scholarly journals Refined Finite Element Analysis of Crack Causes in SRC Arch Rib Bridges considering Multiple Factors

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Mengsheng Yu ◽  
Nianchun Deng ◽  
Qifeng Chen ◽  
Tianzhi Hao
Keyword(s):  
Steel Frame ◽  
Element Analysis ◽  
Shrinkage Temperature ◽  
Arch Bridge ◽  
Temperature Changes ◽  
Concrete Shrinkage ◽  
Shrinkage Process ◽  
Crack Problems ◽  
Arch Bridges ◽  
Bearing Structure

The SRC (steel-frame reinforced concrete) arch bridge is an important part of the development of arch bridges. Scholars worldwide have studied it from various aspects because of its stronger stiffness and stability than other types of bridges especially when crossing the canyon. The steel frame is a stress bracket during construction. Concrete becomes the main axial-pressure bearing structure when it fills the inner pipe and the encased frame. This article mainly focuses on the crack problems of SRC arch bridging during the postconstruction operation, local model of the midspan arch rib, and the equivalent relationship between the coefficient of expansion and the temperature of concrete. This study uses a cooling method to simulate the shrinkage process with detailed analysis of three properties including concrete shrinkage, temperature gradients, and concentrated hanger rod force. It is concluded that the SRC arch bridge will have large tensile stress on both inner and outer surfaces of slab and web when the temperature changes, and it is the main cause of cracks. The results agree well with measured data. At last, we come up with some reference suggestions in the design and construction of similar bridges in the future.

Experimental Research and Finite Element Analysis on Behavior of Steel Frame with Semi-Rigid Connections

2010 ◽  
Vol 168-170 ◽  
pp. 553-558
Author(s):  
Feng Xia Li ◽  
Bu Xin
Keyword(s):  
Architectural Design ◽  
Plastic Hinge ◽  
Steel Frames ◽  
Seismic Energy ◽  
Internal Force ◽  
Steel Frame ◽  
Frame Structure ◽  
Element Analysis ◽  
Rigid Deformation ◽  
Steel Frame Structure

Most steel beam-column connections actually show semi-rigid deformation behavior that can contribute substantially to overall displacements of the structure and to the distribution of member forces. Steel frame structure with semi-rigid connections are becoming more and more popular due to their many advantages such as the better satisfaction with the flexible architectural design, low inclusive cost and environmental protect as well. So it is very necessary that studying the behavior of those steel frame under cyclic reversal loading. On the basics of connections experiments the experiment research on the lateral resistance system of steel frame structure has been completed. Two one-second scale, one-bay, two-story steel frames with semi-rigid connections under cyclic reversal loading. The seismic behavior of the steel frames with semi-rigid connections, including the failure pattern, occurrence order of plastic hinge, hysteretic property and energy dissipation, etc, was investigated in this paper. Some conclusions were obtained that by employing top-mounted and two web angles connections, the higher distortion occurred in the frames, and the internal force distributing of beams and columns was changed, and the ductility and the absorbs seismic energy capability of steel frames can be improved effectively.

Heat Transfer and Thermal Stress Analysis of an Optoelectronic Package

1991 ◽  
Vol 113 (3) ◽  
pp. 258-262 ◽  
Author(s):  
J. G. Stack ◽  
M. S. Acarlar
Keyword(s):  
Heat Transfer ◽  
Thermal Management ◽  
Power Dissipation ◽  
Point Of View ◽  
Optical Data ◽  
Data Link ◽  
Element Analysis ◽  
Thermally Induced ◽  
Temperature Changes ◽  
Induced Stresses

The reliability and life of an Optical Data Link transmitter are inversely related to the temperature of the LED. It is therefore critical to have efficient packaging from the point of view of thermal management. For the ODL® 200H devices, it is also necessary to ensure that all package seals remain hermetic throughout the stringent military temperature range requirements of −65 to +150°C. For these devices, finite element analysis was used to study both the thermal paths due to LED power dissipation and the thermally induced stresses in the hermetic joints due to ambient temperature changes

Novel Hanger Design to Improve the Robustness of Through Arch Bridges

2011 ◽  
Vol 90-93 ◽  
pp. 862-868
Author(s):  
Qi Ming Wu ◽  
Dang Qi Yang ◽  
Fei Cui ◽  
Xiao Wei Yi ◽  
Rui Juan Jiang
Keyword(s):  
Progressive Collapse ◽  
Time History ◽  
Structural Members ◽  
New Approach ◽  
Arch Bridge ◽  
Structural Robustness ◽  
Arch Bridges ◽  
Dynamic Time ◽  
The Impact ◽  
Emergency Measures

Hangers in through arch bridges are important components since they suspend the bridge deck from the arch ribs. Local damage at a hanger may lead to progressive damage of various components in the arch bridge or even progressive collapse of the bridge. In this paper, the conventional design of double-hangers in through arch bridges is reviewed. Then a new approach to design the double-hangers is put forward. The suitability and robustness of this approach is then verified by a numerical simulation of a real through arch bridge. The impact effects induced by local hanger fracture on other structural members are simulated by dynamic time-history analyses. The new approach to design the hangers for through arch bridges is shown to improve the structural robustness. With the application of the new way put forward here, when one or more hangers are damaged to fail, the through arch bridge will not be endangered and will still maintain the overall load-bearing capacity during an appropriate length of time to allow necessary emergency measures to be taken, which illustrates the leading principle of structural robustness well.

Study on Reliability Evaluation Method of Existing CFST Arch Bridge

2012 ◽  
Vol 226-228 ◽  
pp. 1679-1682
Author(s):  
Yi Song Zou ◽  
Hai Tao Hou ◽  
Wei Peng
Keyword(s):  
System Reliability ◽  
Reliability Index ◽  
Evaluation Method ◽  
Reliability Assessment ◽  
Steel Tube ◽  
Arch Bridge ◽  
Cfst Arch Bridge ◽  
Arch Bridges ◽  
Grading Standards ◽  
Bridge System

Based on reliability theory, the application calculation method of Concrete Filled Steel Tube (CFST) arch bridge system reliability index is studied. Select the most unfavorable load distribution in working condition of maximum moment and deflection at the mid-span, from the angle of strain energy, calculated the weights of CFST arch ribs component. On the basis of the grading standards of reliability assessment of the existing bridge components and the critical structures, CFST arch bridge system reliability assessment grading standards are constructed. CFST arch bridges reliability index are evaluated from two aspects (the arch ribs and segment) in this article. As the CFST arch bridge locates in the marine environment, corrosion environment is the serious level of C5-M, steel pipe corrosion is the major diseases of CFST, arch rib which on the corrosion conditions were assessed. The results show that the method can effectively assess the situation of CFST arch bridge.

scholarly journals The Linear Hygroscopic Expansion Coefficient of Cement-Based Materials and Its Determination

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 37
Author(s):  
Depeng Chen ◽  
Qilin Zhu ◽  
Zhifang Zong ◽  
Tengfei Xiang ◽  
Chunlin Liu
Keyword(s):  
Finite Element ◽  
Drying Shrinkage ◽  
Simple Calculation ◽  
Thermal Shrinkage ◽  
Element Analysis ◽  
Concrete Shrinkage ◽  
Temperature Load ◽  
Cement Based Materials ◽  
The Common ◽  
Inversion Analysis

A crack caused by shrinkage could remarkably increase the permeability, heavily deteriorate the durability, and heavily deteriorate the service life of a concrete structure. However, different forms of thermal shrinkage can be predicted by directly applying a temperature load on a node. The prediction of moisture-induced stresses in cement-based materials by using the common finite element method (FEM) software is a big challenge. In this paper, we present a simple numerical calculation approach by using the proposed coefficient of hygroscopic expansion (CHE) to predict the moisture-induced deformation of concrete. The theoretical calculation formula of the linear CHE (LCHE) of cement-based material was deduced based on the Kelvin–Laplace equation and the Mackenzie equation. The hygroscopic deformation of cement mortar was investigated by inversion analysis; based on the results, the LCHE could be determined. Moreover, a case analysis of the application of LCHE to concrete is also conducted. The simulated results of concrete shrinkage were close to the experimental ones. As a whole, it is feasible to predict the drying shrinkage of concrete through simple calculation by using the proposed LCHE, which is also beneficial to the direct application of moisture loads on nodes in finite element analysis (FEA).

Study of Reinforcing Mechanism of Rigid-Frame Arch Bridge Based on Static and Dynamic Analysis

2011 ◽  
Vol 219-220 ◽  
pp. 458-462
Author(s):  
Ze Ying Yang ◽  
Xi Bin Zhang ◽  
Jian Bo Qu
Keyword(s):  
Dynamic Properties ◽  
Element Model ◽  
Reinforcement Scheme ◽  
Arch Bridge ◽  
3 Dimensional ◽  
Static And Dynamic Analysis ◽  
Rigid Frame ◽  
Dimensional Finite Element ◽  
Arch Bridges ◽  
The Relationship

According to Dawenkou bridge, a seriously deteriorated rigid-frame arch bridge, typical deteriorations of rigid-frame arch bridges were summarized. Based on 3-dimensional finite element model of a rigid-frame arch bridge, the relationship between dynamic properties and deteriorations of the structure, especially the influence of lateral tie system on the dynamic properties of the structure was analyzed. The results show that, damages of lateral tie system in operation induced premature appearance of lateral vibration directly; however, the large curvature torsion of deck obviously should take the mainly responsibility of damages of lateral tie system. According to the above analysis, the corresponding reinforcement scheme and specific measures were proposed.

Risk Analysis for the Construction Phases of Long-Span CFST Arch Bridge Based on Finite Element Analysis

2011 ◽  
Vol 225-226 ◽  
pp. 823-826
Author(s):  
Yu Feng Zhang ◽  
Guo Fu Sun
Keyword(s):  
Finite Element ◽  
Risk Analysis ◽  
Limit State ◽  
Ultimate Limit State ◽  
Element Analysis ◽  
Nonlinear Buckling ◽  
Finite Element Program ◽  
Arch Bridge ◽  
Cfst Arch Bridge ◽  
Element Program

As a part of virtual simulation of construction processes, this paper deals with the quantitative risk analysis for the construction phases of the CFST arch bridge. The main objectives of the study are to evaluate the risks by considering an ultimate limit state for the fracture of cable wires and to evaluate the risks for a limit state for the erection control during construction stages. Many researches have been evaluated the safety of constructed bridges, the uncertainties of construction phases have been ignored. This paper adopts the 3D finite element program ANSYS to establish the space model of CFST Arch Bridge, and to calculate the linear, the geometrical nonlinear and the double nonlinear buckling safety factors under the six different lode cases. Then the bridge’s risks are evaluated according to the results calculated which provide a reference for design of similar project.

Sign in / Sign up

Export Citation Format

Share Document