Forward-Calculating Optimization Method for Determining the Rational Construction State of Cable-Stayed Bridges

2013 ◽  
Vol 671-674 ◽  
pp. 980-984 ◽  
Author(s):  
Sheng Jiang Sun ◽  
Jian Gao ◽  
Ping Ming Huang
Keyword(s):  
Programming Model ◽  
Optimization Method ◽  
Weighting Coefficient ◽  
Object Control ◽  
Cable Stayed Bridge ◽  
Calculating Method ◽  
Dead State ◽  
Optimization Calculation ◽  
Rational Construction ◽  
Cable Stayed Bridges

In order to determine every rational construction state and obtain perfect finished dead state of the cable-stayed bridge, a quadratic programming model for optimizing cable tension was put forward. The adjustment of multi-object control parameters was achieved by using the weighting coefficient in the optimization model. In the optimization calculation of a cable-stayed bridge, the forward-calculating method was used and the results show that mechanics concept of this method is definite, the rate of convergence is fast and some disadvantages of other methods are avoided.

The Reasonable Finished Dead State Research of Partially Earth-Anchored Cable-Stayed Bridge

2011 ◽  
Vol 255-260 ◽  
pp. 1319-1325 ◽  
Author(s):  
Li Wen Zhang ◽  
Rui Jie Xia
Keyword(s):  
Adjustment Process ◽  
Influence Matrix ◽  
Cable Stayed Bridge ◽  
Dead State ◽  
State Research ◽  
Secondary Stage ◽  
Beam Method ◽  
Cable Force ◽  
Mechanics Characteristics ◽  
Cable Stayed Bridges

Based on the mechanics characteristics of partially earth-anchored cable-stayed bridge, the criterion of reasonable finished dead state was presented. The effect factors considered include: the distribution of cable force, the inner force of girder and tower, the dimension of earth-anchor, and the displacement of tower top. Combined with methods to determine cable force of traditional self-anchored cable-stayed bridges in reasonable completed status, a two-stage method was used to find the cable force of these bridges which was divided into finding the initial cable force with rigid supported continuous beam method and then fix on the final optimized cable force in the reasonable completed status through adjusting the initial cable force in first stage with influence matrix method. And the adjustment process of cable force in secondary stage was proposed based on the mechanics characteristics of these bridges. Finally, a calculation was carried out for a partially earth-anchored cable-stayed bridge with 1218m main span and composite beam. The result shows that this method was logical, practical convenient and efficient. And the cable force in the reasonable completed status of bridges can be obtained faster according to the adjustment process of cable force in secondary stage.

scholarly journals Multiobjective Optimization of Cable Forces and Counterweights for Universal Cable-Stayed Bridges

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Zhangming Wang ◽  
Nan Zhang ◽  
Xianting Du ◽  
Shilei Wang ◽  
Qikai Sun
Keyword(s):  
Optimal Solution ◽  
Optimization Method ◽  
Solution Set ◽  
Spatial Effects ◽  
Pareto Solution ◽  
Cable Stayed Bridge ◽  
Optimal Solution Set ◽  
Cable Forces ◽  
Coefficient Method ◽  
Cable Stayed Bridges

In cable-stayed bridges, especially asymmetric bridges, counterweights are always made to work together with cable pretension forces to get a reasonable finished state. To solve the optimization problem of the cable-stayed bridge considering the counterweights, the integrated optimization method (IOM) for estimating cable forces and counterweights is proposed. In this method, the counterweights are proposed to act on the anchor points. After that, the summary of the minimum weighted total bending energy and the summary of the counterweights are considered as two objective functions of a multiobjective problem. Finally, the dynamic weighted coefficient method is used to solve this problem and realize the Pareto solution set. IOM presents detailed procedures in a simple numerical model and is then applied to the Yong-ding special-shaped cable-stayed bridge. The results show that not only IOM can realize the priority selection of the loading position of the counterweights but also get a better reasonable finish state because of the introduction of the counterweight dimension; the dynamic weighted coefficient method can quickly find the Pareto optimal solution set and be further screened by decision-makers; counterweight is very helpful to reduce torsion and other spatial effects in cable-stayed bridges. IOM can be used as a universal optimization method for cable-stayed bridges.

scholarly journals PROBABILITY MODEL AND RELIABILITY ANALYSIS OF CABLE STRESS FOR CABLE-STAYED BRIDGE

2017 ◽  
Vol 12 (4) ◽  
pp. 248-257
Author(s):  
Xiao-Yan Yang ◽  
Jin-Xin Gong ◽  
Yin-Hui Wang ◽  
Bo-Han Xu ◽  
Ji-Chao Zhu
Keyword(s):  
Lognormal Distribution ◽  
Reliability Index ◽  
Probability Model ◽  
Time Interval ◽  
Stay Cable ◽  
Cable Stayed Bridge ◽  
Dead State ◽  
Vehicle Load ◽  
Crossing Theory ◽  
Cable Stayed Bridges

The aim of this paper is to investigate the time-varying effect of stay cable of long-span cable-stayed bridges subject to vehicle load. The analysis has been carried out on the Su-Tong cable-stayed bridge in Jiangsu, China that has the second-longest span among the completed composite-deck cable-stayed bridges in the world currently. Probability models of vehicle load in each lane (fast lane, middle lane and slow lane) and cable stress under random vehicle load were developed based on the stochastic process theory. The results show the gross vehicle weight follows lognormal distribution or multi-peak distribution, and the time-interval of the vehicle follows a lognormal distribution. Then, the probability function of maximum cable stress was determined using up-crossing theory. Finally, the reliability of stay cable under random vehicle load was analysed. The reliability index ranges from 9.59 to 10.82 that satisfies the target reliability index of highway bridge structure of finished dead state.

scholarly journals Optimization of Cable Force Adjustment in Cable-Stayed Bridge considering the Number of Stay Cable Adjustment

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Han-Hao Zhang ◽  
Nan-Nan Sun ◽  
Pei-Zhi Wang ◽  
Man-Hui Liu ◽  
Yuan Li
Keyword(s):  
Sensitivity Analysis ◽  
Calculation Method ◽  
Maintenance Phase ◽  
Optimization Method ◽  
Stay Cable ◽  
Stay Cables ◽  
Design Variables ◽  
Optimization Calculation ◽  
Cable Force ◽  
Cable Stayed Bridges

Modern cable-stayed bridges are spatial, multicable systems. The cable force needs to be adjusted during the construction phase and maintenance phase. The existing calculation methods of cable force adjustment mainly considered the rationality of structural force, but only few research studies have been conducted on how to reduce the number of stay cables which need to be adjusted. This study aims to propose an optimization calculation method including the optimization module with the sensitivity analysis and updating design variable module (UDVM), which are used for cable force adjustment in cable-stayed bridges. Based on the finite difference method, the sensitivity analysis is adopted in the optimization module, which can capture the response of structures as design variables vary; the particle swarm optimization method is adopted for structural optimization. The proposed method can dramatically reduce the number of stay cables which need to be adjusted and ensure the main girder stresses remain in a reasonable state during stay cable adjustment progress by UDVM. Moreover, the proposed method can continuously update the objective function, constraint conditions, and design variables. Finally, this proposed optimization calculation method is applied to two different cable-stayed bridges to validate the reliability and feasibility of the method.

scholarly journals Optimal Placement and Sizing of D-STATCOM in Radial and Meshed Distribution Networks Using a Discrete-Continuous Version of the Genetic Algorithm

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1452
Author(s):  
Cristian Mateo Castiblanco-Pérez ◽  
David Esteban Toro-Rodríguez ◽  
Oscar Danilo Montoya ◽  
Diego Armando Giral-Ramírez
Keyword(s):  
Genetic Algorithm ◽  
Objective Function ◽  
Programming Model ◽  
Distribution Networks ◽  
Optimization Method ◽  
Optimal Placement ◽  
Mixed Integer ◽  
Power Balance ◽  
Continuous Version ◽  
Discrete Part

In this paper, we propose a new discrete-continuous codification of the Chu–Beasley genetic algorithm to address the optimal placement and sizing problem of the distribution static compensators (D-STATCOM) in electrical distribution grids. The discrete part of the codification determines the nodes where D-STATCOM will be installed. The continuous part of the codification regulates their sizes. The objective function considered in this study is the minimization of the annual operative costs regarding energy losses and installation investments in D-STATCOM. This objective function is subject to the classical power balance constraints and devices’ capabilities. The proposed discrete-continuous version of the genetic algorithm solves the mixed-integer non-linear programming model that the classical power balance generates. Numerical validations in the 33 test feeder with radial and meshed configurations show that the proposed approach effectively minimizes the annual operating costs of the grid. In addition, the GAMS software compares the results of the proposed optimization method, which allows demonstrating its efficiency and robustness.

scholarly journals Effect of blast loading and resulting progressive failure of a cable-stayed bridge

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Ravi Mudragada ◽  
S. S. Mishra
Keyword(s):  
Progressive Failure ◽  
Blast Resistance ◽  
Progressive Collapse ◽  
Building Structures ◽  
Structural Elements ◽  
Blast Loads ◽  
Cable Stayed Bridge ◽  
Bridge Performance ◽  
Cable Stayed Bridges

AbstractMany researchers have carried out experimental and numerical investigations to examine building structures’ response to explosive loads. Studies of bridges subjected to blast loads are limited. Hence, in this study, we present a case study on a cable-stayed bridge, namely, Charles River Cable-Stayed Bridge-Boston, to assess its robustness and resistance against the progressive collapse resulting from localized failure due to blast loads. Three different blast scenarios are considered to interpret the bridge performance to blast loads. To monitor the progressive failure mechanisms of the structural elements due to blast, pre-defined plastic hinges are assigned to the bridge deck. The results conclude that the bridge is too weak to sustain the blast loads near the tower location, and the progressive collapse is inevitable. Hence, to preserve this cable-stayed bridge from local and global failure, structural components should be more reinforced near the tower location. This case study helps the designer better understand the need for blast resistance design of cable-stayed bridges.

Study on the Effective Slab Width of Composite Cable-Stayed Bridge under Axial Force

2012 ◽  
Vol 568 ◽  
pp. 200-203
Author(s):  
Xiang Nan Wu ◽  
Xiao Liang Zhai ◽  
Ming Min Zhou
Keyword(s):  
Axial Force ◽  
Shear Lag ◽  
Distribution Law ◽  
Slab Width ◽  
Cable Stayed Bridge ◽  
Stay Cables ◽  
Transmission Angle ◽  
Effective Flange Width ◽  
Width Coefficient ◽  
Cable Stayed Bridges

There exist evident shear-lag phenomena in large-span composite cable-stayed bridges under the action of axial force, especially in the deck with double main girders. In order to discuss the distribution law of the effective flange width coefficient along the span, caused by axial force, finite element computations of five composite cable-stayed bridges and theoretical analysis have been performed. The transmission angle of axial force caused by the axial compression of stay cables was given, meanwhile the formulas for computation effective slab width coefficient under axial force were suggested.

A prediction method for cable forces of cable-stayed bridges using fuzzy processing and Bayes estimation

2021 ◽  
Author(s):  
Li Dong ◽  
Bin Xie ◽  
Dongli Sun ◽  
Yizhuo Zhang
Keyword(s):  
Prediction Method ◽  
Practical Method ◽  
Bayes Estimation ◽  
Primary Data ◽  
Force Estimation ◽  
Element Analysis ◽  
Cable Stayed Bridge ◽  
Input Parameters ◽  
Cable Forces ◽  
Cable Stayed Bridges

<p>Cable forces are primary factors influencing the design of a cable-stayed bridge. A fast and practical method for cable force estimation is proposed in this paper. For this purpose, five input parameters representing the main characteristics of a cable-stayed bridge and two output parameters representing the cable forces in two key construction stages are defined. Twenty different representative cable-stayed bridges are selected for further prediction. The cable forces are carefully optimized through finite element analysis. Then, discrete and fuzzy processing is applied in data processing to improve their reliability and practicality. Finally, based on the input parameters of a target bridge, the maximum possible output parameters are calculated by Bayes estimation based on the processed data. The calculation results show that the average prediction error of this method is less than 1% for the twenty bridges themselves, which provide the primary data and less than 3% for an under-construction bridge.</p>

An Interval-Index-Oriented Intelligent Optimization Method and its Industrial Application

2011 ◽  
Vol 219-220 ◽  
pp. 546-550
Author(s):  
Ming Shan Cai ◽  
Ling Shuang Kong
Keyword(s):  
Optimal Control ◽  
Industrial Application ◽  
Programming Model ◽  
Optimization Method ◽  
Quality Indices ◽  
Reasoning Strategy ◽  
Goal Programming Model ◽  
Interval Goal Programming ◽  
Expert Reasoning

Based on the strong coupling and interval requirement of multiple quality indices, the interval-index-oriented optimization method is proposed to effectively realize the optimal control of alumina blending process. Firstly, the lexicographic interval goal programming model is built to describe the process requirements for quality indices. Then, based on the characteristics of the programming model, a kind of classificatory knowledge base is constructed by using the empirical knowledge accumulated in long-term production and the expert reasoning strategy is proposed to realize the optimal control of quality indexes with interval constraints. The results of industrial application shows that the proposed method can realize the optimal control of quality indices. It provides a good optimization mode for other blending processes of nonferrous metal production.

GA-CDFM Based Hybrid Optimization Method for Steelmaking Scheduling and Caster Operation

2012 ◽  
Vol 424-425 ◽  
pp. 994-998 ◽  
Author(s):  
Xiao Chuan Luo ◽  
Chong Zheng Na
Keyword(s):  
Genetic Algorithm ◽  
Integer Programming ◽  
Mixed Integer Programming ◽  
Programming Model ◽  
Optimization Method ◽  
Optimal Performance ◽  
Hybrid Optimization ◽  
Mixed Integer ◽  
Algorithm Optimization ◽  
Genetic Algorithm Optimization

In steelmaking plant, the process times of machines change frequently and randomly for the reason of metallurgical principle. When those change happen, the plant scheduling and caster operation must respond to keep the optimal performance profile of plant. Therefore, the integration of plant scheduling and caster operation is a crucial task. This paper presents a mixed-integer programming model and a hybrid optimized algorithm for caster operation and plant scheduling, which combine the genetic algorithm optimization and CDFM process status verification. Data experiments illustrate the efficiency of our model and algorithm.

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