In order to achieve accelerated and less expensive construction for arch bridges, optimized steel composite sections with variations of material and dimensions were proposed for the arch ribs. The proposed arch rib is made of fabricated steel tubular section with concrete fill or reinforced concrete topping based on stress distribution. An important advantage of this composite section is that a base arch frame of steel tubular section can be erected vertically and rotated to closure in limited workspace and within a short period. A particular composite with hollow steel box and reinforced concrete topping is used for combined compression and positive bending in the mid-span region, which is quarter-spans from the crown, to reduce the self-weight and cost. An in-depth understanding of the load carrying characteristics theoretically and experimentally can be very crucial for the design optimization. The objective of this research is to study experimentally the behavior, failure mechanism and performance of this composite section. The test includes the simulation of pure bending with lateral load, and pure compression with central axial loading as well as combined compression and bending with eccentric axial loading. This paper presents the experimental results of a series of test specimen tested under different load conditions. The results demonstrated that the proposed composite section can meet both strength needs and performance requirements. The composite section achieved its ultimate design strength with fully developed concrete compressive strength and steel tensile strength, without premature failures such as crushing or cracking of concrete or buckling of steel.
The search for new architectural shapes may lead to schemes of bridges which cannot be traced back to known and tested typologies. In these cases, a new aesthetics requires new static views. The novelty of the De Gasperi Bridge, located in Milan, consists of two steel arches diverging towards the lateral sides of the deck. Such a choice involved particular structural problems as regards to both the vertical loads and the lateral ones due to wind and earthquake. Another delicate issue was posed by the array of joints connecting the tubular hangers and the arches, for which cardan joints have been employed in order to avoid any flexural stresses. The paper illustrates the criteria which led to the conception of a structural system which, while respecting the shape determined by architectural choices, activates an effective and natural force path. A synthesis of the analyses and of the experimental tests performed on the cardan joint are presented.
The paper covers the seismic evaluation and upgrading of an existing 20 - storey hotel building for compliance with a peak ground acceleration of 0.4g in the city of Istanbul. The assignment was performed by SECO. It was finalised only recently and lasted for about 6 years. The implementation of the strengthening design into an operating hotel proved to be an exciting challenge. The standard storey area of the building is about 35.000 m2. The building's structure comprises an (in plan view) S-shaped classical reinforced concrete frame of beams, columns and slabs, divided by 2 joints in 3 independent blocks, but disturbed by the presence of some major irregularities. Quite an experience …
The Adapazari City Hall was at a closest distance of 11 km to rupture of the July 22, 1967 Akyazi earthquake (Mw 7.0). The building with five-story R/C frame system was heavily damaged and retrofitted through conventional methods in an eight-month period after the earthquake (The retrofit project and application were carried out by the authors). After 32 years later, the retrofitted building suffered a strong earthquake (Mw 7.4) on August 17, 1999. The closest distance to the rupture of Adapazari was only 3.1 km (PGA 0.4g). Following the main shock, it also suffered a moderate aftershock (Mw 5.7) with PGA 0.35g and a strong main shock (Mw 7.2). These earthquakes caused collapse and heavy damages at many buildings in Adapazari. The Adapazari City Hall during these earthquakes experienced no structural damage and it was utilized as the city crisis centre. The lateral rigidity of the building after 1967 earthquake was provided by new shear walls instead of existing non-ductile structural elements. Retrofitted columns, new rigid beams, new structural masonry walls, repaired slabs and beams contributed the enhanced remarkable performance as well. Seismicity and geology of Adapazari and the seismic response of the building are discussed.
A brief description of the 1755 Lisbon earthquake is made in what regards the multiple aspects of scientific and technological background. These descriptions are oriented towards a better characterization of the seismic source, the wave propagation, and also to the causes behind the observations in nature, in the housing and population. The interpretation of the various phenomena is supported by the structural behaviour of simple objects and structures for which it was possible to partially recover the seismic input acting at the foundation level, leading to a more comprehensive understanding of the entire phenomenon. The analysis of the tsunami, of several monumental structures especially the Águas Livres Aqueduct, the damage inflicted to different types of buildings, etc., constitutes the essential basis to mount the large and intriguing puzzle that the 1755 earthquake still is. Though science has already given many important clues, there are yet a large number of questions to be answered which will contribute to a full comprehension of the phenomenon and in the definition of future hazards.
This note focuses on a specific aspect of the structural modelling of the Paderno d'Adda Bridge, a marvellous Italian historic wrought iron bridge with riveted connections that was completed in 1889 and opened to both railway and road traffics [1-2]. Within the current attempt
of building a full 3D FEM model of the structure [3-7], the metallic piers of the bridge are considered [5-6], specifically the pier on the arch. The morphology of the piers has been reconstructed from the inspection of the original design drawings and implemented into a FEM model.
Then, a structural analysis has been performed in the elastic range, by considering loading distributions that were conceived at design stage and also conditions that are nearer to present-state railway standards.
The huge r.c. enlargement (1933-1939) of the Shrine of Pompeii in Italy is described in this paper as a case history of structural and historical interest. To preserve the features of the old masonry church, built around the Icon of the Blessed Virgin of the Rosary, the enlargement
had necessarily to be three-dimensional (i.e. both in plan and elevation), to guarantee to everybody the same perspective look toward the main altar. This was extraordinary challenging for that time, when reinforced concrete was at the beginning of his history. Indeed, the structural designer
conceived a sort of cage enveloping (even at foundation level) the old masonry structure (one nave, 420 m2, 18 m high) with a new one (three aisles, 2000 m2, 45 m high). Although the new r.c. structure was masked for the elements inside the church, bare r.c. elements
can be found between the old vault and the new roof, and this could be useful to start a structural health monitoring.
The redevelopment of a city road network from a logistic and technological point of view often means to clash with huge economic and financial interests and to disappoint citizens' expectations. C (capital city of North Rhine-Westfalia region - Germany) is the emblematic case of an unresolved conflict that was brought about in 1961-62 with the construction of the elevated road called “Tausendfüssler (the millipede).The difficult relationship between this structure, its complex functional requisites and the traditional image of the city has now led to the decision to demolish the road. As a result, one of the most significative examples of post-war German engineering is bound to disappear.
The paper describes the recent development of an Australian standard (AS/NZS4673)  for the design of cold-formed stainless steel structures. The standard is based on the American (ANSI/ASCE-8) Specification for the Design of Cold-formed Stainless Steel Structural Members  but augmented to provide rules for cold-formed hollow section members and welded connections. Explicit design rules for the flexural buckling of compression members are also implemented. Further, mechanical properties are included for weldable chromium steels and austenitic-ferritic (duplex) alloys, which are in addition to the alloys included in the ANSI/ASCE-8 Specification. Welds are required to comply with AS/NZS1554.6  or the ANSI/AWS D1.3 Specification . The paper summarises the scope and additional design rules of the new Australian Standard.
This paper is meant to deliver an overview on the damages and the following repairs of the structures of the 26th and 27th floor due to the plane accident occurred on April, the 18th 2002.An aircraft Commander 112 TC Commander impacted the facade of the Pirelli skyscraper getting into the building, where its gasoline tanks exploded.This paper is divided into two parts. The first one focuses on a simplified analysis, of the witnessed structural damages, making some necessary assumptions on the dynamic of the accident.In the second one, the realigning process is presented.
The existing open air aquatic complex on Sainte-Hélène Island in Montréal was chosen to host 2005 Aquatic Sports World Championships. The old concrete pools built in 1953 had to be replaced by new structures and the new pools and bleachers had to fit in the existing site. In the new layout, the swimming pool was relocated which led to some problems due to soil conditions. The soil was sensitive and heterogeneous therefore differential settlements and resulting lateral displacements had to be considered in the design in order to respect the strict dimensional criteria for Olympic pools. To guarantee the quality of works within a very tight schedule, the upper section of the walls was made of prefabricated steel panels. As a result, the rigid continuous “box originally formed by the concrete corridor around the pool was lost. Consequently, a combination of soil consolidation, interaction of soil-structure and phasing of construction-backfilling became part of design.
The development of Beijing 2008 Olympic venues is a vast and complex program where enormous risks embedded. A risk assessment model is developed to meet the requirement of the BOCOG to report to the IOC the overall construction risk level of each venue every three months. A ratings method of the AHP is adopted to establish the model in accordance with Olympic venue construction objectives. The development of the model consists of three steps: a) an evaluation hierarchy is firstly set up based on literature review, interviews and discussions with experts; b) an ordinal scale of five levels is adopted to design measures for the lowest-level attributes of the hierarchy through rounds of in-depth interviews and discussions with experts; and then c) weights of attributes are determined through a workshop and interviews. Finally, the model is tested using two Olympic venue projects under construction and the result shows that the model is valid and practical.
p>On June 08, 2008 at 15:25 a strong earthquake with moment magnitude Mw=6,5, named “Achaia- Ilia” occurred in Greece. The focal depth was estimated to be around 30km and the epicentre was located at a distance 36 km SW from the Rion-Antirion Bridge.
The Rion-Antirion Bridge, a five-span cable-stay bridge (286m + 560m + 560m + 560m + 286m), has been designed to withstand earthquakes with P.G.A. of 0,48g and tectonic movements up to 2m between consecutive pylons. In order to satisfy the above requirements the deck superstructure was made continuous for the full length of 2252m and fully suspended from the four pylons.
An innovative energy dissipation system, designed by Vinci and developed by FIP Industriale, connects the deck to the pylons and limits the lateral movement of the deck during an earthquake, while dissipating the seismic energy with huge – never built before - viscous dampers. The bridge is also equipped with a complete monitoring system capable of collecting high frequency data at critical parts of the structure during a seismic or wind dynamic event.
The paper presents evidences of the good performance of the dissipation system during the above mentioned earthquake. From the analysis of the monitoring data collected during the event and the thorough inspections performed after, it was confirmed that the behaviour of the bridge was in accordance with the analytical predictions and well within the serviceability limit states.</p
The core of Stuttgart 21 is the new underground station with its characteristic “light eyes. The railway tracks are rotated against the existing terminal station by an angle of 90 degrees, which means they will be oriented transversely across the Stuttgart valley. This underground station is designed as a reinforced concrete shell structure, in such a way that the concrete shell is always in compression. Its “green cover forms the link to a new municipal district on the location of the current platform area. This paper describes the development of the shape of the shell structure, from a first soap membrane model over suspended chain models and digital CAD models to discrete finite element analysis models. The creation and modelling of the system, as well as the special calculations required are explained in some detail.
Steel bridge engineering in Australia is undergoing significant advances. BHP Steel has led research and developments to make steel bridges a superior long term investment through lower initial and life cycle costs. Overall reduction in costs has been achieved through advances in surface protection specifications, design aids, powerful bridge design software and advanced construction methods.The introduction of the `super-heavy' SM1600 design live loading, reputedly the heaviest loading used anywhere in the world, has brought new challenges for bridge designers. This and an unprecedented emphasis on safety and environmental impact has created new design paradigms, such as the use of pier redundancy and longer spans to bridge over environmentally sensitive areas.This paper features steel bridges displaying the recent advances, and outlines concepts for medium span bridging solutions for the 21st century. These include pier redundant safe and virtually indestructible bridges, systems allowing progressively upgradeable strength and low maintenance coatings.
Nowadays when structures are defined by their unique forms, innovative use of materials, contextsensitive integrity that create dramatic points, they are acknowledged to be world-class designs. It is very difficult to design bridge structures that offer so manifold rewards, which demands a new set of design environment in which multi-disciplinary experts collaborate each other. Above all the issues to address to develop new design environment, a strategic coordination among architects and engineers might play a key role to elevate modern bridge design to an artistic level. This paper has focused on how the common platform is being evolved for a true collaboration for architects and engineers toward new design paradigm for 21st century bridge design. In association with the collaboration work, a new Silkworm pedestrian bridge was studied as a representative case that was completed through a strong collaboration between artists and engineers as well as community agent. A collaborative design process was developed based on this study. It is expected that architects and engineers can get together through the proposed design platform from conception to completion to create a powerful and efficient structural system and form as well.
The 20th century can be characterized as the century of transportation technology. Early 20th century brought on the popularity of automobiles, and with increase in mobility, demand for more roads and bridges became evident. With this demand, and with the development of new construction materials, wood, that was the predominant material for building bridges in the 19th century, was soon replaced by steel and concrete in the 20th century. The use of steel and concrete as the material of choice increased even more with the signing of the Federal Aid Highway Act of 1956 that started the building of the US Interstate Highway System. However, even with all the increased use of steel and concrete, wooden bridges continued to be built on secondary and low-volume roadways as many still considered it an attractive material for short-span structures. Today there are approximately 40,000 timber highway bridges on public roadways in the United States (US) with span lengths greater than 6.1 m. In addition there are approximately 40,000 steel stringer bridges with timber decks. This paper presents a historical perspective on the use of timber bridges in the United States, briefly describing the various design types. It further summarizes the national timber bridge programs that are leading the way to new developments in timber bridge technology for the 21st Century.
The Gautrain Rapid Rail Link is a state-of-the-art rapid rail network currently under construction in Gauteng, South Africa. Viaduct V5c is a 3,2km long segmental construction and is mostly founded in material overlying dolomite bedrock.
The route for viaduct V5c is generally underlain by dolomitic ground with occasional syenite intrusions. The area is well known for the risk of sinkhole and doline formation due to the erodibility of the in situ soil. Sinkholes inherently pose a risk to the rail service and (if left untreated) may potentially have catastrophic consequences.
This paper will reflect on the considerations behind the choice of structural type and associated construction method. The paper will focus on the key aspects pertaining to the final geotechnical solutions & structural design, associated with viaduct V5c.
This paper presents, based on a new discrete model analysis, the elasto-plastic behaviors and the load-carrying capacity of portal frame tower with a height of 350 meters in a 3000-meter super long-span suspension bridge. Furthermore, the ultimate strength of an independent tower model obtained from the new discrete analysis is compared with that obtained from elasto-plastic fnite displacement analysis applied to the suspension bridge model. For the out-of plane ultimate strength of the tower, we confirmed that the new discrete model analysis has a good precision through comparison with the results obtained from the elasto-plastic fnite displacement analysis, and that the required bending rigidity of the tower can be designed in the negative region of F values from this study.
One of the first privately financed projects in Germany was the national road B 31 East between Freiburg and Kirchzarten. This infrastructure project not only helps realize an efficient traffic concept but permits a further development of the infrastructure of the city of Freiburg as well.As a direct result of the project, the overground East-West traffic is drastically reduced. This is achieved by directing the main traffic underground. Two double-cell tunnels (850 m and 1230 m) and two noise insulation galleries (275 m and 640 m) were planned. These have been built in the inner city part of the project. The outer city part of the infrastructure project consists of five bridges including a number of noise insulation walls.The tunnels have been constructed using both the `cover and cut' as well as the `cut and cover' method. High security standards have been applied including a very sophisticated traffic control system.These aspects, which are of importance in densely populated areas, are outlined in the paper.
Again limits have been pushed further with the realization of the key element of the extension of the Condamine port at Monaco, a 352 m long and 163 000 tons semi-floating pier.The highly pre-stressed reinforcement concrete structure with a design life of 100 years is attached to the main land abutment with a very complex and 770 tons steel ball-joint system while the other end of the pier it is secured with two sets of fixed anchor chains to the seabed.This exceptional project is a mix of building techniques, mechanical engineering, and offshore works: it includes several world records and, particularly, the spectacular connection of the ball joint system.All these design breaking records are possible thanks to the evolutions in civil design & construction methods. In this context another evolution is of great help to allow confirming that the structures are behaving like expected by the calculation models: the monitoring tools. New technologies for the monitoring of structures are powerful tools to better understand the behaviour and make sure that structure remains in good health over time.In this paper we will review the structural health monitoring system that is installed for this extraordinary structure.
This paper presents a simplified macro-mechanical models for both brick-mortar and brick-FRP interface in masonry wall. Model equations for Finite Element Analysis are chosen in such a way that only primary variable in those equations is the internal strain that comes from the incremental strain as input parameter during the loading steps of FEA. The interface is proposed as a zero thickness plane element where the brick unit itself is of 20-nodes solid element and FRP as 8-nodes shell element. The model equations were derived from phenomenological concept of load-reaction for masonry shear wall that can fully capture both the pre-peak and post-peak behavior of masonry wall. Model equations were carefully formulated for loading, unloading and reloading that can be experienced during the loading process. Modern concept of Elasto-Plastic and Fracture(EPF) model for non-linear plasticity is implemented in those equations for work-hardening behavior of the constituent materials and interface, where as the softening process itself was translated through non-linear equations that conform some of the experimental stress-strain curve. Finally the results from the analysis are compared with the experimental data that are available on some authentic literatures and they show good agreements. Some discrepancies were observed due to absence of sufficient experimental clarity. After successful completion of the analytical part of this study, a comprehensive experimental work of our own will be followed.
A recent topic, BIM could be considered as an effort to integrate all the information. So far, the integration of cost and schedule data has been done successfully as there is a good case of EVMS in order to synthesize those data. There have been many efforts to develop a 5D system that integrates cost, schedule data and a 3D model, but its technology is so difficult that few have succeeded. The 5D system will have many advantages once it is made: The visualization of schedule data and verification of cost in real time are possible and the future cost and schedule can be expected accurately. Especially, in case of an atypical structure the clash of members and errors of drawings which are hard to find in 2D drawings can be detected and corrected in a 3D model. This paper presents the methodology and results to develop a 5D system with the integrated cost and schedule data from EVMS, and a 3D model of the 2nd Geumgang Bridge within nD-CCIR, a 5D system developed in the UK.
Design of a high-speed railway line requires collaboration of heterogeneous application systems and of engineers with different background. Even there are many automated systems for individual work processes, a document-based work system has lots of information loss between processes. Object-based 3D models with metadata can be a shared information models for the effective collaborative design. Well-organized data for the railway lines are also essential for the effective maintenance. In this paper, railway infrastructure information model is proposed to enable integrated and inter-operable works throughout the lifecycle of the railway infrastructures, from planning to maintenance. This research is a part of the development of Virtual Construction System which is sponsored by Korea Ministry of Construction and Transportation. In order to develop the model, object-based 3-D models were built for a 10km railway among Korea High-speed Railway lines. The model has basically three information layers for designers, contractors and an owner, respectively. The railway lines mainly consist of bridges and tunnels. Prestressed concrete box-girders are the most common superstructure. The design information layer has metadata on requirements, design codes, geometry, analysis and so on. The construction layer has data on drawings, real data for material and products, schedules and so on. The maintenance layer for the owner has the final geometry, material data, products and their suppliers and so on. These information has its own data architecture which is derived from similar concept of product breakdown structure(PBS) and work breakdown structure(WBS). The constructed RIIM for the infrastructures of the high-speed railway was successfully applied to various areas such as design check, structural analysis, automated estimation, construction simulation, virtual viewing, and digital mock-up. The integrated information model can realize virtual construction system for railway lines and dramatically increase the productivity of the whole engineering process.
This analytical study was programmed to predict the dynamic response of a full scale reinforced concrete (RC) bridge pier model in shaking table test. The results of dynamic finite element analysis (FE analysis) using `FINAL' well agreed with the results of the test about the dynamic response and the failure time of the model with rebar cut-off sections. The data about bond slip of longitudinal bar and strain of hoop were insufficient to predict the brittle failure time of the pier quantitatively. In this study, it was obtained that the criterion focusing on the increment of softening concrete element number is useful to predict the brittle failure time.
KUBA is a comprehensive road structure management system, developed for the Swiss Federal Roads Authority. It is similar to other state of the art systems such as Pontis, Danbro, the Ontario Bridge Management System, etc. but has numerous distinctive characteristics. KUBA consists of two principal components, a data collection system (KUBA-DB), and a management system (KUBA-MS) and two additional components, a special transport assessment system (KUBA-ST) and a reporting system (KUBA-RP). The focus of this paper is set on the two principal components KUBA-DB and KUBA-MS.
This article gives an overview of the important aspects of KUBA version 4.0, including a discussion of the impact of KUBA on the planning process of the Swiss Federal Roads Authority, namely on 1) the evaluation of financial needs, 2) the general management of structures, including the formulation of inspection and intervention policy, 3) the inspection of structures, and 4) the planning of interventions.
It also addresses the model used in KUBA to determine maintenance policy, which minimise the long term costs.
This paper presents the current development state and initial findings of a joint research program of the Swiss Federal Railway Corporation (SBB) and the Institute for 4D Technologies UAS Northwestern Switzerland (i4Ds). The scope of the project is to determine, how 3D/4D modeling, simulation and visualization of products (artifacts), processes and organisations can support lean construction. The SBB plans to implement lean construction methods on their face-lifting and reshaping program of 400 regional railway stations with the aim to improve the quality and the reliability of the processes and to achieve considerable cost reductions .
A major failure of the three-span State Route (SR) 69 Bridge occurred during construction when the two erected spans of the steel superstructure suddenly collapsed and fell into the Tennessee River. An investigation was undertaken to determine the cause of the failure. Structural analyses were conducted to assess the stability of the partially-erected bridge superstructure at the time of collapse. The results of these analyses were compared to physical evidence observed during the field work. The investigation showed that the collapse of the SR 69 bridge resulted from a lateral instability in one of the three primary plate girders. The instability was precipitated by the removal of a critical cross frame that had been partially installed for bracing purposes.
One of the most destructive earthquakes in India occurred in 2001 in the Kachchh region of the western Indian state of Gujarat with intensity of 7.7 on Richter scale. Extensive damage to existing buildings occurred with large numbers of human deaths. Subsequently, the authorities have taken up projects involving retrofitting of large nos of buildings which survived the earthquake but with structural damage. The paper highlights the types of buildings, method adopted for seismic evaluation, retrofit strategy, field investigations including RVS, Non Destructive Testing and digitization of the 1184 nos buildings features on a GIS map for future ready reference.
The Shanghai Yangtze Bridge, located over open water at the entrance of the Yangtze River, is currently under construction. A cable-stayed bridge solution with the main span of 730m is adopted to meet the navigational demands of the main channel. The bridge comprises the dual-direction 6-lane expressway and 2-lane traffic railways. In fact, the 730m cable-stayed bridge over the main channel is the longest-spanning bridge of its kind for combined highway and railway traffic. The technical standard is studied to ensure the safety of railway and comfortableness of passengers for the combined highway and railway on the same plane. As the symbolic structure at the mouth of the Yangtze River, it also needs to take the aesthetics into consideration greatly. This paper presents the design and technical characteristics of the main channel cable-stayed bridge.
Among highway systems, bridge is the most vulnerable component to the earthquake hazard, so the bridge seismic design is considered to be an important part of the bridge design. On may 12, 2008, a Ms.8.0 earthquake occurred in Wenchuan China, which was the one of biggest earthquake China has suffered from 1950s. In this big earthquake, with different distance from the epicenter, a great deal of bridges suffered varying degrees of damage, i.e. bridge collapse completely, girders fall down, bearing damage, and so on. According to analyze these phenomena of damage, more in-depth understanding of the bridge performance in the actual of the earthquake will be got. This paper introduces and analyzes the representative damage of bridges during the earthquake. In the end, some of the recommendations will be given to improve the bridge seismic design.
A 9.5 km long elevated expressway with four lane deck has been taken up in Bangalore, India. The project is presently the longest such structure in India and has been conceived with large scale precast segmental construction with glued matchcast segments and bonded post-tensioning cables. The paper highlights the background of the concept development, the extent of precast prefabrication work involved, structural arrangement, precasting methods for the segments, launching scheme of superstructure and erection scheme for the multilevel interchange. The project involves construction of large numbers of bored cast-in-situ piles using high speed rotary hydraulic rig operating in one of the busiest corridors of the city.
This paper describes the replacement and upgrading of railroad bridges in the US, through specific “change-outs case examples, identifying the different factors which make them the keystone of railroad bridge maintenance, repair and replacement nowadays. It also covers advancements in the railroad industry related to railroad bridge upgrades which minimize railroad traffic interruptions. Finally, it identifies potential areas of development and expansion from these lessons learned on railroad engineering which might be useful for other structural engineers involved with infrastructure design, construction and maintenance.
To optimize road access to the Port of Zeebrugge the Ax-project was set up: a new highway A11 will be built connecting the harbour to the E40 and E34 motorway. As the port is adjacent to one of the oldest and purest polders of Flanders, environmental impact is to be considered carefully. Part of the landscape and buildings are protected heritage, or protected habitat areas for avifauna. The A11 will cross railways, a navigation channel, secondary roads, pipelines of national importance and fragile hydraulic systems. Two Interchanges and one exit/entrance complex in the harbour are to be built. Several “feasible alternatives with bridges and or tunnels were tested. A methodology was established to rank alternatives. Using an integrated design approach a solution was found in designing a partly subterranean highway. The design includes more then 60 civil engineering structures. Among them a movable bridge, two approach viaducts, and tunnels.
The HSL (the Hogesnelheidslijn-Zuid, or High-Speed Line South) is being integrated into its environment with great care. The flatness of the Dutch countryside means that integration brings a great many problems. Careful alignment, design and layout make it possible to preserve landscape features, avoid/limit/compensate for negative effects and, in some cases, create benefits that did not exist before. All this requires discussion at an early stage between the parties involved. The present paper shows how integration targets were achieved, taking as an example the section of line that shares an alignment with the A16 motorway in the province of Noord-Brabant.
A daily traffic of app. 160,000 vehicles and 140 trains crossing the Ponte 25 de Abril makes it one of the busiest routes in Europe. This landmark has to bear enormous loads especially caused by the trains crossing it since 1999 after finishing the renovation and the completion of additional road lanes and the rail deck on this structure originally build in 1966. With each train an accumulated movement of up to 200 mm at a maximum speed of 15 mm/s can be noticed at the bearings supporting the bridge deck at the abutments and the piers. Only extensive maintenance prevented a total failure of the original roller bearings until these were exchanged by modern sliding bearings in 2004. Still an accumulated sliding path between 2,132 and 3,703 m per year on velocities 8 times higher than expected for regular sliding bearings made the use of new materials necessary. A permanent monitoring of the longitudinal movements of all 8 bearings allows the verification of the capabilities of these new materials in real service, which has been widely simulated in laboratory tests before. A robust measurement, data logging and communication system ensures the recording of the accumulated sliding path without interruption. Additional logging of detailed movement data in combination with recorded environmental information allows an analysis of the structural behaviour regarding its longitudinal movement. The paper will introduce the new sliding materials as well as the used monitoring system. The analysis of more than 2 years of movement data shows useful information not only for the bridge bearings itself, but about the overall behaviour of this remarkable suspension bridge. The special advantages of such continuous long-term monitoring will be presented. Prospects for possible extensions of the existing system will be given.
Noise and vibration emit when a large lorry passes the expansion joints on road bridges, causing serious environmental problems. Field measurements were conducted on the road bridge, showing that the dominant frequency was 13.3Hz when vehicles ran over the joints. A new type of damper, the impact absorbing damper based on momentum exchanging mechanism, has been proposed to suppress the vibration occurred at the expansion joints. This damper system consists of the contact device between the RC slab and the additional mass with springs and oil dampers. When the vehicle wheel hits the expansion joints, the impact force is directly transferred to the attached mass through the contact device due to the momentum exchanging property, and then the energy produced by impact forces are dissipated by the oil dampers. Parametric experimental studies were conducted using a model consisting of the damper system and the RC slab which was impacted by a free-fall weight. The tests show optimum values of consisting elements of this damping system, such as materials of the contact device, mass ratio of the additional mass, damping ratio, spring constants and impact forces. Then, the impact absorbing dampers were installed in an actual bridge, and its suppression effect was measured. The model and field tests show that the new damper system is feasible and effective in reducing the vibration and noise levels.
The efficiency of a seismic energy dissipation device is studied. Steel bellows are connected between girders in a row or between girders and abutments in order to reduce the damage of steel bridges. The characteristics of the bellows are confirmed by loading tests and the results are compared with calculated values by finite element method. Design formulas concerning the yield strength and the yield displacement of bellows are developed, and the properties of the bellows are evaluated by the parametric studies. Furthermore, the effectiveness of the bellows are verified by the dynamic response analyses for simply supported steel girders on metallic bearings as well as for steel continuous girders on rubber bearings.
h2>Chikashi Endo Civil Engineer Kajima Corp. Tokyo, Japan
Kohei Sato Civil Engineer Toda Corp.
The present study is investigated the ultimate behavior of the highly energy absorbing device which is composed of the curved pair members for the seismic response control of bridge structures experimentally and analytically. The effects of the configuration of members and the steel with low- yield ratio of this device are clarified by the numerical FEM analysis. Six specimens with the curved pair members and the straight ones were tested under cyclic axial load. It was shown that the damper device composed of the curved pair members has a highly energy absorption. Numerical seismic response analyses for the steel frame structure installed this proposed damper device were carried out by the nonlinear program. The effect of the high energy absorbing device on the seismic response behavior of frame structures was examined.</p
p>Along side with the fast infrastructure development such as highways, roads and railroad tracks there is increasing stress on protection against noise produced by these line sources.
In general it seems to be the most efficient way to reduce noise by building anti-noise walls along line sources of traffic noise. Anti-noise walls absorb the noise and protect from distribution to surrounding environment. The paper describes possibilities of use of waste from production of technical hemp for production of anti-noise walls with high level of sound absorption. Advantages of these walls are not only good acoustic properties but also lower price and utilization of environmental friendly material. The used technical hemp is easily renewable material source; technical hemp can be substituted by another similar material typical for the particular area or more easily accessible.</p
For small and medium bridges, the problems related to bridge deck joints can be overcome by the form of integral (or semi-integral) abutment bridge. But when adopting asphalt concrete pavement, the conventional integral bridge still has a joint between the approach slab and the approach, which needs maintenance regularly and will eventually cause some local pavement failures and a bump. In order to solve this problem, during the design of the first integral abutment bridge in China, Qingyuan Sijiu Bridge, some special treatments at the bridge approaches, such as the specially designed approach slabs and three-layers of geogrids on them, were applied. Therefore there is no expansion joint on the bridge deck and the approach pavement. The successful operation of the bridge in the past three years has proved that the techniques used in this project are effective. Theoretical analysis and experiments are also presented in this paper.
Integral abutment bridges are bridges without any expansion joints, and their largest benefits are the lower construction- and maintenance costs. In order to build longer integral bridges it might be necessary to allow plastic hinges to be developed in the piles. Lateral thermal movements are the major reason to plastic deformations, and since temperature variations are cyclic it has to be proved that low-cycle fatigue will not occur. A simulation of the pile strain spectra should be able to take into account the strains caused by temperature variations and traffic loads. Such a model has been created from real temperature data and traffic loads measured by Bridge-Weigh-In-Motion technology. Monte Carlo simulations have been performed in order to simulate daily and annual temperature changes as well as the varying traffic loads. Piles strains have been calculated, and their fatigue effect has been evaluated.
For bigger concrete bridges the jointless construction hasn't been established up to now. Concerns regarding the durability still exist since constraint stresses as a result of temperature alterations and shrinkage lead to crack initiation. With the use of the new flexible abutment these restraint stresses and occurring cracks can be reduced significantly. An efficient decoupling of abutment and subsoil is reached by introducing a buffer layer of polystyrene and a geogrid reinforced backfill. Full size tests and non linear calculations show that only little deformations arise at the backfill material.
In the last few years, the integral abutment bridge (IAB) concept has become quite common. It is, incidentally, not a newly developed concept, its formulation dating back at least to the 1930s, in order to deal with long-term structural problems frequently occurring with conventional bridge design. At present, the IAB concept is generating considerable interest among bridge engineers because of the enormous benefits due to elimination of expansive joints and reduced installation and maintenance costs. The superstructure of integral abutment bridges is made continuous through a composite cast-in-place concrete deck slab over prestressed concrete or steel girders and continuity diaphragms, and the system constituted by the sub- and the super-structure acts as a single structural unit.
A usual and important problem in the design of IABs is how to deal with the soil-structure interaction behind the abutments or next to the foundation piles: this can be considered as a fundamental aspect for the thorough understanding of this type of structures, which requires iterative and nonlinear analysis. In this paper, a 2D simplified finite-element model of a real 400 meters long IAB, built in the Province of Verona-Italy, will be implemented and used to perform non linear analysis on the bridge. Then, based on the results obtained from a parametric study on the IAB, the analysis of effects of soil-pile interaction and the abutment size will be carried out to find out the relative key parameters in IABs design.
The study deals with the development of long jointless bridges with a focus on soil-structure, interaction. The instrumentation of Haavistonjoki Bridge was completed in the autumn of 2003. The data were collected by monitoring altogether 191 gauges installed in the bridge structures during construction. The instrumentation was used to measure, for instance, the abutment's horizontal displacement, abutment rotation, abutment pile strains, earth pressures behind abutments, superstructure displacements, frost depth, and air temperature. Haavistonjoki Bridge is a 56 m long continuous 3-span slab bridge. The measured earth pressures were compared with calculated pressures. The bridge over Leduån is a single span composite bridge. The cast-in-place concrete deck acts together with two steel beams. The 40 m span bridge is very slender with the height of superstructure 1.7 m. Totally 34 measurements were constantly recorded and stored in a period of at least 18 months. The bridge over Edslan has a 19.8 m span and a 7.65 m wide concrete slab. The test results are verified with calculations.
Preliminary results obtained from short term test-loading are used to llustrate possibilities of FEM used to calibrate complex interaction characteristics between a pile and soil in a bridge with integral abutments. The measurements are obtained during the winter season on the bridge over Ledån, Northern Sweden. The bridge is built in 2006 and used for long term monitoring within the international project supported by RFCS. The main objective of the on-going research project is to proposed recommendations for rational analysis and design of bridges with integral abutments.
A numerical case study is presented, which investigates the performance of embedded integral bridge abutments and the maximum magnitude and distribution of earth pressure within the retained soil. The Three Surface Kinematic Hardening model is adopted in the numerical analysis, which successfully reproduced key features of soil behaviour under small strain cyclic loading. The results show that the earth pressures change in a complicated way, while the largest bending moments in the abutment wall increase with cycles at a decreasing rate, with a final value far less than the one derived from current design standards. A number of factors have been investigated and the influences of the wall flexure and soil stiffness are highlighted. The research results will lead to safe and economic design of such structures.
A wireless data acquisition system with radio communication has been tested, both in laboratory conditions as well as on building sites. This system allows connection of 4 strain gauges to sampling units, fixed to the structure and transmitting data to a central station. The initial devices needed serious improvement to assure signal stability and preventing disturbance from other waves by sealed aluminium housing of the units. Laboratory testing showed very good equivalence with wired measurement equipment. The system has been tested further during 5 months on a prestressed concrete viaduct, which showed creep deficiencies. In addition strain was measured on the piers of 2 major concrete viaducts, crossed by high-speed trains. On the same railway line section, accelerations of parts of a large steel bridge were measured with the new equipment. The wireless transmission of signals now seems very reliable and performs at an identical level as classical equipment.
The introduction of the new Class 390 tilting train at speeds of up to 225 kph was considered to potentially subject the existing West Coast Main Line (WCML) bridge stock to novel dynamic effects, including resonance. To mitigate such risks a major study was commissioned by Network Rail in March 2000. A fundamental part of the work scope was a review of the existing bridge deck acceleration criteria in ERRI D214, and evaluation of the potential to enhance the current limits for assessment purposes, to reflect the forms of vibration likely to occur in traditional forms of UK structures.
Shake Table testing commissioned in Germany has allowed trackform in a loaded and unloaded state to be subjected to controlled frequency-acceleration conditions. The tests enabled the potential ballast instability mechanism to be established.
The resultant acceptance criteria link threshold accelerations to the size of the potential area of the unstable ballast zone and takes account of the risks and consequences of instability occurring.
The aim of this project was to analyze the acceptance of glazed constructions by its users and the planner's motivation of its employment. Special focus was laid on the subjective impressions concerning security, intimacy and usability.