scholarly journals Fuzzy Assessment of Steel Deck Pavement for Long Suspension Bridge of the Fourth Nanjing Yangtze River Bridge

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Jinyu Zong ◽  
Keqiang Zhang ◽  
Binggen Zhan ◽  
Rui Ma
Keyword(s):  
Yangtze River ◽  
Evaluation Method ◽  
Suspension Bridge ◽  
Impact Factors ◽  
Engineering Practice ◽  
Fuzzy Evaluation ◽  
Long Span ◽  
Fuzzy Assessment ◽  
Scheme Evaluation ◽  
Steel Deck

The Fourth Nanjing Yangtze River Bridge (the Fourth Bridge) with the main span of 1418 m is the largest three-span suspension bridge in China and the third largest in the world. The service circumstance of steel deck pavement on the Fourth Bridge is complex and severe, so that the scheme evaluation for steel deck pavement is a huge program. To rapidly and comprehensively evaluate the schemes for pavement, a fuzzy evaluation method was introduced in this paper. A three-level logical assessment structure including 21 basic impact factors was built according to analytic hierarchy process (AHP), and the weight for each judgment matrix was determined by the Delphi method. Consequently, a fuzzy evaluation theory was used to value each scheme to propose the optimal one. Based on this method, four pavement schemes were evaluated to choose the optimal one, and the performance of the optimal scheme was highly corresponding to the practical engineering practice. The fuzzy evaluation method can supply a theoretical support to fast determine the scheme for long-span steel deck pavement.

scholarly journals Research on Establishing City Low Carbon Economy Evaluation Theory Model

2014 ◽  
Vol 8 (1) ◽  
pp. 446-450
Author(s):  
Xiao Wei
Keyword(s):  
Yangtze River ◽  
Evaluation System ◽  
Evaluation Method ◽  
Fuzzy Ahp ◽  
Fuzzy Evaluation ◽  
Low Carbon ◽  
High Carbon ◽  
Low Carbon Economy ◽  
Carbon Economy ◽  
Economy Evaluation

To explore the method of creating a theoretical model of urban low-carbon economy evaluation, and analyze the development status and level of low carbon economy in cities in the middle and lower reaches of Yangtze River; Method To introduce the basic theory of low-carbon economy, the principle and the technical route for creating the evaluation system of urban low-carbon economy, develop 3 layers of 5 categories of 18 evaluation indicators, conduct weighted calculation using Delphi method, analytic hierarchy process(AHP) , fuzzy evaluation method and fuzzy AHP method, investigate into 7 cities, such as Shanghai, Nanjing in the middle and lower reaches of Yangtze River, and evaluate the urban low-carbon economic status using the created models; Results The evaluation result shows that at present China has many cities at “medium to high carbon economy” or “high carbon economy” types. The development level of low-carbon economy lagged behind many western countries; Conclusion It is a most efficient pathway to improve the present low-carbon economic level by vigorously developing the low-carbon technology, developing the low-carbon environmental education and promoting the low-carbon concept.

Optimization Algorithm of Resource Allocation Based on Fuzzy Assessment Method

2014 ◽  
Vol 556-562 ◽  
pp. 3896-3900
Author(s):  
Yao Lei Li ◽  
Cong Xian Wang ◽  
Zhen Jia Li
Keyword(s):  
Technology Education ◽  
Evaluation System ◽  
Evaluation Method ◽  
Assessment Method ◽  
Fuzzy Evaluation ◽  
Technology Evaluation ◽  
Educational Perspective ◽  
Set Up ◽  
Fuzzy Assessment ◽  
Technology Teaching

The technology teaching of university basketball general course is a focus which all sectors of the community should pay more attention. How will the technology teaching of university basketball general course carry out optimization of integration, to play the biggest role, is also the key point of this paper. This paper from the main content of post-modern education and university basketball general course technology teaching, to understand the current situation of university basketball education, and construct basketball general course technology evaluation system. At the same time, using fuzzy evaluation method to do statistical analysis on the situation of basketball general course technology education, and in a targeted manner to set up teaching mode of basketball general course technology under Post-modern educational perspective, use the society, network, universities' and other resources effectively, to sharing the resources, realize technology education and the optimization configuration of resource.

Seepage Analysis and Construction Practice of Anchorage Circular Foundation Excavation in Long-Span Suspension Bridge

2011 ◽  
Vol 90-93 ◽  
pp. 128-132 ◽  
Author(s):  
Xiao Ling ◽  
Rong Hui Wang
Keyword(s):  
Finite Difference Method ◽  
Suspension Bridge ◽  
Engineering Practice ◽  
Preliminary Design ◽  
Three Dimension ◽  
Curtain Wall ◽  
Seepage Analysis ◽  
Long Span ◽  
Excavation Process ◽  
Construction Practice

Abstract：On the basis of preliminary exploration, complement exploration is executed to obtain excavation seepage analysis detail parameters. According to the three-dimension finite difference method and regulating calculation method, the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south and the influence of different depth rock-socketed on foundation seepage are discussed. With the experience in similar projects at home and abroad, the depth of diaphragm wall embedded in weak weathered rock is not less than 3 meters, grouting curtain wall consists of 10 meters, and the waterproof curtain outside the foundation is canceled from preliminary design. The stress, strain and water level are monitored during the excavation process, and the deformation of the supporting structure is within the control. The structure is under reasonable force and the sealing effect is obvious when the foundation is excavated. Construction practice shows that the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south are consistent with engineering practice.

Probability Evaluation Method for Cable Safety of Long Span Suspension Bridges under Extreme Wind Load

2010 ◽  
Vol 163-167 ◽  
pp. 3223-3229 ◽  
Author(s):  
Jun Hu ◽  
Jin Ping Ou
Keyword(s):  
Safety Assessment ◽  
Evaluation Method ◽  
Suspension Bridge ◽  
Wind Load ◽  
Structural Safety ◽  
Suspension Bridges ◽  
Type I ◽  
Attenuation Relations ◽  
Long Span ◽  
Extreme Wind

The cable is the main load-bearing component of suspension bridge and its safety assessment under extreme wind load is a key issue to the structure. Take a long-span suspension bridge in the East Sea China as an example, the standard of extreme wind load for structural safety evaluation is established; the wire’s strength model is established by the type I extreme value distribution; cable’s safety assessment function under wind load is established and the Monte Carlo method is used to get the cable’s reliability and reliable indicators. The bridge’s re-service term is taken for 90 years as an example, the results indicate that the wire’s serial effects can’t be ignored, the cable’s reliable indicator decreases as the number of broken wires increases in approximately the linear attenuation relations, the critical percentage of broken wires is about 10%.

A fuzzy evaluation method of road vehicle automatic weighing instrument in dynamic force metrological performance

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1365-1372
Author(s):  
Xiaohui Mao ◽  
Liping Fei ◽  
Xianping Shang ◽  
Jie Chen ◽  
Zhihao Zhao
Keyword(s):  
Evaluation Method ◽  
Comprehensive Evaluation ◽  
Evaluation Model ◽  
Dynamic Performance ◽  
Dynamic Force ◽  
Fuzzy Evaluation ◽  
Road Vehicle ◽  
Evaluation Standard ◽  
The Road ◽  
Metrological Performance

The measurement performance of road vehicle automatic weighing instrument installed on highways is directly related to the safety of roads and bridges. The fuzzy number indicates that the uncertain quantization problem has obvious advantages. By analyzing the factors affecting the metrological performance of the road vehicle automatic weighing instrument, combined with the fuzzy mathematics theory, the weight evaluation model of the dynamic performance evaluation of the road vehicle automatic weighing instrument is proposed. The factors of measurement performance are summarized and calculated, and the comprehensive evaluation standard of the metering performance of the weighing equipment is obtained, so as to realize the quantifiable analysis and evaluation of the metering performance of the dynamic road vehicle automatic weighing instrument in use, and provide data reference for adopting a more scientific measurement supervision method.

Control of Vibrations due to Moving Loads on Suspension Bridges

2006 ◽  
Vol 11 (3) ◽  
pp. 293-318 ◽  
Author(s):  
M. Zribi ◽  
N. B. Almutairi ◽  
M. Abdel-Rohman
Keyword(s):  
Bridge Deck ◽  
Suspension Bridge ◽  
Lyapunov Theory ◽  
Dynamic Responses ◽  
Suspension Bridges ◽  
Control Force ◽  
Moving Loads ◽  
Hydraulic Actuator ◽  
Long Span ◽  
Suspended Cables

The flexibility and low damping of the long span suspended cables in suspension bridges makes them prone to vibrations due to wind and moving loads which affect the dynamic responses of the suspended cables and the bridge deck. This paper investigates the control of vibrations of a suspension bridge due to a vertical load moving on the bridge deck with a constant speed. A vertical cable between the bridge deck and the suspended cables is used to install a hydraulic actuator able to generate an active control force on the bridge deck. Two control schemes are proposed to generate the control force needed to reduce the vertical vibrations in the suspended cables and in the bridge deck. The proposed controllers, whose design is based on Lyapunov theory, guarantee the asymptotic stability of the system. The MATLAB software is used to simulate the performance of the controlled system. The simulation results indicate that the proposed controllers work well. In addition, the performance of the system with the proposed controllers is compared to the performance of the system controlled with a velocity feedback controller.

scholarly journals Current and New Approaches to Predict the Deflections of One-Way Flexural Members with a Focus on Composite Steel Deck Slabs Voided by Circular Tubes

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 421
Author(s):  
Chang-Hwan Lee ◽  
Iman Mansouri ◽  
Jaehoon Bae ◽  
Jaeho Ryu
Keyword(s):  
Structural Function ◽  
Flexural Members ◽  
Long Span ◽  
Deck Slabs ◽  
New Type ◽  
New Perspective ◽  
Flexural Tests ◽  
Prediction Approach ◽  
Steel Deck

A new type of composite voided slab, the TUBEDECK (TD), which utilizes the structural function of profiled steel decks, has recently been proposed. Previous studies have confirmed that the flexural strength of TD slabs can be calculated based on the full composite contribution of the steel deck, but for long-span flexural members, the deflection serviceability requirement is often dominant. Herein, we derived a novel deflection prediction approach using the results of flexural tests on slab specimens, focusing on TD slabs. First, deflection prediction based on modifications of the current code was proposed. Results revealed that TD slabs exhibited smaller long-term deflections and at least 10% longer maximum span lengths than solid slabs, indicating their greater efficiency. Second, a novel rational method was derived for predicting deflections without computing the effective moment of inertia. The ultimate deflections predicted by the proposed method correlated closely with the deflection under maximum bending moments. To calculate immediate deflections, variation functions for the concrete strain at the extreme compression fiber and neutral axis depth were assumed with predictions in good agreement with experiments. The proposed procedure has important implications in highlighting a new perspective on the deflection prediction of reinforced concrete and composite flexural members.

Sublimation of composite ice and its influence on performance of ice shells

2021 ◽  
Vol 36 (1) ◽  
pp. 67-77
Author(s):  
Yue Wu ◽  
Junkai Huang ◽  
Jiafeng Chen
Keyword(s):  
Numerical Simulation ◽  
Shell Structure ◽  
Composite Shell ◽  
Engineering Practice ◽  
Sublimation Rate ◽  
Long Span ◽  
Static Performance ◽  
New Type ◽  
Ice Sublimation ◽  
Composite Shell Structure

The long-span ice composite shell structure is a new type of ice and snow structure developed in recent years. The engineering practice of ice composite shell shows that sublimation is one of the important reasons for its damage and even collapse. In this paper, we firstly supplemented the existing H-K equation and obtained the revised ice sublimation equation through indoor evaporative plate experiment considering the influence of admixtures and wind speed. Afterwards, combining the simulations of solar radiation and CFD, the numerical simulation of sublimation distribution on the surface of were realized by programming in Grasshopper platform. During sublimation, the thickness of the ice composite shell decreases by 0.38 mm every 10 days and the sublimation rate on the sunny side was 1.7 times that on the shady side. Finally, the static performance and stability of the sublimated ice composite spherical shell were analyzed. After 70 days of sublimation, the thickness of the ice composite shell structure becomes thinner and uneven, which leads its sensitivity to external load increases.

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