bluuebunny/crossref_metadata_2025 huggingface dataset:
Bond Strength of Plain Round Bars Repaired by Epoxy Resin Injection
Authors: Araki Hideo , Kagawa Junichi
Published: October 2011

This paper summarizes an experimental study designed to evaluate the bond characteristics of the plain round bars in low strength concrete of less than 10MPa. A total of 161 pull-out tests were performed to examine the bond strength and the effect of repair with the epoxy resin injection method. The strength levels of the manufactured concrete were between 5 and 8MPa. The other variables were the direction of the steel bars, the thickness of the concrete cover under the bar etc. The test results show that the approximate bond strength of plain bars in low strength concrete was much lower than the allowable design strength in Japan and that the bond strength of plain bars was significantly increased with the injection of epoxy resin.
Non-destructive technologies for the maintenance of underground utilities.
Authors: Di Sivo Michele , Ladiana Daniela
Published: October 2011

Public administrations have to guarantee and improve the utilities performance, while minimizing the financial and environmental costs, by means of methods and tools which optimize the process itself in order to carry out constant improvements within the level of the services delivered as well as of the infrastructure sustainability.

In such a context, the development of non-destructive technologies for mapping, diagnosis and rehabilitation of underground infrastructures assumes a relevant role since the need to operate interventions on existing infrastructures – minimizing at the same times the impact on urban functions and environment – find in these ones a satisfactory answer. In the present contribution, we will describe the main non-destructive diagnosis technologies in order to map a network as well as to develop its diagnostic process.
Expansion joints for urban bridges – quiet, reliable and low-maintenance
Authors: Spuler Thomas , Moor Gianni , O'Suilleabhain Colm
Published: October 2011

The bridges that a city needs, and in particular its expansion joints, must be designed and fabricated to consider and satisfy a variety of other needs of the city and its inhabitants in addition to providing a simple trafficable route. In an urban setting, issues such as noise, reliability and ease of maintenance take on special significance, due to the increased importance of the structure and sensitivity of adjacent communities to noise, compared with a similar bridge in a rural setting.

Solutions to the challenges facing the suppliers of expansion joints for urban bridges are presented, including descriptions of the various types of “quiet” expansion joint available, and of ways in which existing or new joints can be made quieter. The importance of using high-quality and innovative materials, in particular for sliding components which are particularly susceptible to wear, is discussed. Use of such materials, in expansion joints which have been designed and tested for long life in demanding conditions, will minimise the need for maintenance and replacement work, thus reducing not only the cost of such works but also the effect of traffic disruption on the local population. Other design factors, such as consideration of seismic events, which if neglected could result in a city’s lifelines being cut at a time of great need, are also considered.
Design Optimization of Road Continuous Girder Bridges
Authors: Grimaldi Antonio , Grimaldi Roberta , Luciano Raimondo
Published: October 2011

The paper investigates the optimizing criteria for most common structural bridges typologies, with respect of some relevant aspects as the behaviour under static and seismic actions; minimization of overall construction costs; flexibility of the choice of the number and the size of spans in a certain fixed range in relation to the geological and morphological constraints, structural durability and maintenance costs; aesthetic optimization and minimization of the environmental impact. Examples of optimization of prestressed concrete and composite steel - concrete girder bridges are illustrated, which take into account aspects and parameters outlined above.
Don Bosco Bridge at Arenaccia: Structure, Art and Architecture
Authors: De Luca Antonello , De Martino Attilio , Lucibello Giuseppe , Mautone Giuseppe
Published: October 2011

In this paper, the realisation of a reinforced concrete variable-thickness skew vault bridge recently awarded a special mention at AICAP 2009 Prize is illustrated. In the paper special attention is focussed on the material used (self-compacting concrete with special mix design to allow casting onto doubly inclined surfaces), on the concrete protection issues leading to choose a full surface protection with the use of mosaics and, finally, to the aspects related to the correct architectural design which involved the proper insertion of the bridge in the surrounding urban environment. In this activity special attention was paid to the aesthetic value of the construction in its entireness.
A Curved Self Anchored Suspension Bridge
Authors: Tognoli Joe , Fitzwilliam Dan
Published: October 2011

San Diego has recently built a new baseball stadium in the heart of the downtown area of the city. As part of an attempt to revitalize the area, the city has commissioned a landmark pedestrian bridge from the new ballpark – over the local trolley tracks, over several sets of freight train tracks, and over a busy downtown thoroughfare – to the recently expanded convention center and the San Diego Bay. The bridge design is a self-anchored suspension bridge with a single inclined pylon. The main span of the bridge is 108m and the pylon is 40m tall. The pylon is inclined at a 60 degree angle from the horizontal and leans over the deck to support the single pair of suspension cables. 34 individual suspenders attached to the main cable support the deck from the top of the railing at one edge of the deck only. The unbalanced support conditions generate a large overturning moment due to dead and live loads on the deck. To balance this overturning moment, the bridge is horizontally curved in plan and a longitudinal tendon is placed at the top of the railing. The radial force generated by the tendon above the deck elevation generates a restoring moment which balances the forces in the bridge deck. The bridge will complete the link between the downtown and the San Diego Bay as well as serving as an icon to the city of San Diego.
The alignment, the link between the bridge and the landscape
Authors: Low Angus
Published: October 2011

The visual composition of a bridge in a landscape can be much affected by the alignment of the route which is carried by the bridge, so the alignment is a significant part of the design. The relationships are discussed between the alignment and the landscape, between the bridge and the landscape and between the bridge and the alignment. Past projects are used to demonstrate the points being made.
Analytical Study on Seismic Performance of Column with Secondary Wall
Authors: Noguchi Hiroshi , Kashiwazaki Takashi
Published: October 2011

In this study, 3D non-linear finite element analyses were conducted under repeated loading, additionally involving imaginary specimens, on reinforced concrete columns with secondary walls subject to a horizontal force, using test specimens, used in previous experiments, for which existence of eccentric joints or partial slits are the variable factors. The results were then compared to experimental results and the analysis method was examined. Investigations that include 3D observations were conducted on items for which experimental observation is difficult such as stress distribution, failure mechanisms, and cumulative strain energy consumption. Effects of secondary walls and slits on the seismic properties of column members were studied in detail.
Mechanical effects of floods on river bridge pier foundations
Authors: Federico Francesco
Published: October 2011

Limit states of the soil (G)–foundation (F)– river bridge pier (P) system, potentially occurring during a flood, are analysed. An original constitutive model (c.m.) first allows to simulate the displacements of a rigid, shallow F resting on compressible G, subjected to vertical, horizontal forces and destabilizing moments transmitted by P. The tilt and the stability of the G-F–P system are then modelled on the base of the c.m., by taking into account the complex relationships among the tilt of P, the scour of G and the hydrodynamic forces (horizontal force on P and uplift on F). It is shown that the tilt of P may increase towards a stable value, or reach a critical value (rotational instability) that occurs before the bearing capacity of the F–G sub-system is achieved.
Optimisation of the acquisition points in wind tunnel pressure measurements
Authors: Facchini Luca , Bartoli Gianni , Procino Lorenzo , Borsani Alessandra
Published: October 2011

In order to optimize the structural design of buildings it is often convenient to recur to wind tunnel tests on scaled models, including loads and pressure measurements. While performing pressure measurements models have to be equipped with a limited number of sensors; one of the problems to be faced during the setting-up of the tests is to determine the optimal number and placement of the pressure taps.

It is proposed a method that uses statistical techniques able to reconstruct the pressure time histories in real scale, in the zones between the investigated positions. Finally the optimal number and position of the measuring points is analyzed by means of a technique based on neural networks.
The Actions of Axial Loads on Masonries – Ultrasonic Verifications and Statistical Analysis of Obtained Data
Authors: Khodaverdian Alireza , Shomali Behzad
Published: October 2011

Among the different non-destructive tests used to carry out an exhaustive survey about the mechanical and durability characteristics of a masonry made of solid tile-bricks, the ultrasonic method has experienced a wide diffusion thanks to its low costs and to its easiness of use; the method essentially consists in detecting the propagation velocity of ultrasonic pulses propagating through a solid to be acoustically characterized. The solid considered in this theoretical and experimental survey has been obtained from a meaningful statistical sample of masonry units made of solid tile-bricks blocks bound together by cement mortar. The experimentation made use of one set of masonry panels, prepared for this purpose, consisting of solid bricks of UNI type (size of block cm 5.5 12 25), arranged according to the thickness or according to a “one-head” pattern scheme. The total height of the samples of the set is 48 cm inclusive of cement mortar layers. The issues which came out during the statistical analysis of the experimentation results are basically of inductive nature: the purpose is to move from a limited and incomplete knowledge of the values of the propagation velocity quantity measured on the masonry, to get the most suitable definition of the possible distribution of all the values that can be reached by velocity under stress conditions imposed by the strength applied on the masonry at the moment of measuring the ultrasonic wave.

The strength is generated by a press used to simulate the conditions imposed on the axial strength of the specimens under investigation.

The purpose of this work is to present a procedure for the interpretation of the data in order to assess the compressive stress state by using the ultrasonic velocity variable obtained from masonry samples expressly prepared for this experiment.
Identification Of Uniform Hazard Time Histories for Seismic Design
Authors: Trombetti Tomaso , Gasparini Giada , Silvestri Stefano
Published: October 2011

This paper focuses on the identification of groups of uniform hazard (acceleration) time-histories for Performance Based Seismic Design applications. In detail, on the basis of a peculiar Probabilistic Seismic Hazard Analysis, the characteristics that a group of earthquake inputs must possess in order to be associated to a given exceedance probability are obtained. The proposed procedure takes advantage of the information carried by the “epsilon” parameter, and is rooted on a separate treatment of the aleatory variability and the epistemic uncertainty considered in the hazard analysis. The analytical developments allow to identify a condition for the spectral ordinates (“spectral cloud”) of the acceleration time histories, which is valid for a number of structural periods at once, and to quantify (in terms of coefficient of variation of the spectral ordinates) the randomness associated to the epistemic uncertainty (error in the spectral acceleration prediction law).
Influences of the Urban Environment on the Emme Tunnel
Authors: Menétrey Philippe , Wyss Markus
Published: October 2011

The 47 km long new railway line between Bern and Zérich is one of the main part of the project Rail 2000 developed by the Swiss Federal Railway Company. Near Kirchberg, this new railway line is crossing the Emme river, in addition the busiest highway of the country, local roads, an existing railway bridge, various public utilities and two towns. Due to the density of this urban environment and, as most of the crossed infrastructure has to remain in service during construction, a tunnel of 1628 m length in granular soil was planned.After defining all project parameters, general concepts were developed considering the environmental aspects. A major issue was the concept for waterproofness of the tunnel which is ensured by the concrete liner itself without membranes. Thus, retrofitting limited lifetime waterproofing will be avoided.The density of the environment asked for different construction methods. One section of the tunnel was built in standard cut-and-cover technique with a vault profile. With increasing depth of the construction pit, tunnel construction was executed between anchored sheet piling and in areas with groundwater level on top of an underwater-base concrete slab. The middle section of the tunnel was built using a top-down construction method with a rectangular tunnel cross-section. After the top slab was poured between slurry walls the previous terrain was re-established in order to minimise interference with the highway and the river. Soil excavation below the top slab was performed applying air overpressure to lower the groundwater level.The complexity of construction methods, construction staging, environmental, soil, and groundwater conditions required non-linear finite element simulations for estimation of interaction between tunnel and existing structures. The model which was used is briefly described and a comparison with field measurements is presented.
The Structural Design of The World’s Tallest Structure: The Burj Dubai Tower
Authors: Baker William , Korista D. Stanton , Novak Lawrence , Pawlikowski James , Young Bradley
Published: October 2011

The design of supertall buildings is typically governed by their interaction with lateral winds and gravity loads. Selection of the building shaping and structural system can greatly affect the wind and gravity behavior of the structure. This paper will consider the case study of the Burj Dubai Tower to demonstrate the design process and philosophy utilized in the design of supertall buildings.
New trends and new models for analysing dynamic interactions
Authors: Crémona Christian
Published: October 2011

Vibration problems in structures is become a major topic for structural engineers due to the slenderness of the designed structural systems. In a classical design approach, loads act on the structures and the structural response is calculated through a model which is usually does not interact with the loading. In the past, the analysis of wind effects on bridges or flexible structures have changed such a calculation approach; flow induced vibrations have highlighted that the studied system was no longer the structure itself but a coupled system including the fluid and the structure.

Such coupled problems are now very common; to date, the last one is certainly the human-induced vibration problems met in footbridges, but seismic design also involves complex models for soil- structure interaction. The interaction between vehicles and bridges, for high speed tracks, is a topic becoming more and more pregnant. All these coupled vibration problems require sophisticated techniques, but more drastically new modelling approaches for structural engineers. This keynote will address the new trends for analysing dynamic interactions; emphasis will be nevertheless given to major problems met today in bridges: human-induced vibrations and flow-induced vibrations.
Personal Involvement in early US Cable-Stayed Bridges
Authors: Svensson Holger
Published: October 2011

The personal involvement of the author in the early US cable-stayed bridges is outlined, including the Pasco and Huntington concrete bridges and the Burlington and Fred Hartman composite bridges.
Increase of a high rise buildings damping behaviour by applying Large Scale Tuned Mass Dampers
Authors: Meinhardt Christian , Wagner Hans-Georg
Published: October 2011

The following paper introduces the application of large scale Tuned Mass Dampers (TMD) on high rise buildings to increase the buildings structural damping. Therefore the TMD effect and the practical handling of the optimum TMD specification are briefly described. Construction principles and the achievement and testing of the required specifications, as well as the experimental verification of the TMDs effectiveness - measuring the buildings ambient vibrations and using several methods to determine the structural damping – will be portrayed. Finally an example project for a successful and demanding application of a TMD will be introduced.
An Optimal Design of TMD for the Improvement of Fatigue Reliability of Steel- composite High-speed Railway Bridges using Target Performance Approach
Authors: Kim Sung-Jae , Kang Soo-Chang , Park Wonsuk , Koh Hyun-Moo
Published: October 2011

This study investigates the effectiveness of Tuned Mass Damper (TMD) on the fatigue reliability of a steel-composite high-speed railway bridge. The extension of the fatigue life of the bridge brought by TMD designed to reduce resonance-induced vibration is verified. In parametric analyses, the extent of fatigue reliability improvement and the optimal design factors of TMD are studied by using the procedure of fatigue reliability evaluation based on dynamic analysis. Considering the uncertainties of the train velocities and the damping ratio of the high-speed railway bridge, a series of dynamic analyses is performed for the bridge subjected to moving loads. Stress time histories are determined from the time domain analysis at the critical structural components of the bridge. The rain-flow counting method is adopted to obtain a number of stress ranges and cycles from time history responses. Based on these stress ranges, cycles and intended service life, the fatigue failure probability is evaluated through the S-N curve-based approach. As a numerical example, a 40 m- span steel-composite bridge is considered. The effectiveness of TMD on the fatigue life of the bridge is examined and the results are presented. Moreover, the optimal design parameters of TMD including the mass ratio, natural frequency and damping ratio are investigated and determined.
Use of CFRP to Strengthen Lap Splices of Reinforced Concrete Columns
Authors: Kim Insung , Jirsa James O. , Bayrak Oguzhan
Published: October 2011

The use of Carbon Fiber Reinforced Polymer (CFRP) materials to repair and strengthen inadequate lap splices in square and rectangular reinforced concrete columns is presented. Four large scale columns (three square columns and one rectangular column) were tested to examine the effectiveness of the rehabilitation methods for improving lap splice behavior. The test results show that a combination of CFRP jackets and CFRP anchors effectively confined the lap splices of the columns. The tensile capacity of the longitudinal bars was developed and the deformation capacity of the columns was considerably improved. The strengthening methods of RC columns using CFRP may provide a solution for improving structures vulnerable to progressive failure.
Flexural strengthening of beams using externally bonded plates: advanced optical measurements at the beam-to-plate interface
Authors: Schumacher Ann
Published: October 2011

In a first test series, small-scale steel beams reinforced with adhesively bonded carbon fibre reinforced polymer (CFRP) plates were subjected to four-point bending. Phase-stepping 3D-digital speckle pattern interferometry (DSPI) was employed to measure the strain concentrations near the end of the CFRP plate, with a special focus on shear and normal strains. Furthermore, a refined finite element analyses (FEA) of the strengthened beam was carried out to predict these strains.

Comparisons between measured and calculated strains have confirmed a strong variation of shear strain across the adhesive layer. The FEA has also shown the much higher normal strains present at the adhesive-steel (AS) interface than at the plate-adhesive (PA) interface. This difference has been suggested as the reason why debonding failure more commonly occurs at the AS interface rather than the PA interface. In a second study using optical measurement capabilities, a reinforced concrete (RC) beam was strengthened in flexure using a CFRP plate and tested in a four point bending test. In this study both conventional measurement techniques as well as an optical 3D image correlation system (ICS) were used to measure the displacements at the tension face of the

beam. Results from the ICS measurements have shown interesting and unexpected slip distributions, in particular at the CFRP plate ends. Further experimental and analytical study is needed to confirm and understand this behaviour.
RC Beams Strengthened with FRP Systems – Results in Dapped-ends and Increase of Flexural Capacity
Authors: Nagy-Gyorgy Tamas , Stoian Valeriu , Dan Daniel , Daescu Cosmin , Diaconu Dan , Demeter Istvan
Published: October 2011

The paper presents a description of the theoretical studies and the results of the experimental tests carried out on reinforced concrete beams with specific strengthening systems. In the first part investigations made on pre-stressed concrete beams’ dapped end retrofitted with various FRP systems were described. The second part is dedicated to RC beams flexural capacity increase by applying FRPs.
Large-Bar Connection for Precast Bridge Bents in Seismic Regions
Authors: Pang Jason , Stanton John , Eberhard Marc
Published: October 2011

The use of precast concrete components in bents can accelerate bridge construction, but, their use in seismic systems is challenging. Such systems must have connections that are both easy to assemble on site, and have sufficient strength and ductility during earthquakes. A precast bridge bent connection, which uses a small number of large bars anchored in ducts, meets these requirements. Cyclic lateral load tests conducted on subassemblies of the system demonstrated that it has strength and ductility similar to those of a comparable cast-in-place connection. Intentional debonding of a short length of the bars had little effect on performance.
Slip in Hanger Cable Anchorages of Dintelhaven Railway Bridge Rotterdam
Authors: Snijder H. H. (Bert) , Hesselink Bert H. , Noorlander K. , Berenbak Jacques , Spoelstra J. S. (Jaap)
Published: October 2011

The Dintelhaven Railway Bridge in Rotterdam, The Netherlands is a stiffened bowstring steel bridge spanning 170 m. Its hangers are formed by cables consisting of parallel strands attached to the arch and the main girder through ‘traditional’ anchorages. Shortly after erection of the bridge, a load test was performed before taking the bridge in operation. It turned out that quite a number of strands of the hanger cables slipped through their anchorages. The main cause turned out to be ‘sticking together’ of the outer wedge surface and the cone shaped hole surface in the anchor plate. This yields a high coefficient of friction between wedges and cone shaped hole surface. Increasing the cable force does not cause the wedges to enter the cone shaped hole any further (as intended), but causes the strands to slip through the wedges. The paper describes these phenomena in detail and gives a practical solution to overcome the problem of slip in cable anchorages.
Numerical and experimental investigation on real temporary structures useful for incremental launching bridge construction
Authors: Anania Laura , Badalá Antonio , D'Agata Giuseppe
Published: October 2011

The study is aimed to evaluate the influence of the construction quality on the buckling load as well as on the bearing capacity of the real sub-structural system provided in order to keep the cantilever moment to a reasonable magnitude, during continuous post-tensioned multi-span bridge casting. The clamping bolt quality as well as the stiffness of the flanged joint of the two steel truss piers, which had collapsed during the â€œPorcaria bridgeâ€ construction, are studied. At first, some laboratory tests were carried out on flanged joint specimens. Later, a numerical investigation was carried out on the real model of the towers by varying the quality of the clamping bolt. The data obtained show how the buckling load is highly influenced by the correct erecting of the tower. In fact, a lower stiffness of the flanged link or an insufficient clamping bolt might produce safety coefficient lower than unity. Besides, the perfect accordance between numerical and experimental investigation gave us the possibility of a more accurate design of the temporary towers.
I-205 Glenn Jackson Bridge-Bike Path Deck Panel Investigation, Portland, Oregon, USA
Authors: Koru Burak , Wagner Donald E. , Hinman John , Topark Ngarm Pattanapong
Published: October 2011

The I-205 Glenn Jackson Bridge is more than 11,000’ long and connects the States of Oregon and Washington across the Columbia River. The Northbound and Southbound bridge structures each include four travel lanes plus shoulders and provide one of the most important highways for the City of Portland and the region. The bridges provide access to Portland International Airport and many commuters use this highway for their daily travel. Both bridges include variable depth post- tensioned concrete box girders that were segmentally constructed in 1983. Span lengths vary with main spans of 600’. The Northbound and Southbound bridges are curved with varying radii over the 2 mile length. Although the bridges were cast concentrically, the bike path connecting between the two bridges has cracking and out of plane distortion, causing concrete to crack and spall, leading to holes forming at some locations. Also, some the deck panels between the two structures have shifted from their original bearing locations, leaving minimal or no bearing length for additional relative movement. At several locations, steel plates have been installed to maintain safe use of the path.

Two site inspections were performed to observe, record and locate the major damage to the path. Global positioning system methods were used to locate the damaged sections of the bike path. This information was then linked to the structural analysis results. Thermal and shrinkage strains and the non-alignment of the Northbound and Southbound bridge expansion joints were determined to be the cause of major damage to the bike path deck panels in locations that were in close proximity of the bridge expansion joints. Several possible solutions to repair/alleviate the bike path damage were proposed to the Oregon DOT for their use.
SEI Pre-Standard and Commentary on Disproportionate Collapse (Part I)
Authors: Marchand Kirk , Williamson Eric , Stevens David , Crowder Brian
Published: October 2011

Guidance in EN 1990 and EN 1991 provides preliminary guidance for determination of appropriate design approaches for mitigation of progressive collapse. This preliminary guidance is somewhat devoid of detail with respect to applicability and analysis. It also does not lend itself well to consensus based professional and industry approaches extant in the US. The SEI Progressive Collapse Standards and Guidance Committee is developing guidance more applicable to the US approach, and has developed preliminary recommendations for risk determination and mitigation strategy applicability.
Design and Evaluation of Facade Access Equipment for Tall Buildings
Authors: Lewis Jonathan , Schmidt Mark
Published: October 2011

Access to building facades is necessary for routine maintenance, window cleaning, and repairs. Structural engineers are often asked to design facade access systems for new or existing buildings or to evaluate various facade access equipment. Drawing upon relevant case histories in which dedicated facade access equipment was inspected, tested, and/or designed for a number of high rise buildings, this paper presents key design and evaluation criteria for such equipment, and offers general recommendations and guidance for navigating often-contradictory codes and regulations.
European Guideline for Assessment of Existing Railway Bridges
Authors: Jensen Jens S. , Casas Juan R. , Wisniewski Dawid F.
Published: October 2011

This paper gives a general overview of the "Guideline for Load and Resistance Assessment of Existing European Railway Bridges - advices on the use of advanced methods" that is providing guidance and recommendations for applying the state-of-the-art knowledge for assessing existing railway bridges. The Guideline has been recently developed within the European Project Sustainable Bridges. The paper highlights the most advanced solutions proposed in the Guideline, which are novel compared to the current practice. Moreover, it tries to gives some guidance to other recommendations recently developed in Europe regarding inspection, condition assessment and monitoring of existing railway bridges.
Structural Engineering of the 600 m Chicago Spire
Authors: Tomasetti Richard , Burns Joseph , Scarangello Tom , McLean Dave , Browne Garret , Steele Nicholas
Published: October 2011

The Chicago Spire has a very innovative structural system that is a true integration of architecture and engineering. The spiral shape of the tower is ideal for improved wind performance and the composite structural frame has optimized the use of a concrete core and steel framing for one of the most significant tall buildings of this century. A unique circular outrigger system, that does not require thru core struts, and the use of high strength concrete all contribute to the feasibility of this future landmark. The engineering analysis included a sequential construction analysis of the building with time dependent material properties to account for the effects of elastic shortening, creep and shrinkage of the concrete.
Trends, Drivers and Challenges in Tall Buildings and Urban Habitat
Authors: Wood Antony
Published: October 2011

This paper outlines the major influences on tall building design in the early stages of the 21st Century. At this unprecedented time in terms of the scale and number of tall buildings being built globally, the paper charts some of the recent trends in tall buildings, and suggests some of the drivers. It also looks to the growing challenges in the future and, through design-research case studies undertaken by the author at the Universities of Nottingham, UK and the Illinois Institute of Technology, Chicago, suggests design responses to face some of these challenges.
Dubai Tower Doha
Authors: Merrick John , Haysler Mike , Davids Andy , Popovic Darko
Published: October 2011

Dubai Tower Doha is a 438 metre tall tower building, including a 36 metre spire, currently under construction in Doha, Qatar. The estimated date of completion is 2010. The tower provides accommodation for retail, office, hotel and residential uses over 90 levels above ground and five levels of basement car parking. The gross floor area of the tower and adjacent podium complex is approximately 280,000 m2, including basement parking. The project architect, structural engineer and MEP services engineer is Robert Matthew Johnson Marshall (RMJM). Hyder Consulting is sub-consultant for the structural design of the tower.

At completion, Dubai Tower Doha will be amongst the world’s ten tallest buildings.
Curved cable-stayed bridges
Authors: Tadla Janusz , Biliszczuk Jan , Barcik Wojciech , Onysyk Jerzy , Sadowski Krzysztof
Published: October 2011

Designing of curved cable-stayed bridges allows to increase safety of its users (drivers). They also allow to adjust bridge to the existing or planned road communication configuration. Some unexpected behaviour of such structures may appear during its exploitation. Therefore it is necessary to gather information of ways of designing and non-typical behaviour of such bridges.

Two curved cable-stayed bridges located in Poland are presented in the paper, including description of the structures, the way of their construction and their behaviour during exploitation and filed tests. The first one is a cable-stayed bridge in Skorogoszcz (Poland), which has two spans of 59.75 m each. Pylon is made of steel and the deck has composite structure: three beams are made of steel and plate is made of concrete. The second bridge is a viaduct along National Road No. 94 over the A4 highway in Wykroty. It is a continuous double span (45.47 + 45.28 m) cable-stayed structure with a prestressed concrete deck and the V-shaped pylons are made of steel.
Sutong Bridge-A Cable-stayed Bridge with Main Span of 1088 Meters
Authors: You Qingzhong , He Ping , Dong Xuewu , Zhang Xigang , Wu Shouchang
Published: October 2011

DOI: 10.2749/222137908796219372 also seems to point to this article

Sutong Bridge is the longest cable-stayed bridge in the world with a main span of 1088 meters. In this paper, design and construction concepts are briefly presented. Furthermore, key technologies and innovative achievements are summarized mainly on piled foundation bearing capacity analysis, river bed scour protection and monitoring, superstructure wind-resistance study, mid-span closure method as well as long cantilever structure construction control.
Construction of the Bai Chay Bridge
Authors: Tuchida Kazuteru , Ohno Hiroshi , Nakamura Tomoki , Wakahara Toshihiro , Nagamoto Naoki , Komiya Masahisa
Published: October 2011

The Bai Chay Bridge, spanning a strait within sight of Ha Long Bay, Vietnam’s premier World Heritage site, has the world’s longest center span length of 435 m, as a single plane cable-stayed prestressed concrete bridge, with a bridge length of 903 m.

The foundations for the main piers were constructed by the pneumatic caisson method. Form travelers were used for the cast-in-situ box girder erection by the balanced cantilever method. The main pylons, which extend 91,5 m in height above the deck level were constructed using a climbing formwork system.

The box girder is lightweight with internal steel pipe bracing and prestressing tendons. The design wind speed for the bridge is 50 m/s. Technologically advanced vibration control devices for the stay cables and the pylons were incorporated into the construction.
Optimizing the design process of complex structures
Authors: Kobarg Joerg , Schmidt Thomas
Published: October 2011

„i-BID Archive“ stands for Interactive Building Information Documents Archive. It is a software application based on PDF technology that automatically generates an interactive archive from the data of a 3D structural model. Within the archive all information pertaining to a construction can be stored together in form of electronically linked PDF documents. This eliminates the annoying walk to the archive, because all the data will be available at a mouse click. “i-BID Archive” can easily import any changes to the structural model into the PDF drawings and PDF calculation documents. In this way, the high quality archive can be updated with very little effort during the life cycle of the construction. Hence, “i-BID Archive” is interesting for builders and planning engineers when planning and maintaining complex structures.
Controlled Rocking of Steel Frames as a Sustainable New Technology for Seismic Resistance in Buildings
Authors: Hajjar Jerome , Eatherton Matthew , Deierlein Gregory , Ma Xiang , Pena Alejandro , Krawinkler Helmut , Billington Sarah
Published: October 2011

During large earthquakes, traditional seismic lateral resisting systems can experience significant damage, which is distributed throughout the building, and residual drifts that make it difficult and often uneconomical to repair. Higher performance systems that allow a structure to be easily repaired after an earthquake represent a more sustainable method of construction. Controlled rocking of steel frames using replaceable energy dissipating fuses is a new technology which virtually eliminates residual drifts and concentrates structural damage in replaceable fuse elements, thus making repairs easier and less-costly after an earthquake.

A multi-institution, international research project is underway to develop and validate the performance of the controlled rocking system. It is expected that the controlled rocking system will provide the structural engineering community with a high performance, more sustainable alternative to traditional seismic lateral resisting systems.
Mechanical Properties of Biocomposites for Sustainable Construction Practices
Authors: Christian Sarah , Billington Sarah
Published: October 2011

Biocomposites are structural materials made from renewable resources that biodegrade in an anaerobic environment after their useful service life, thus reducing construction-related waste. These materials are being researched and developed to replace less eco-friendly structural and non- structural materials used in the construction industry. In this research, the mechanical behavior of a cellulose acetate hemp fiber (fabric) biocomposite material has been characterized experimentally. The biocomposites were found to have mechanical properties similar to structural wood. Measured material properties were used to evaluate the applicability of laminate plate theory and a nonlinear model was validated to predict biocomposite laminate plate response in tension. The biocomposites studied have the potential to be used for scaffolding, formwork, flooring, walls and for many other applications within buildings and within the construction process.
R1664 Suspension Trail Bridge Using Sustainable Materials
Authors: Miller Bradley
Published: October 2011

Construction of the 27.5 meter (m) suspension pedestrian bridge over Rattlesnake Creek near Missoula, Montana provides an aesthetic and innovative link in the city’s trail system. Engineers reviewed historic U.S. Forest Service trail suspension-bridge construction, relying on proven technology while incorporating small diameter roundwood (smallwood) salvaged from bug-killed lodgepole pine, along with other sustainable design materials. Lattice stiffening trusses, floorbeams and braces, constructed from small diameter roundwood, qualified the bridge for grants including

U.S. Forest Service funds. They also provide an aesthetically pleasing context sensitive tie with the forested environment. Other sustainable materials used in the bridge construction include 100 mm x 300 mm composite decking from sawdust and recycled plastic, and an 18 mm thick rubber mat wearing surface from recycled tires.
Structural Design for Beijing Grand MOMA
Authors: Xiao Congzhen
Published: October 2011

Beijing Grand MOMA sited adjacent to the center of Beijing, has 9 towers, one kindergarten and one cinema. The 12 to 21 storied towers with frame-core wall structure are divided into 7 structural units, and are linked by 8 bridges at the top. The bridges span from 30m to 55m. This paper introduces the design of basement and foundation, bridges and seismic design of towers.
Trump International Hotel and Tower, Chicago
Authors: Baker William , Korista D. Stanton , Rankin Dane
Published: October 2011

When completed in 2009, Trump International Hotel and Tower, Chicago will rise to a height of
345.6 m (415.1 m including the spire). Designed by Skidmore, Owings & Merrill LLP (SOM) the
92 story Trump Tower will be the tallest concrete building in the United States, and the tallest
building built in North America since the completion of Sears Tower in 1974. New ground is being
broken through a series of high performance concrete mixes designed by Prairie Material Sales, Inc.
and employed by SOM on the project. It is believed to be the first application of 110 MPa selfconsolidating
concrete pumped and placed to an elevation up to 200 meters above grade. The paper
presents detailed structural engineering aspects of the tower design including a description of the
reinforced concrete systems chosen for the project, design for occupant perception of motion due to
wind, design challenges and the creative use of high strength concrete for this landmark tower.
The Tianjin Jinta Tower: 74 Story Steel Plate Shear Wall Tower
Authors: Mathias Neville , Sarkisian Mark , Long Eric , Huang Zhihui
Published: October 2011

The 329.6 meter tall 74-story Jinta Tower in Tianjin, China, is expected, when complete, to be the tallest building in the world with slender steel plate shear walls used as the primary lateral load resisting system. With an overall aspect ratio close to 1:8, the design challenge for this tall building was to develop an efficient lateral system capable of resisting significant wind and seismic lateral loads, while simultaneously keeping wind induced oscillations under acceptable perception limits. The paper will describe the genesis of the structural system selection considering various available options and significant aspects of the analysis, design, testing and proposed construction. US and Chinese codes and standards, current on-going research and development, and project specific testing were integrated to develop the analysis and design procedures used.
Brief on the Construction Planning of the Burj Dubai Project, Dubai, UAE
Authors: Abdelrazaq Ahmad
Published: October 2011

The Burj Dubai Project will be the tallest structure ever built by man; when completed the tower will be more than 700 meters tall and more than 160 floors. The early integration of aerodynamic shaping and wind engineering considerations played a major role in the architectural massing and design of this residential tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria. While the focus of this paper will be on the construction planning of the tower, this paper will briefly present an overview of the structural system of the tower’s design and construction, which are integrated from the early design concept.
Comparison of the Structures for two High-rise Buildings in Madrid
Authors: Gómez Navarro Miguel , Martínez Calzón Julio
Published: October 2011

Four high-rise buildings have been built close together between 2004 and 2008 in Madrid (Spain). The structures of two of these buildings,Torre EspacioandTorre Sacyr-Vallehermoso, have been designed byMC-2 Estudio de Ingeniería, who has been responsible too of the site management.

Both buildings have approximately the same height and surface, as well as the same wind exposure conditions. However, the architectural choices imply quite dissimilar external shapes and internal distribution, resulting in a significantly different behaviour under wind loads. In addition, and due to the preferences of the owner, it was decided thatTorre Espaciohad to be mainly a reinforced concrete structure. The appropriateness of both structural systems, correlated to their speed of construction, cost, facade design and architectural requirements are compared in the paper.
Strengthening of the I-39 Bridges over the Kishwaukee River
Authors: Furrer Martin , Etemadi Mahmoud
Published: October 2011

The Kishwaukee River Bridges, built in 1980, carry interstate I-39 over the Kishwaukee River Gorge south of Rockford, Illinois. These twin bridges consist of five spans of precast, post- tensioned segmental concrete box superstructure with a typical span length of 76.3 m. During the balanced cantilever erection of the southbound structure, the epoxy applied to the segment joints did not properly harden creating excessive stresses in the single-key shear keys. A retrofit was carried out before the structures were opened to traffic involving placing stainless steel dowels set in epoxy across the overstressed joints.

The box girder webs have been displaying continuous cracking and crack growth. A structural investigation determined that the passive method used to remedy the shear capacity deficiencies has left large forces in the shear keys responsible for the stress cracking observed in the bridge causing continued deterioration. Parsons proposed rehabilitation and strengthening of these structures using external post-tensioning tendons placed inside the box girders which actively reduce the shear forces and principal stresses in the box girder webs.

This paper focuses on the strengthening concept employed and special details developed to allow installation of the external tendons with minimal disturbance to the box girder’s concrete and the embedded post-tensioning. Other highlights include a discussion of the supporting measures implemented to assure long-term safety and durability of these structures like the fixed anti-icing system that eliminates the need to use salt on the bridge deck.
Remarkable Strengthening of an old Steel Highway Bridge
Authors: Unterweger Harald
Published: October 2011

The paper deals with the remarkable strengthening of a continuous steel plate girder bridge with three spans, built in 1939. Due to increased loads, unscheduled material properties (undersized yield stress) and detected cracks near the ends of cover plates, a lack of load carrying capacity for the main girders was decided. Based on fracture mechanics it was determined that an extensive unloading of the existing structure was necessary - excluding conventional strengthening. Therefore an exceptional solution was chosen. Additional main girders are situated on the upper side of the bridge deck, connected by prestressed tension rods for unloading the existing structure. First the three design variants for the new main girders (plate girder, truss, arch) are presented, analysed in a preliminary study. Finally the chosen solution of a tubular tied arch, selected also due to aesthetic reasons, is represented. The design concept, the structural design and erection are shown.
Upgrading mainland Europe’s oldest suspension bridge
Authors: Adriaenssens Sigrid , Wouters Ine , de Bouw Michael
Published: October 2011

In the beginning of the 19th century mainland Europe witnesses the construction of its first suspension bridges. The advent of two World Wars blew up or bombarded most of the strategic ones. Therefore the history of mainland Europe’s suspension bridges can mainly be illustrated by decorative bridges in private parks. This preliminary structural study looks at restoration and strengthening methods to make the 20.5m span Wissekerke bridge, mainland Europe oldest suspension bridge, comply with current concepts of safety. Due to ill-maintenance and

deterioration over decades as well as a function shift (from private to public use), the bridge does not fulfil current European norms for pedestrian bridge design. A strengthening strategy is discussed that targets maximum public use, optimal preservation, least visual impact, easy future maintenance and durability. This design preserves and restores all authentic elements (such as cast iron masts, wrought iron suspension chain, back stay and railing) and replaces the structurally inadequate non authentic deck structure with a shallow barely visible steel box girder. This girder carries its own and superimposed dead load as well as all the variable loads. It is designed to guarantee appropriate dynamic behavior. The authentic suspension structure is connected to the girder through a series of vertically and longitudinally sliding connections. These connections avoid load transfer from the new structure (girder) to the authentic structure (suspension system).