Search results

1 – 10 of 31
To view the access options for this content please click here
Article
Publication date: 12 November 2019

Zhen Li, Dejian Li, Yao Lu, Kepei Cheng and Qianqiu Wu

The purpose of this paper is to obtain the response time history curves of vertical and lateral acceleration in the span of the main beam under different loads through the…

Abstract

Purpose

The purpose of this paper is to obtain the response time history curves of vertical and lateral acceleration in the span of the main beam under different loads through the finite element time-history analysis method, so as to realize the Serviceability Analysis of a Cable-Supported Footbridge Subjected to Human-Induced Loads, taking the long-span cable-supported footbridge over Dongtan River as an example.

Design/methodology/approach

The finite element method is used for analysis of the footbridge.

Findings

It is found that under the condition of low-density pedestrians walking freely, the response of human vertical vibration acceleration and the load conditions of pedestrian overpasses cannot meet the requirements of normal use. Therefore, the vertical acceleration of the footbridge should be designed to reduce vibration. Under these two loading conditions, the lateral acceleration response meets the requirements of normal use.

Originality/value

On the basis of summarizing the research at home and abroad, the analysis of human-induced vibration is mainly considered from two aspects: frequency regulation and dynamic response control. The walking load models mainly include Fourier series model, self-excitation model, impulse model, stochastic model and more; the crowd load models are divided into groups: low-density crowd walking freely, high-density crowd flowing and more. Therefore, it is very important to calculate the structural vibration response in the design of long-span cable-supported footbridges under pedestrian excitation to meet comfort requirements.

Details

International Journal of Structural Integrity, vol. 11 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

To view the access options for this content please click here
Article
Publication date: 7 January 2019

Jiandong Wei, Manyu Guan, Qi Cao and Ruibin Wang

The purpose of this paper is to analyze the cable-supported bridges more efficiently by building the finite element model with the spatial combined cable element.

Abstract

Purpose

The purpose of this paper is to analyze the cable-supported bridges more efficiently by building the finite element model with the spatial combined cable element.

Design/methodology/approach

The spatial combined cable element with rigid arms and elastic segments was derived. By using the analytical solution of the elastic catenary to establish the flexibility matrix at the end of the cable segment and adding it to the flexibility matrix at the ends of the two elastic segments, the flexibility matrix at the end of the cable body is obtained. Then the stiffness matrix of the cable body is established and the end force vector of cable body is given. Using the displacement transformation relationship between the two ends of the rigid arm, the stiffness matrix of the combined cable element is derived. By assigning zero to the length of the elastic segment(s) or/and the rigid arm(s), many subdivisions of the combined cable element can be obtained, even the elastic catenary element.

Findings

The examples in this field and specially designed examples proved the correctness of the proposed spatial combined cable element.

Originality/value

The combined cable element proposed in this study can be used for the design and analysis of cable-stayed bridges. Case studies show that it is able to simulate cable accurately and could also be used to simulate the suspenders in arch bridges as well in suspension bridges.

Details

Engineering Computations, vol. 36 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 7 March 2008

Wei‐Xin Ren, Hao‐Liang Liu and Gang Chen

Owing to the cable flexibility, it is practically a lot easier to measure the high‐vibration frequencies of the cable than the fundamental vibration frequency. The…

Downloads
1025

Abstract

Purpose

Owing to the cable flexibility, it is practically a lot easier to measure the high‐vibration frequencies of the cable than the fundamental vibration frequency. The objective of this study is to present a method to determine the cable tension based on frequency differences so that the effects of cable sag and bending stiffness can be included.

Design/methodology/approach

The paper includes theoretical derivation, laboratory study to verify the method and practical application in a real bridge.

Findings

It is suggested to measure the high‐vibration frequencies, and to use the vibration frequency difference to determine the fundamental vibration frequency of the cable and then to estimate the cable tension. The reliability of the method is verified by laboratory tests and the method is then applied to determine cable tensions in a real bridge.

Originality/value

This paper provides theoretical derivations to demonstrate that under certain conditions, the frequency difference of a cable with sag and bending is almost equal to the natural frequency of the same cable when it is taut. This unique characteristic of cable vibration is used to determine the cable tension similar to the fundamental frequency‐based taut‐string formula that is commonly used in practice.

Details

Engineering Computations, vol. 25 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 27 May 2014

Ming-Yi Liu, Li-Chin Lin and Pao-Hsii Wang

The purpose of this paper is to provide a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of…

Abstract

Purpose

The purpose of this paper is to provide a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure.

Design/methodology/approach

Based on the smooth and convergent bridge shapes obtained by the initial shape analysis, the one-element cable system (OECS) and multi-element cable system (MECS) models of the symmetric harp cable-stayed bridge are developed to verify the applicability of the analytical model and numerical formulation from the field observations in the authors’ previous work. For this purpose, the modal analyses of the two finite element models are conducted to calculate the natural frequency and normalized mode shape of the individual modes of the bridge. The modal coupling assessment is also performed to obtain the generalized mass ratios among the structural components for each mode of the bridge.

Findings

The findings indicate that the coupled modes are attributed to the frequency loci veering and mode localization when the “pure” deck-tower frequency and the “pure” stay cable frequency approach one another, implying that the mode shapes of such coupled modes are simply different from those of the deck-tower system or stay cables alone. The distribution of the generalized mass ratios between the deck-tower system and stay cables are useful indices for quantitatively assessing the degree of coupling for each mode. For each identical group of stay cables in the MECS model, the local modes with similar natural frequencies and normalized mode shapes consist of the participation of one or more stay cables. These results are demonstrated to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges.

Originality/value

It is important to investigate the deck-stay interaction with the appropriate initial shape of a cable-stayed bridge. This is because such initial shape not only reasonably provides the geometric configuration as well as the prestress distribution of the bridge under the weight of the deck-tower system and the pretension forces in the stay cables, but also definitely ensures the satisfaction of the relations for the equilibrium conditions, boundary conditions and architectural design requirements. However, few researchers have studied the deck-stay interaction considering the initial shape effect. The objective of this paper is to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges, which is validated by a symmetrical structure. The modal coupling assessment is also performed for quantitatively assessing the degree of coupling for each mode of the bridge.

Details

Engineering Computations, vol. 31 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 30 May 2008

Wei‐Xin Ren, Meng‐Gang Huang and Wei‐Hua Hu

The purpose of this paper is to present a finite element formulation of enhanced two‐node parabolic cable element for the static analysis of cable structures.

Downloads
1720

Abstract

Purpose

The purpose of this paper is to present a finite element formulation of enhanced two‐node parabolic cable element for the static analysis of cable structures.

Design/methodology/approach

Unlike the assumed polynomial displacement interpolation functions, the present approach uses the analytical cable dynamic stiffness matrix to obtain the explicit expression of the static stiffness matrix of an inclined sagging cable by setting the frequency at zero. The Newton‐Raphson‐based iterative method is used to obtain the solution.

Findings

It is demonstrated that the present results agree well with those obtained from the nonlinear analytical theory of a parabolic cable and previous reported methods in the literature.

Originality/value

This paper proposes a two‐node parabolic cable element. For comparable accuracy with the truss element method, fewer numbers of such cable elements are needed.

To view the access options for this content please click here
Article
Publication date: 1 September 1966

ROAD ACCESS between South Wales and Southern England has been notable for its inadequacy even in the notoriously poor road system of Britain. Two major problems are the…

Abstract

ROAD ACCESS between South Wales and Southern England has been notable for its inadequacy even in the notoriously poor road system of Britain. Two major problems are the Severn estuary and valley, which runs inland north‐easterly to form a natural barrier between the two areas, and the enormous growth of traffic. South Wales has developed considerably as an industrial area, and a large volume of industrial and commercial road vehicles, combined with commuting and heavy tourist traffic is channelled through Gloucester, via a narrow bridge, and the cramped hilly streets of Chepstow, where the popular race meetings periodically help to bring road communication to a standstill.

Details

Anti-Corrosion Methods and Materials, vol. 13 no. 9
Type: Research Article
ISSN: 0003-5599

To view the access options for this content please click here
Article
Publication date: 3 July 2017

Pengzhen Lu, Hua Shao and Jian Ting Cheng

The purpose of this paper is to develop a simplified optimization calculation method to assess cable force of self-anchored suspension bridge based on optimization theories.

Downloads
131

Abstract

Purpose

The purpose of this paper is to develop a simplified optimization calculation method to assess cable force of self-anchored suspension bridge based on optimization theories.

Design/methodology/approach

A simplified analysis method construction using Matlab is developed, which is then compared with the optimization method that considers the main cable’s geometric nonlinearity with software ANSYS in an actual bridge calculation.

Findings

This contrast proves the weak coherence and the adjacently interaction theory unreasonable and its limitation.

Originality/value

This paper analyzes the calculation method to assess cable force of a self-anchored suspension bridge and its application effect.

Details

Engineering Computations, vol. 34 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 1 February 1977

S. Balachandran

Civil engineering encompasses such a wide array of subject areas that it would be very difficult to cover all of them in one survey. Basically, civil engineers are…

Abstract

Civil engineering encompasses such a wide array of subject areas that it would be very difficult to cover all of them in one survey. Basically, civil engineers are concerned with the planning, design and construction of buildings, transporation facilities and other structures required for human health, safety and welfare. A major part of their job relates to achieving a coherent relationship between the “built environment” and the “natural environment.” They are required to fulfil this function within the framework of constraints imposed by the present day building codes, union regulations and economic considerations. This survey concerns itself mostly with the general civil engineering reference books and some selected sources on specialized topics like construction engineering, foundation engineering, structural engineering, highway and dam engineering and codes and specifications. A forthcoming survey will deal with the major area of environmental and sanitary engineering.

Details

Reference Services Review, vol. 5 no. 2
Type: Research Article
ISSN: 0090-7324

To view the access options for this content please click here
Article
Publication date: 28 September 2021

Yao Lu, Dejian Li, Kai Wang and Zhen Li

Over-limit transportation has the characteristics of large axle load, large number of axles and lateral distribution width. Under the action of over-limit load, the…

Abstract

Purpose

Over-limit transportation has the characteristics of large axle load, large number of axles and lateral distribution width. Under the action of over-limit load, the coupling vibration effect of vehicle–bridge is more obvious, and the deformation of bridge components is large. Thus, research and analysis of the vehicle–bridge coupling dynamic response of long-span bridges under over-limit transportation has practical engineering significance.

Design/methodology/approach

Based on the principle of invariable elastic potential energy, this paper derives dynamic model of over-limit transportation n-axis flat vehicle. The numerical simulation method is used to model and calculate a cable-stayed bridge, and the static effect of the cable-stayed bridge and the dynamic response of vehicle–bridge coupling under different parameters are compared and analyzed.

Findings

The focus is on the influence of vehicle load and vehicle velocity parameters on the stress and amplitude of different cables under over-limit transportation, and the corresponding variation law is obtained.

Originality/value

The research on the coupled dynamic response of cable-stayed bridges has attracted the attention of many scholars, but there are relatively few studies on the coupled vibration of out-limit vehicles and bridges. In this paper, based on finite element software, a vehicle–bridge coupling model under bulk transportation is established.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

Keywords

To view the access options for this content please click here
Article
Publication date: 30 September 2014

Kun Cai, Zhen Luo and Qing H. Qin

The purpose of this paper is to develop a heuristic method for topology optimization of a continuum with bi-modulus material which is frequently occurred in practical…

Abstract

Purpose

The purpose of this paper is to develop a heuristic method for topology optimization of a continuum with bi-modulus material which is frequently occurred in practical engineering.

Design/methodology/approach

The essentials of this model are as follows: First, the original bi-modulus is replaced with two isotropic materials to simplify structural analysis. Second, the stress filed is adopted to calculate the effective strain energy densities (SED) of elements. Third, a floating reference interval of SED is defined and updated by active constraint. Fourth, the elastic modulus of an element is updated according to its principal stresses. Final, the design variables are updated by comparing the local effective SEDs and the current reference interval of SED.

Findings

Numerical examples show that the ratio between the tension modulus and the compression modulus of the bi-modulus material in a structure has a significant effect on the final topology design, which is different from that in the same structure with isotropic material. In the optimal structure, it can be found that the material points with the higher modulus are reserved as much as possible. When the ratio is far more than unity, the material can be considered as tension-only material. If the ratio is far less than unity, the material can be considered as compression-only material. As a result, the topology optimization of continuum structures with tension-only or compression-only materials can also be solved by the proposed method.

Originality/value

The value of this paper is twofold: the bi-modulus material layout optimization in a continuum can be solved by the method proposed in this paper, and the layout difference between the structure with bi-modulus material and the same structure but with isotropic material shows that traditional topology optimization result could not be suitable for a real bi-modulus layout design project.

Details

Engineering Computations, vol. 31 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

1 – 10 of 31