scholarly journals THEORETICAL ANALYSIS OF DYNAMIC RESPONSE OF A BRIDGE SECTION LOADING BY THE IMPULSIVE FORCE

2017 ◽  
Vol 18 (2) ◽  
Author(s):  
ADRIAN LEOPA
Keyword(s):  
Dynamic Response ◽  
Seismic Design ◽  
Mathematical Theory ◽  
Structural Integrity ◽  
Road Traffic ◽  
Physical Models ◽  
General Nature ◽  
Impulsive Force ◽  
Dynamic Insulation ◽  
Bridge Structures

<p>The work in seismic design of bridges is needed to develop physical models and mathematical theory, based on which will be assessed and quantified the dynamic response of bridge structures subjected to stress arising from road traffic or seismic activity.</p><p>The need for this modeling is imposed three requirements: to ensure the structural integrity of the bridge elements for subjected impulsive, proper choice of dynamic insulation elements placed as a interface between the superstructure and infrastructure, as well as analysis of effects on joints in these situations demand. This paper proposes a physical model of a general nature, enabling customization depending on the specific constructive bridge, or the way it is solicited. Customize this model was developed for this study based on the existing viaduct Transylvania highway located between km 29 +602.75 and km 29 +801.25.</p>

DYNAMIC RESPONSE OF TIMBER BRIDGES AS A TOOL TO MEASURE STRUCTURAL INTEGRITY

2003 ◽  
Vol 27 (3) ◽  
pp. 25-28
Author(s):  
A.M. Morison ◽  
C.D. Karsen ◽  
H.A. Evensen ◽  
J.B. Ligon
Keyword(s):  
Dynamic Response ◽  
Structural Integrity ◽  
Timber Bridges

A theoretical analysis of congestion in a two-lane freeway

1970 ◽  
Vol 7 (2) ◽  
pp. 304-315
Author(s):  
Donald R. Mcneil
Keyword(s):  
Theoretical Analysis ◽  
Statistical Mechanics ◽  
Mathematical Theory ◽  
Road Traffic ◽  
Unified Theory ◽  
Conservation Of Mass ◽  
Limited Class

To current workers in the mathematical theory of road traffic, one of the most challenging and important problems is to describe and analyze the congestion suffered by motorists on freeways. While there is, as yet, no satisfactory unified theory, several different models have been suggested, each of which is reasonable for a limited class of situations. These approaches fall largely into two categories. The first may be described as looking at traffic “in the large” and its principal exponents were Lighthill and Whitham (1955) and Prigogine (1961). The theory of Lighthill and Whitham involves treating the system of vehicles as a fluid subject to a rule of conservation of mass (that is, vehicles) and an assumed relation between the flow and concentration at each point. This theory is completely deterministic. Prigogine's approach is to regard the system of vehicles as behaving like the particles in a gas and subject to the laws of statistical mechanics.

Fire of steel and composite beam bridges

2019 ◽  
Author(s):  
Henryk Zobel ◽  
Wojciech Karwowski ◽  
Agnieszka Golubińska ◽  
Thakaa Al-Khafaji
Keyword(s):  
Fire Resistance ◽  
Composite Beam ◽  
Structural Integrity ◽  
Bridge Structure ◽  
Long Span ◽  
Long Span Bridge ◽  
Bridge Structures ◽  
Fire Scenarios ◽  
Design Construction ◽  
Cable Stayed Bridges

<p>The problem of bridge fires is growing. Because of a bad experience in Poland, it was decided to improve fire resistance of long span bridge structures, and of cable-stayed bridges in particular. Statistics shows that fire is a real threat to this kind of structure. They also confirm that the worst results of fire are for those with an orthotropic deck rather than with a concrete one. The basic problems to solve are how to predict fire resistance of a particular bridge and how to ensure safety and structural integrity of the bridge structure. Taking into account the fact that bridge standards do not include information relating to fire protection, and fire standards do not determine rules for design, construction and maintenance of such structures, there are no regulations for this problem. Fire scenarios are devoted to buildings, but the thermo-structural behavior of bridges is different.</p>

scholarly journals Analysis and evaluation of the effect of vibrations on historical buildings

2020 ◽  
Vol 313 ◽  
pp. 00020
Author(s):  
Shota Urushadze ◽  
Miroš Pirner
Keyword(s):  
Early Detection ◽  
Dynamic Response ◽  
Human Activity ◽  
Road Traffic ◽  
Historic Buildings ◽  
Historical Buildings ◽  
Analysis And Evaluation ◽  
Vibration Magnitude ◽  
Degradation Of Materials

Continued exposure of human induced vibrations contributes to the degradation of materials and joints, causing the initiation of cracks or the growth of existing ones, such that they may endanger the structure. Loads, which an undamaged structure could safely resist, can be critical if repeated numerous times. This risk is present in various types of historical buildings, and is influenced by changes in vibration magnitude, by the distance from their source, and by the quality of the building’s maintenance. Good maintenance, which includes regular inspections, allows early detection of any emerging damage and its subsequent repair. This article describes the methods and results of the measurement of dynamic response to road traffic and other types of technical seismicity in four historic buildings. The goal of this paper is to present some examples of analysis and evaluation of the effects of such human activity.

Comparative Analysis of Frame-Core Wall Structure for Seismic Design

2012 ◽  
Vol 256-259 ◽  
pp. 2028-2033
Author(s):  
Jing Yang ◽  
Jiang Fan ◽  
Ji Xing Yuan ◽  
Qing Zhang
Keyword(s):  
Comparative Analysis ◽  
Dynamic Response ◽  
Seismic Performance ◽  
Seismic Design ◽  
Dynamic Characteristics ◽  
Wall Structure ◽  
Elastic Plastic ◽  
Linear Elastic ◽  
Plastic Phase

In this paper a skyscrapers frame-core wall structure as an example in Kun Ming, using two independent software, SATWE and ETABS, analyzed the dynamic characteristics and dynamic response of structures with earthquake in linear elastic phase and the elastic-plastic phase respectively, so that could evaluate rationality of the design of the structure as a whole and seismic performance superior or not, and it could provide an idea for audit drawing or proofread their own.

New Seismic Design Specifications of Highway Bridges in Japan

1994 ◽  
Vol 10 (2) ◽  
pp. 333-356 ◽  
Author(s):  
Kazuhiko Kawashima ◽  
Kinji Hasegawa
Keyword(s):  
Reinforced Concrete ◽  
Dynamic Response ◽  
Seismic Design ◽  
Structural Response ◽  
Highway Bridges ◽  
Lateral Force ◽  
Inertia Force ◽  
Response Analysis ◽  
Design Specifications ◽  
Recent Earthquakes

This paper presents the new seismic design specifications for highway bridges issued by the Ministry of Construction in February 1990. Revisions of the previous specifications were based on the damage characteristics of highway bridges that were developed after the recent earthquakes. The primary revised items include the seismic lateral force, evaluation of inertia force for design of substructures considering structural response, checking the bearing capacity of reinforced concrete piers for lateral load, and dynamic response analysis. Emphasis is placed on the background of the revisions introduced in the new seismic design specifications.

Comparative Evaluation of Combustion Codes for Low-Btu Gas Applications

1991 ◽  
Author(s):  
Tah-Teh Yang ◽  
Ajay K. Agrawal
Keyword(s):  
Structural Integrity ◽  
Combustion Process ◽  
Computer Code ◽  
Physical Models ◽  
Gas Combustion ◽  
Combustion Modeling ◽  
Coal Gas ◽  
Combustion Models ◽  
Efficient Combustion ◽  
User Friendly

Four computer codes (PHOENICS, PCGC, FLUENT and INTERN) representing a spectrum of existing combustion modeling capabilities were evaluated for low-Btu gas applications. In particular, the objective was to identify computer code(s) that can be used effectively for predictions of (a) the flow field to yield efficient combustion, (b) the temperature field to ensure structural integrity and (c) species concentrations to meet environmental emission standards in a gas turbine combustor operating on low-Btu coal gas. Detailed information on physical models, assumptions, limitations and operational features of various codes was obtained through a series of computational runs of increasing complexity and grouped as (a) experimental validation, (b) code comparison and (c) application to coal gas combustion. INTERN is not suitable for the present application since it has been tailored to model combustion process of premixed hydrocarbon fuels. FLUENT is easy to use and has detailed combustion models (in Version 3), however, it is not favored here because the user is unable to alter, modify or change the existing model(s). While PCGC-2 has the most comprehensive models for combustion, it is not user friendly and is inherently limited to axisymmetric geometry. PCGC-3 is expected to overcome these drawbacks. Built in combustion models in PHOENICS are similar to those in FLUENT. However, the user can implement advanced models on PHOENICS leading to a flexible and powerful combustion code.

scholarly journals The Biomechanics of Erections: Modeling the Penis as a One-Comparment Pressurized Vessel vs. Modeling it as a Two-Compartments Pressurized Vessel

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
A. Mohamed ◽  
A. Erdman ◽  
G. Timm
Keyword(s):  
Structural Integrity ◽  
Tunica Albuginea ◽  
Three Dimensional ◽  
The Body ◽  
Physical Models ◽  
Von Mises Stress ◽  
Two Dimensional ◽  
Biomechanical Models ◽  
Significant Difference ◽  
The One

Previous biomechanical models of the penis that have attempted to simulate penile erections have either been limited to two-dimensional geometry, simplified three-dimensional geometry or made inaccurate assumptions altogether. Most models designed the shaft of the penis as a one-compartment pressurized vessel fixed at one end, when in reality it is a two-compartments pressurized vessel, in which the compartments diverge as they enter the body and are fixed at two separate points. This study began by designing simplified two-dimensional and three-dimensional models of the erect penis using Finite Element Analysis (FEA) methods with varying anatomical considerations for analyzing structural stresses, axial buckling and lateral deformation. The study then validated the results by building physical models replicating the computer models. Finally a more complex and anatomically accurate model of the penis was designed and analyzed. There was a significant difference in the peak von-Mises stress distribution between the one-compartment pressurized vessel and the more anatomically correct two-compartments pressurized vessel. Furthermore, the two-compartments diverging pressurized vessel was found to have more structural integrity when subject to external lateral forces than the one-compartment pressurized vessel. This study suggests that Mother Nature has favored an anatomy of two corporal cavernosal bodies separated by a perforated septum as opposed to one corporal body, due to better structural integrity of the tunica albuginea when subject to external forces.

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