scholarly journals Effects of Surrounding Earth on Shell During the Construction of Flexible Bridge Structures

2019 ◽  
Vol 41 (2) ◽  
pp. 67-73
Author(s):  
Czesław Machelski

AbstractA characteristic feature of soil-steel structures is that, unlike in typical bridges, the backfill and the carriageway pavement with its foundation play a major role in bearing loads. In the soil-steel structure model, one can distinguish two structural subsystems: the shell made of corrugated plates and the backfill with the pavement layers. The interactions between the subsystems are modelled as interfacial interactions, that is, forces normal and tangent to the surface of the shell. This is a static condition of the consistency of mutual interactions between the surrounding earth and the shell, considering that slip can arise at the interface between the subsystems. This paper presents an algorithm for determining the internal forces in the shell on the basis of the unit strains in the corrugated plates, and subsequently, the interfacial interactions. The effects of loads arising during the construction of a soil-steel bridge when, for example, construction machines drive over the structure, are taken into account in the analysis of the internal forces in the shell and in the surrounding earth. During construction, the forces in the shell are usually many times greater than the ones generated by service loads. Thus, the analytical results presented in this paper provide the basis for predicting the behaviour of the soil medium under operational loads.

Author(s):  
Damian Beben

The paper characterizes the problem of preservation of wildlife animals in connection with extension of transportation road systems. The constantly evolving transportation infrastructure in Europe, especially in its Midwestern part, on one hand connects, making it easier for people to travel and ship goods, but on the other hand it irreversibly divides and leaves a painful impress on virgin natural areas (fragmentation of the environment). The paper briefly presents the European Ecological Network Nature 2000 as the European Union program concerning the environmental protection. It enumerates possible types of animal crossings together with their characteristics. Some examples of underpasses, overpasses and crossings on the road surface are also presented. It also presents specificity and phases of designing engineering structures of this type, as well as the most common design errors and their influence over the use of such structures by animals. Finally the soil-steel bridge structures made from corrugated plates are characterized in their function as crossings for animals. The conclusion mentions complexity of the problem of animal crossing construction, which can be of use to designers and constructors of this type of engineering structures. Santrauka Straipsnyje apžvelgtos laukinės gyvūnijos išsaugojimo problemos, susijusios su besiplečiančiu transporto tinklu. Nuolat besivystanti transporto infrastruktūra Europoje, ypač Vidurio vakaruose, viena vertus, jungia ir palengvina žmonių mobilumą,sukuria jungtį su uostais, tačiau, kita vertus, daro didelę žalą natūraliai aplinkai (aplinkos fragmentacija). Straipsnyje trumpai pristatoma Europos ekologinio tinklo ,,Natura 2000“ ES programa, skirta aplinkos apsaugai. Išvardyti galimi gyvūnų perėjų tipai su jiems būdingomis charakteristikomis. Pateikiami požeminių, virš kelio ir perėjų per patį kelią pavyzdžiai. Straipsnyje taip pat apžvelgiama inžinerinių struktūrų projektavimo specifika ir fazės, aptariamos dažniausiai pasitaikančios projektavimo klaidos ir jų įtaka gyvūnams. Galiausiai apibūdinamas dirvos ir plieninių tiltų struktūros, pagamintos iš gofruotų plokštelių, naudojimas gyvūnų perėjoms. Išvadose aptariamas gyvūnų perėjų konstrukcijų problemų kompleksiškumas, į kurį turėtų atkreipti dėmesį gyvūnų perėjas konstruojantys inžinieriai ir dizaineriai. Резюме Анализируются проблемы охраны диких животных в связи с расширяющейся транспортной сетью. Постоянно развивающаяся транспортная инфраструктура в Европе, особенно на западе центральной части Европы, с одной стороны, объединяет людей, облегчает их мобильность, открывает доступ к портам, с другой – наносит непоправимый вред натуральной природе. В статье вкратце представлена программа Европейской экологической сети – Natura 2000, касающаяся охраны окружающей среды. Перечислены возможные типы переходов для животных с их типичными характеристиками. Представлены примеры подземных переходов, переходов над дорогой и по самой дороге. Проанализирована специфика и фазы проектирования инженерных структур, а также часто совершаемых ошибок при проектировании и их влияние на животных. Охарактеризовано применение для переходов животных почвенностальных структур мостов из гофрированных пластин. Проанализирована комплексность проблем, касающихся конструкций для переходов животных, на которые следует обратить внимание инженерам и дизайнерам при констру ировании переходов для животных.


Author(s):  
A. I. Garipov ◽  
◽  
P. A. Pyatkin ◽  

The article presents a technique of calculating steel structures connections taking into consideration the results of seismic analysis of steel structure carried out by linear spectral method. This technique allows reaching the equilibrium of forces and moments applied to the connection, wherein extreme internal forces’ values received correspond to the internal forces’ values obtained according to the currently valid acting construction codes.


2013 ◽  
Vol 838-841 ◽  
pp. 1556-1561
Author(s):  
Na Xie ◽  
Gan Wang ◽  
Jian Zhong Zhao ◽  
Zhi Ming Zhao ◽  
Hui Xin Zhou ◽  
...  

In rare strong earthquakes, the steel structure may occur the nonlinear behavior and redistribution of internal forces. In order to understand the post-buckling behavior of steel structures and determine the weak areas of the structure, and then determine whether the structure under strong earthquakes meets the seismic design goal or not, this paper adopts the FNA method to analyze the response of large profiled steel structure under severe earthquakes. Finally, we draw some general conclusions which are valuable for designing the large profiled structure.


2013 ◽  
Vol 438-439 ◽  
pp. 530-534
Author(s):  
Lan Yao ◽  
Yu Min Liu ◽  
Yong Zhi Zou ◽  
Qiao Zhi Lu

After fire, the strength of steel materials and stiffness of artifacts decrease significantly, which cause the redistribution of internal forces and increase the difficulty in testing of materials, identification and evaluation of steel structures after fire. This paper mainly discusses the identification and evaluation of steel structure of one project undertaken a fire by empirical test. It is speculated that the temperature of the fire was more than 850°C, area covered includes 1~4/Q~W axis and 5~6/H~W axis of the factory, after the fire in the safety appraisal building assessment, it is categorized as class C which influences the safety of the whole structure. From the results of this appraisal, suggestions are made which could be regarded as a guide in similar engineering projects in the future.


1981 ◽  
Vol 8 (4) ◽  
pp. 519-534 ◽  
Author(s):  
C. Mirza ◽  
W. A. Porter

Soil–steel structures is the name given to bridge, culvert, and underpass types of conduit openings designed with corrugated steel pipe plates (SPCSP) and engineered soil around these plates. The maximum span for these structures has approached 16 m in an arch configuration. Their design was rationalized by Canadian research in the 1960s, concurrently with the construction of several hundred units. Recent codification of design requirements has drawn attention to the need for documenting construction practices and other lesser known physical aspects of these structures. This paper is a contribution towards that documentation.


Author(s):  
Robert Cichocki ◽  
Ian Moore ◽  
Kevin Williams

Buried steel structures, commonly referred to as buried bridges, culverts, or soil-steel structures are a valuable bridge crossing solution. Owners manage their bridge assets by evaluating their condition and rehabilitating as required. Ontario’s resources for managing and rehabilitating buried steel bridge structures are limited, and an investigation into the maintenance and rehabilitation practice of Ontario’s assets demonstrates a lag in their maintenance and rehabilitation. Knowledge regarding rehabilitation of these structures is dispersed and unconcise, leaving owners challenged to understanding how to best manage and rehabilitate their assets. This paper investigates the age, condition, and rehabilitation of steel buried bridges in Ontario and reviews the commonly encountered deterioration and distress mechanisms along with the state-of-the-art rehabilitation practices. With an understanding of structural behavior, deterioration, and rehabilitation opportunities for structures nearing the end of their service lives, owners will be better equipped to effectively manage their inventory and leverage the economic, social, and environmental value of buried structures.


2016 ◽  
Vol 710 ◽  
pp. 451-457 ◽  
Author(s):  
Scott Walbridge ◽  
Denis Beaulieu ◽  
Federico M. Mazzolani

In 2011, a new chapter was added to the Canadian Highway Bridge Design Code (CAN/CSA S6) [1] enabling the design of aluminum bridge components and structures in Canada. In 2016, activities are well underway, which will result in significant modifications to the Canadian aluminum structures code: “Strength Design in Aluminum” (CAN/CSA S157) [2] and the Canadian code for welding of aluminum structures: “Welded Aluminum Construction” (CAN/CSA W59.2) [3]. This paper discusses the philosophies employed in the development and modernization of these design codes and highlights some of the major changes to these codes. In the case of CAN/CSA S6, the new aluminum chapter was basically written from scratch. However, a practical approach was employed of using material from existing codes, where appropriate (including CAN/CSA S157, the AASHTO Bridge Design Specification [4], the U.S. Aluminum Design Manual [5], and the Eurocode [6]), and organizing the chapter to resemble as closely as possible the chapter for steel bridge structures, so that designers would be relatively comfortable with the new material. In the case of CAN/CSA S157, a significant reorganization of the code contents will be occurring in the latest edition, in order to bring it closer to the Canadian steel structures code (CAN/CSA S16) [7] where possible, again to make the code more user friendly. In the case of the aluminum welding code (CAN/CSA W59.2), changes are being considered to allow the use of technologies such as friction stir welding (FSW) and post-weld treatments (e.g. peening, grinding) for improving fatigue performance. This work is being done with input from Canadian industry experts and academics, in consultation with international experts from the U.S. and Europe. It is expected that this work will lead to substantially improved design codes, resulting in significant benefits in terms of the economics and safety implications of designing aluminum structures in Canada.


2011 ◽  
Vol 255-260 ◽  
pp. 2341-2344
Author(s):  
Mohammad Saeed Masoomi ◽  
Siti Aminah Osman ◽  
Ali Jahanshahi

This paper presents the performance of base-isolated steel structures under the seismic load. The main goals of this study are to evaluate the effectiveness of base isolation systems for steel structures against earthquake loads; to verify the modal analysis of steel frame compared with the hand calculation results; and development of a simulating method for base-isolated structure’s responses. Two models were considered in this study, one a steel structure with base-isolated and the other without base-isolated system. The nonlinear time-history analysis of both structures under El Centro 1940 seismic ground motion was used based on finite element method through SAP2000. The mentioned frames were analyzed by Eigenvalue method for linear analysis and Ritz-vector method for nonlinear analysis. Simulation results were presented as time-acceleration graphs for each story, period and frequency of both structures for the first three modes.


2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Renda Zhao ◽  
Yuan Yuan ◽  
Xing Wei ◽  
Ruili Shen ◽  
Kaifeng Zheng ◽  
...  

AbstractBridge construction is one of the cores of traffic infrastructure construction. To better develop relevant bridge science, this paper introduces the main research progress in China and abroad in 2019 from 13 aspects, including concrete bridges and the high-performance materials, the latest research on steel-concrete composite girders, advances in box girder and cable-supported bridge analysis theories, advance in steel bridges, the theory of bridge evaluation and reinforcement, bridge model tests and new testing techniques, steel bridge fatigue, wind resistance of bridges, vehicle-bridge interactions, progress in seismic design of bridges, bridge hydrodynamics, bridge informatization and intelligent bridge and prefabricated concrete bridge structures.


Author(s):  
Haigen Cheng ◽  
Cong Hu ◽  
Yong Jiang

AbstractThe steel structure under the action of alternating load for a long time is prone to fatigue failure and affects the safety of the engineering structure. For steel structures in complex environments such as corrosive media and fires, the remaining fatigue life is more difficult to predict theoretically. To this end, the article carried out fatigue tests on Q420qD high-performance steel cross joints under three different working conditions, established a 95% survival rate $$S{ - }N$$ S - N curves, and analyzed the effects of corrosive media and high fire temperatures on its fatigue performance. And refer to the current specifications to evaluate its fatigue performance. The results show that the fatigue performance of the cross joint connection is reduced under the influence of corrosive medium, and the fatigue performance of the cross joint connection is improved under the high temperature of fire. When the number of cycles is more than 200,000 times, the design curves of EN code, GBJ code, and GB code can better predict the fatigue life of cross joints without treatment, only corrosion treatment, and corrosion and fire treatment, and all have sufficient safety reserve.


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