮大规模"治水"。2016年底建成东濠涌深隧2020年建成猎德涌等深隧广州市委、市政府制定了《广州市生态水城建设规划(2014—2020年)》及《广州市生态水城建设实施方案(2014—2016年)》,明确了未来6年的治水任务。除了已经规划的东濠涌深层隧道试验段工程外,广州还将规划建设多条深层隧道工程。东濠涌深层隧道试验段工程于2012年开始规划,2013年通过环评。该试验段工程总长1.7 km,拟投资7.7亿元,原计划2013 相似文献
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以《淄博市中心城区及桓台县排水(雨水)防涝综合规划》为例,介绍海绵城市建设、低影响开发、大排水系统等规划理念在淄博市中心城区及桓台县的应用。规划在对现状排水系统改造、利用的基础之上,由传统单一措施向组合措施转变,进而实现提高排水防涝水平、转变排水理念、推行雨洪利用等多重目标。为类似规划编制提供了一定的思路基础,有着较强的借鉴意义。 相似文献
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根据1995年国务院批复的南京市过江通道"五桥一隧"规划,建设中的南京长江第四大桥北接线需在六合境内的主要防洪通道——滁河,建设滁河特大桥。该文首先对滁河流域和滁河特大桥处的水文地理与地质特性进行了介绍;依据《长江流域综合利用规划简要报告》和地方水利规划,结合流域防洪标准、水文特性,采用平面二维水流数学模型法,对滁河特大桥建成后其对流域与河道防洪能力的影响进行了分析计算;通过大桥建设后桥身的雍水和建设前后河道水流场的计算分析与对比,得出滁河特大桥建成后对流域与滁河河道防洪能力影响较小,且滁河特大桥工程设计满足防洪要求的结论。最后,对大桥建设过程中应当对河道及河堤采取的相应防护工程措施提出了建议。 相似文献
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This paper presents a fatigue design method for plug and ring type gas welded joints, which incorporates welding residual
stress effects. A non-linear finite element analysis (FEA) was first performed to simulate the gas welding process. The numerically
predicted residual stresses of the gas welds were then compared to experimental results measured using a hole drilling method.
In order to evaluate the fatigue strength of the plug and ring type gas welded joints, a stress amplitude (σ
a
)
R
taling the welding residual stress of the gas weld into account was introduced and is based on a modified Goodman equation
incorporating the effect of the residual stress. Using the stress amplitude (σ
a
)
R
, the ΔP-N
f
relations obtained from fatigue tests for plug and ring type gas welded joints having various dimensions and shapes were
systematically rearranged into (σ
a
)
R
-N
f
relations. It was found that the proposed stress amplitude (σ
a
)
R
could provide a systematic and reasonable fatigue design criterion for the plug and ring type gas welded joints. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(7):948-968
This paper presents an approach to design a delay-dependent non-fragile H∞/L2–L∞ static output feedback (SOF) controller for active suspension with input time-delay. The control problem of quarter-car active suspension with actuator time-delay is formulated to a H∞/L2–L∞ control problem. By employing a delay-dependent Lyapunov function, new existence conditions of delay-dependent non-fragile SOF H∞ controller and L2–L∞ controller are derived, respectively, in terms of the feasibility of bilinear matrix inequalities (BMIs). Then, a procedure based on linear matrix inequality optimisation and a hybrid algorithm of the particle swarm optimisation and differential evolution is used to solve an optimisation problem with BMI constraints. Design and simulation results of non-fragile H∞/L2–L∞ controller for active suspension show that the designed controller not only can achieve the optimal performance and stability of the closed-loop system in spite of the existence of the actuator time-delay, but also has significantly improved the non-fragility characteristics over controller perturbations. 相似文献
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Reservation-based intersection control for autonomous vehicles has the potential to make greater use of intersection capacity. Indeed, previous studies on the first-come-first-served (FCFS) policy (which prioritizes vehicles by order of their reservation request) have shown improvements over optimized signals. However, in certain situations, such as asymmetric intersections, FCFS easily performs worse than signals. To address this issue, we propose two new reservation policies, WEIGHTED and PHASED. WEIGHTED weights vehicle delay by signal timings, and PHASED simulates a signal but allows red phase turning movements that will not cause a collision. We test these policies on a city network and an arterial bottleneck intersection subnetwork and show that PHASED performs better than WEIGHTED in some scenarios, and vice versa. Furthermore, we show that using a combination of PHASED and WEIGHTED can perform better than using either one alone for the entire network. Results show that these policies provide effective and easily implemented alternatives to FCFS for reservations. 相似文献
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In this paper, a novel controller, the fractional order PDμ controller, is designed to improve the performance of the driver-vehicle system. First, fractional calculus and fractional
order PIλDμ controller are introduced. A control algorithm for vehicle directional control using the fractional order PDμ controller is then presented. Based on preview-follower theory, the on-line tuning method of the fractional order PDμ controller is designed. By comparing simulated and experimental results, the validity and robustness of the proposed fractional
order PDμ controller in the closed loop system are verified. Finally, comprehensive evaluations are performed between the systems with
the fractional order PDμ controller and with an integer PD controller. The results demonstrate that the use of the fractional order controller leads
to an improvement of the performance of the driver-vehicle system. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):789-814
Wheel–rail contact calculations are essential for simulating railway vehicle dynamic behavior. Currently, these simulations usually use the Hertz contact theory to calculate normal forces and Kalker's ‘FASTSIM’ program to evaluate tangential stresses. Since 1996, new methods called semi-Hertzian have appeared: 5 7 (STRIPES). These methods attempt to estimate the non-elliptical contact patches with a discrete extension of the Hertz theory. As a continuation of 2, a validation of the STRIPES method for normal problem computing on three test cases is proposed in this article. The test cases do not fulfill the hypothesis required for the Hertz theory. Then, the Kalker's FASTSIM algorithm is adapted to STRIPES patch calculus to perform tangential forces computation. This adaptation is assessed using Kalker's CONTACT algorithm. 相似文献
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J. Jung J. H. Lee S. Song K. M. Chun 《International Journal of Automotive Technology》2008,9(4):423-428
Understanding the mechanism of carbon oxidation is important for the successful modeling of diesel particulate filter regeneration.
Characteristics of soot oxidation were investigated with carbon black (Printex-U). A flow reactor system that could simulate
the condition of a diesel particulate filter and diesel exhaust gas was designed. Kinetic constants were derived and the reaction
mechanisms were proposed using the experimental results and a simple reaction scheme, which approximated the overall oxidation
process in TPO as well as CTO. From the experiments, the apparent activation energy for carbon oxidation with NO2-O2-H2O was determined to be 40±2 kJ/mol, with the first order of carbon in the range of 10∼90% oxidation and a temperature range
of 250∼500°C. This value was exceedingly lower than the activation energy of NO2-O2 oxidation, which was 60±3 kJ/mol. When NO2 exists with O2 and H2O, the reaction rate increases in proportion to NO2. It increases nonlinearly with O2 or H2O concentration when the other two oxidants are fixed. 相似文献
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A robust H
∞ preview control is investigated for an active suspension system with look-ahead sensors. The uncertain system is described
by a state-space model with linear nominal parts and additional nonlinear time-varying norm-bounded uncertainties. Proof of
robust stability and a feedback-type robust H
∞ preview controller are derived by augmenting the dynamics of the original system and previewed road input. As, however, the
augmented previewed road input gives the system a much larger dimension than the original system, much more computation time
is required for solving of Riccati equations. To resolve this problem, a decomposed robust H
∞ preview controller is proposed. Robust stability and performance variations for system uncertainties are shown using a numerical
example of a quarter-car model. 相似文献