bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculation and construction study for the Novel Twin-Deck Cable- Stayed Bridge with shared pylon
Authors: Yu Xiangmin , Chen Dewei
Published: March 2021

Twin-deck cable-stayed bridge with shared pylon (TDBSP) is an innovative structural arrangement captured with complex mechanical performance and highly interaction effect between two bridges, as the deck layouts are asymmetrical and two bridges share one merged pylon leg. This paper explores the calculation and construction methods of TDBSP, based on the record-breaking Rod El Farag Axis Bridge. Single-beam model (SBM) and beam-plate model (BPM) are firstly established, and the numerical results are compared with field surveys as validations. Then, the interaction effect of two bridges during construction are studied, and a comparison of synchronous construction method (SCM) and asynchronous construction method (ASCM) are investigated during the construction of TDBSP.
Calculation of influence line using regular traffic for improving bridge weigh-in-motion under variable vehicle speed
Authors: Takeya Kouichi , Yoshida Junji , Mori Junki
Published: March 2021

In this study, an influence line of girder deflection of the bridge was calculated for the initial calibration of Bridge Weigh-in-Motion (B-WIM). The deflection responses were obtained from the proposed integration process using the baseline correction. Optical flow analysis was applied using a video camera to adapt to the variable vehicle speed and precisely measure the location of vehicles on a bridge. A foreground mask using the Gaussian mixture model and a Kalman filter was then applied to identify the vehicles. A calibration process of B-WIM was proposed using the iteration process to optimize the influence line of deflection using local buses in regular traffic. Finally, the axle weights of a weight-known test truck were analyzed by monitoring with the video camera and acceleration sensor. Compared with conventional B-WIM methods, the proposed method has demonstrated higher adaptability in variable vehicle speed.
Finding the optimum layout for cable-stayed bridge in conceptual design
Authors: Soppela Sami , Järvenpää Esko
Published: March 2021

In the cable-stayed bridges the primary cost components of the load-bearing material, in the longitudinal direction of the bridge, are the cables. The longer the bridge, the higher the share of the costs of the load-bearing material. The quantity of the cables and the cost optimized cable and tower topology can be reliably solved, already in very early design stages, using a simple calculation method proposed in this article. The cables are considered as a curtain structure and the cable forces are calculated for the permanent load balance. The solutions are performed mathematically by using integral calculus based on a force length method and a unit bridge concept. The results provide a good idea of the optimum pylon height for both one-pylon and two-pylon bridges. The optimum pylon height depends on the span ratio and the chosen cable system.
Analytical study on repair method for steel I-girder bridges with corrosion damage considering its structural system behavior
Authors: Oura Ryoga , Yamaguchi Takashi , Arimura Kentaro
Published: March 2021

Bridges are composed by many structural members which interact with each other to resist against various load combinations. Considering damage repair of one of its structural members, the relationship between the recovery of the individual load-carrying capacity due to the repair of a single member and the improvement of the load-carrying capacity of the structural system is not clear. In the present study, a full-scale FE analysis has been conducted for a steel I-girder bridge system with corrosion damages which have been repaired. The analysis considered, the structural system behavior, varying the repaired areas and the type of patch members. From the analytical results, it was found that, compared to the method in which the damaged portion is completely repaired, the amount of repair can be reduced by taking into account the structural system behavior and partially repair both the damaged and the adjacent intact girders.
Review of detail categories of lattice girder node joints of EC 3
Authors: Bartsch Helen , Feldmann Markus
Published: March 2021

The paper deals with the re-evaluation of detail categories of lattice girder node joints based on fatigue test data. An elaborate database structure has been set up to evaluate the available fatigue test data in a differentiated way. Detail categories of different types of K and N joints have been investigated and re- evaluated based on the developed data base. Geometric influences on the fatigue strength have been analysed and design recommendations are given.
Rose Fitzgerald Kennedy bridge over the River Barrow. Design and Construction of a long span extrados bridge
Authors: Sanchez Marcos Sanchez , Astiz Suárez Miguel Ángel , Iliff John
Published: March 2021

This paper describes the key elements from early planning to completion of a new bridge over the River Barrow which is part of the New Ross bypass in the south of Ireland. The structure has a total length of 887m, with a span arrangement of 36-45-95-230-230-95-70-50-36m. The two central twin spans are the longest of its kind in the world (extrados with a full concrete deck). The bridge carries a dual carriageway with a cable arrangement consisting of a single plane of cables located in the central axis of the deck. The design and construction focused in providing a structure with long term durability, resilience, and a robust approach to design scenarios using the Eurocodes and state of the art analysis techniques, including extreme events such as fire and ship impact.
Elastic-, inelastic and plastic buckling of curved shear webs in closed box girders with vertical stiffeners
Authors: Van Staen Gilles , Van Bogaert Philippe , Outtier Amelie , De Backer Hans
Published: March 2021

Curved steel panels are widely used in structures such as ships, aircrafts and bridges. During the last decades, plates with an out-of-plane curvature in the cross-section of the bridge are being used, partly to increase the aesthetics. The elastic buckling behaviour of curved plates is not covered by standards of codes for bridge design, resulting in rather conservative solutions. In the current research, there is investigated how curved steel panels used as a web panel in a closed box girder interacts with shear and bending stresses. Therefore, a double symmetric box is numerical simulated in a three point bending test. The first mode shape found by a LBA is used as an initial geometric imperfection, in order to trigger buckling of the webs. It is proven that when increasing the curvature while keeping a similar slenderness ratio, the buckling mode of a plate can change from elastic to inelastic and even plastic buckling. This behaviour is found back in the webs of the closed steel sections. Slender curved plates have an equal load-deflection path as their straight variant. Inelastic and plastic buckling of the webs results yield zones in the web, eventually combined with geometric deformations. The girders with curved webs are sensitive to imperfections in such a way that slender curved panels have a large reduction in initial stiffness with increasing amplitude. On the other hand, moderate or thick curved panels remain their initial stiffness but have a reduction in their ultimate load capacity.
Analysis of economic efficiency for cable-stayed-suspension bridges based on structural applicability
Authors: Son Younki , Nam Wanghyun , Yoo Dongho , Song Sangwon
Published: March 2021

In this study, the major quantities of 8 suspension bridges (SB) and cable-stayed-suspension bridges (CSSB) from 1,000m to 4,500m in midspan were calculated based on the structural validity. Based on the calculated quantity, the economic and structural suitability of each bridge type for the same span was compared. Since the systemic stiffness of the CSSB can be more improved by adopting concrete girder, it was confirmed that the CSSB has advantage in securing economic efficiency, reducing deflections and the period of erection program, and increasing wind resistance.
Facing construction challenges in constructing two bridges to provide access to Singapore’s new waste facilities
Authors: Tapley Mike , Poland Jacco
Published: March 2021

Singapore faces a problem of how to deal with its waste and has consequently designated a site in the industrial area of Tuas for an incinerator and waste treatment plant. To access the site, two bridges are required to cross a waterway serving cooling water to an existing power station. This paper discusses the constraints faced in the design and construction of the bridges and how the Designer and Contractor developed innovative solutions to overcome challenges they posed.

In planning the bridges, it was essential that at no stage construction activity impacted the operation of the inlets and the associated access provisions. To meet this requirement, the bridges needed to span a clear distance of 75 m. With the aim of minimising the programme time required to construct the bridge, precast techniques were to be used extensively, with the pier heads each side of the main span being precast shells 28 m in length and the main beams being 50 m long precast U beams.
Challenges of implementing bridge model updating in industry practice
Authors: Ye Cong , Middleton Campbell , Kuok Sin-Chi , Butler Liam
Published: March 2021

Model updating aims to update an analysis model (e.g. a finite element model) of an engineering structure in order to closely represent the true condition and performance of the physical structure. Model updating of bridges has been an active research field for more than two decades, yet the confidence and practical usefulness of bridge model updating results may be subject to questioning. While model updating may have worked well for many other engineering applications, it has found to be challenging and problematic to implement such practice on bridge structures. More recently, there has been a vision of developing bridge digital twins which can automatically update the model in near real time as new monitoring data become available. This paper aims to elaborate on the critical issues that have not been addressed properly to enable real-world implementation of bridge model updating.

A series of industry facing semi-structured interviews have been conducted with 19 bridge professionals (owners, operators and consultants) to aid in investigating the technical and practical challenges of implementing bridge model updating in practice. It is envisioned that the outcomes of this paper will inform future research regarding model updating and digital twin development for bridge applications.
On the seismic vulnerability evaluation of RC bridges exposed to corrosion
Authors: Zucca Marco , Crespi Pietro , Pasqualato Giuseppe
Published: March 2021

Recently, the engineering interest about the durability of existing reinforced concrete structures has significantly increased as confirmed by the conspicuous scientific literature. The results of these studies are influencing the development of new structural codes. Among the wide range of existing reinforced concrete structures, motorway viaducts stand out for their strategic relevance. Most of these structures were built between ’60 and ’70 years and, nowadays, the materials degradation phenomena are leading to strength capacity reduction, either in serviceability condition or in presence of exceptional loads such as the seismic action. In order to evaluate the degradation phenomena effects on the seismic vulnerability of motorway viaducts, this paper shows an efficient procedure to evaluate the seismic performance of reinforced concrete bridges starting from the modelling of the materials degradation, according to several scenarios, and by carrying out multimodal pushover analyses.
Seismic performance of Greater Jakarta LRT with added lead rubber bearing using non-linear time history analysis
Authors: Imran Iswandi , Hamidah Marie , Shiddiq Husain A. , Suryadi Tri , Al-Harris Hasan , Hidayat Syamsul
Published: March 2021

In order to overcome stringent seismic requirement in the new Greater Jakarta Light Rail Transit Project, a breakthrough seismic system shall be chosen to obtain expected structural performance. This seismic system shall be designed to provide operational performance level after strong earthquake events. To achieve the criteria, seismic isolation system using Lead Rubber Bearings is chosen. With this isolation system, Greater Jakarta LRT has become the first seismically isolated infrastructure and apparently an infrastructure with the largest numbers of LRBs in one single project in Indonesia. More than 10.400 Pcs LRBs are used for the first phase of the construction and the numbers will be certainly increased in the next phase of the construction. To evaluate the structural performance, non-linear time history analysis is used. A total of 3 pair matched ground motions will be used as the input for the response history analysis. The ability of the lead rubber bearing to isolate and dissipate earthquake actions will determine its structural performance level. This will be represented by the nonlinear hysteretic curves obtained throughout the earthquake actions.
Experimental study on seismic performance of suspended ceiling components
Authors: Wang Yong , Jiang Huanjun , Wu Chen , Xu Zihui , Qin Zhiyuan
Published: March 2021

Suspended ceiling systems (SCSs) experienced severe damage during strong earthquakes that occurred in recent years. The capacity of the ceiling component is a crucial factor affecting the seismic performance of SCS. Therefore, a series of static tests on suspended ceiling components under monotonic and cyclic loadings were carried out to investigate the seismic performance of the ceiling components. The ceiling components include main tee splices, cross tee latches and peripheral attachments. All specimens were tested under axial loading. Additionally, the static tests of cross tee latches subjected to shear and bending loadings were performed due to their seismic vulnerability. The failure pattern, load-carrying ability, deformation capacity and energy dissipation of the ceiling components are presented in detail in this study.
Site controlling in infrastructure projects by digital methods
Authors: Walther Tino , Pieper Marianne , Bargstädt Hans-Joachim
Published: March 2021

The construction industry is essentially determined by digital transformation and an increasingly complex market environment. Project controlling and monitoring is of high importance for construction site activities to achieve the project goals. Digital planning and recording methods make it possible to identify deviations at an early stage and to ensure the profitability of the project. To discuss the current practice of construction performance measurement as well as digital approaches in this domain, a qualitative study was carried out. The results of this empirical analysis examine the status quo of the construction performance measurement in civil engineering companies to illustrate the currently used methods and trends. Findings for the future use of digital planning and recording methods were obtained from the investigation. Based on empirical hypotheses, recommendations for action as well as for an improved process model are given.
Modal shape identification for short and medium span bridges using wavelet based vehicular sensing approach
Authors: Jian Xudong , Sun Limin , Xia Ye
Published: March 2021

Modal parameter identification has been one of the key issues in the research of indirect bridge structural health monitoring. This paper presents a new indirect approach identifying modal parameters for short and medium span bridges, using dynamic responses of three connected vehicles. Accelerations of these vehicles are firstly subtracted to eliminate road roughness effects, so that the bridge frequency visibility in the frequency domain is improved. The wavelet analysis is performed to identify modal frequencies and shapes of bridges from the subtracted acceleration of moving vehicles. Systematic numerical experiments are performed to investigate the fidelity of the approach. Results show that the proposed approach can identify the bridge modal frequencies and shapes with promising accuracy and robustness.
Navigation clearance evaluation and marine simulations for the planning of new bridge spans
Authors: Kite Steve , Pitchforth James , Yip Sammy , Artejo Paz , Galang Gerardo Ramon
Published: March 2021

The sizing of the main span dimensions for new marine bridge crossings needs to consider the current shipping vessels using the waterways and the future growth in marine traffic. Internationally accepted guidelines are used for initial sizing of the navigation clearances, but confirmation of the safe passage of vessels requires simulations to be undertaken. For two major marine bridges planned in the Philippines the marine navigation clearance assessments have been carried out, and the results verified via realistic simulations carried out at the facilities available in the Maritime Academy of Asia and the Pacific (MAAP). This paper outlines methodology of the theoretical calculations and the simulations performed, which confirmed the clearances and informed the design of the required navigation aids.
The structural rehabilitation of the Costa e Silva bridge in Brasília, DF, Brazil
Authors: Almeida Pedro , Holanda Maruska L. S. , Almeida Ronaldo O.
Published: March 2021

The structural rehabilitation of bridges is generally motivated by the premature aging of the structures and the increased daily traffic of vehicles. In the case of the Costa e Silva Bridge, the rehabilitation was conceived by the Federal District Government due to the partial collapse of the viaduct over the “Galeria dos Estados”, occurred in February 2018, with the same age and the same structural system and due to the relevance for Brasília's transportation system. Also, it was designed by the renowned architect Oscar Niemeyer and the only one designed by him that was built. The bridge is part of the world heritage site of the "Plano Piloto" of Brasília, by UNESCO. The investigation of the structural behavior of the bridge, to verify the need for rehabilitation, was made from visual inspections, geometric and topographic surveys, photographic records, extraction of samples of concrete, analysis of the original building design and after some occurrences along the way of time, structural monitoring. As a result of these investigations, several damages were identified, in particular: cracks in the webs of the box girders, concreting failures, increased permanent overload due to the thickness of the current pavement layer, leaching of concrete and, mainly, approximately 40 cm of deflection at cantilever beams. All of these damages were simulated in the numerical model of the bridge, proving that the excessive deflection at central span is resulted in the loss of prestressing due to stress corrosion and fatigue, reducing structural stiffness and can lead to sudden collapse. As the solution for rehabilitation of the structure was designed a reinforcement with external prestressing to reduce the cracking process and to neutralize the loss of prestressing, due to strands corrosion that can result in broken wires.
Swan Street Bridge Upgrade – Widening a 70-year old bridge
Authors: Watson Alistair , Paton Scott , Cowell Andrew
Published: March 2021

The Swan Street Bridge is a reinforced concrete five-span arch bridge crossing the Yarra River in Melbourne, Australia. Constructed circa 1950, it provided four lanes of traffic and narrow pedestrian footpaths on both sides. The bridge forms part of a key route for vehicular access into the Central Business District, as well as pedestrian thoroughfare to the sporting and events precinct.

Substantial increases in traffic volumes meant the bridge had become a significant bottleneck and was hazardous for pedestrians. In response to this, a scheme was developed to widen the bridge – providing an additional lane of traffic and four-metre-wide Shared User Paths on both sides – all guided by an overlaying architectural vision created by the winner of a design competition.

This paper presents the structural technical solutions adopted for the strengthening and widening, which considered the original structural design, as well as the architectural intent for the widening.
Rehabilitation of bearings of a major earthquake damaged railway bridge
Authors: Wessel Ronald , Brown Geoff , Harris Morgan , Kotzé Rudolph
Published: March 2021

The Clarence River Rail Bridge is a 478 m long steel truss girder bridge located 40 Km north of Kaikoura. The cast iron fixed and guided pinned bearings of the bridge suffered significant damage during the November 2016 Kaikoura Earthquake, likely caused by vertical seismic accelerations in excess of 1g.

Replacement of the damaged cast iron guided pinned bearings involved the design of new bespoke pinned steel bearings with modern stainless steel and approved sliding material (ASM) surfaces newly introduced to AS5100.4:2017.

The use of modern bearing materials and established detailing principles have led to rehabilitating an earthquake damaged 80-year-old bridge with design and construction of the earthquake repairs completed in less than 12 months.
Aerodynamic behavior of wind turbines with polygonal cross- sectional tower
Authors: Kim Yong Chul , Tamura Yukio
Published: March 2021

Wind turbines are commonly used power generation systems around the world and their application is becoming increasingly widespread. Traditionally, circular‐cross‐section wind towers have been used, but recent upsizing of wind turbines has exposed weaknesses of these structures, including problems related to manufacturing and inadequate strength. Thus, the concept of site‐ assembled modular towers with polygonal cross‐sections such as octagonal and/or tetradecagonal has been proposed, but their wind‐resistant performances have not been clearly investigated. In the present study, the wind‐resistant performances of polygonal cross‐sectional towers were investigated through wind tunnel tests. It was thus found that the maximum force coefficient of the upper structure is larger than that of the tower, which makes the effect of cross‐sectional tower shape rather small. The mean and fluctuating lift force coefficients of a helical square cross‐sectional tower were quite small for cases of tower only and wind turbine.
Experimental fire performance of unloaded stay-cables for bridge infrastructure
Authors: Nicoletta Benjamin , Gales John , Kotsovinos Panagiotis
Published: March 2021

The performance-based fire protection design of cable-supported bridge structures is becoming more common as stakeholders desire more resilient infrastructure. Currently, there exist significant knowledge gaps regarding the fire performance of structural steel cables. The study herein examines the thermal response of several varieties of unloaded steel-stay cables during exposure to a non- standard methanol pool fire. Eight stay-cables varying in configuration (locked and spiral coil), diameter (22,6 mm – 140 mm), and alloy (stainless and galvanized steel) are supported above a 0,6 m x 0,48 m methanol pool fire for duration of approximately 35 minutes. Thermocouples are instrumented at the top, core, and soffit of the cable structure at four different cross-sections to monitor heat transfer during and post-fire. Digital image correlation (DIC) is applied in conjunction with narrow-spectrum illumination to monitor the cable surface without optical interference from flames. Global and individual wire strains are calculated from the DIC analysis to quantify thermal expansion. Temperature data throughout the cable structure presents insight into the heat transfer of steel wire-rope elements. Preliminary results indicate individual wire thermal expansion is similar to that of the global cable structure and that interaction between adjacent wires may limit individual wire expansion. This implies thermal expansion may not be consistent until the cable cross-section is of uniform temperature.
The York-Arup cable experiments: Implications for the fire design of cable-supported bridges
Authors: Nicoletta Benjamin , Gales John , Kotsovinos Panagiotis
Published: March 2021

Recent trends towards performance-based fire designs for complex and critical structures have posed questions about the fire resilience of bridge infrastructure. There are little-to-no code requirements for bridge fire resistance and practitioner guidance on the subject is limited. Research on the fire performance of cable-supported bridge structures is scarce and knowledge gaps persist that inhibit more informed fire protection designs in a variety of bridge types. There have been few numerical or experimental studies that investigate the fire performance of steel stay-cables for use in cable-supported bridges. The thermal response of these members is critical as cable systems are highly dependent on the response of individual members, such as in the case of an anchor cable for example. The study herein examines the thermal response of several varieties of unloaded steel- stay cable during exposure to a non-standard methanol pool fire and the implications for the structural response of a cable-supported bridge. Experimental thermal strain data from fire tests of various stay-cables is used to inform high-level insights for the global response of a cable-supported bridge. Namely, the effects of cable thermal expansion on the overall cable system is approximated.
Analytical study on evaluation of residual strength for steel-concrete composite girder bridge after fire
Authors: Takahashi Yusuke , Imagawa Yusuke , Ohyama Osamu
Published: March 2021

Fire damage to bridges occurs frequently in Japan and in other countries. Previous bridge fire accidents suggest that it is important to understand the structural performance of the bridges after their exposure to fire. The authors have studied the evaluation of the stress of the steel- concrete composite girder bridges as a simply supported bridge damaged by fire. First of all, fire test was carried out to clarify the temperature distribution of the composite girder and a static loading tests before and after fire were conducted to confirm the effect of the reduction of rigidity from fire. Next, numerical analysis was carried out to indicate the stress distribution and deflection on the composite girder bridge from live load after fire.
Innovation & Fast Track Construction
Authors: Roy B. C. , Guha Tanmoy , Ekambaram R.
Published: March 2021

Issue of mobility is of the greatest concern across the world and is based on end-user requirement. Fast track implementation and innovative schemes are required. Transport innovation can be categorized as

Innovations for developing Infrastructure

Innovations for developing vehicular systems

Projects including different urban context require innovative design/construction technique specific to site requirement and improve mobility. The paper deals with innovative design to reduce cost and time and focuses on technology and knowledge fusions. Use of steel-concrete superstructure has now become de rigueur as highly automated fabrication and transport logistics have improved throughout India. Precast segmental construction has been shown to be not only for glamorous and highly visible urban projects such as flyovers, but also for pedestrian subways, that would go typically unnoticed. Only the innovator knows how the innovation came to be that serves the society by reducing implementation duration and allows greater surface mobility. These are some of the items that are described in this paper.

It also focuses on innovations that include fast track implementation in transportation sector for infrastructure and with a brief on system. Case study/studies are presented to discuss concept, design and construction in improving Indian urban mobility.
Wind turbine structures – recent developments regarding fatigue design
Authors: Rauch Marion , Knobloch Markus
Published: March 2021

Wind energy is already significant among the renewable energies and will become even more important in future. The development of wind turbines with heights between 100 m and 160 m provides new challenges for tower structures. The towers are usually made of steel. However, hybrid towers are also common for high towers. This paper gives a brief overview on the current situation of the wind energy market and the consequent challenges for wind turbines towers. Then, the concepts of steel and hybrid towers are presented as well as typical design guidelines of wind turbines with the focus on recent developments. The paper focuses on the challenges and possible innovative solutions concerning the fatigue verification of towers made of steel. In particular, attention is paid on the recent developments regarding the influence of the size effect as well as thickness transition of thick plates of the fatigue verification.
A visual integration information platform for maintenance management of concrete structures based on information technology
Authors: Zhang Y. F. , Yokota H. , Miao P. Y.
Published: March 2021

Maintenance management of concrete structures is often complicated because a large amount of information is generated during the service time. The lack of links between information storage and spatial locations increases the difficulty in information retrieval and display. A large number of information technologies provide the possibility of efficient information management during the maintenance management phase, such as building information modeling (BIM) technology providing digital geometric spatial information of concrete structures, geographic information system (GIS) technology providing geospatial information, and databases providing information storage. This paper proposes a visual integration information platform for maintenance management of concrete structures which enables the storing, retrieving and extracting of maintenance information more effectively through linking documents with 3D visual objects.
Development of an innovative one part green concrete
Authors: Tsioulou Ourania , Lampropoulos Andreas , Neocleous Kyriacos , Kyriakides Nicholas , Polydorou Thomaida
Published: March 2021

Concrete is one of the most commonly used construction materials. However, the main drawbacks in the use of concrete are related to the use of cement and subsequently the high percentage of carbon dioxide emissions. The use of cement substitutes is an area where there is a lot of ongoing research. Geopolymer concrete is a concrete in which cement is replaced by waste materials such as Pulverised Fuel Ash (PFA), or Ground Granulated Blast furnace Slag (GGBS). To activate the geopolymerisation, an alkali activator is used. The procedure, which is used for the production of a geopolymer concrete, is normally a two-part procedure: Preparation of the alkali activator one day before the mixing and mixing of the aluminosilicate sources (PFA, GGBS) with the activator. To make the production of geopolymers more user friendly it needs to be converted to one part procedure where water will be added in a readymade mix. In the published literature, there is research on one- part geopolymers, but there are limited studies on the use of demolition waste materials as substitution of PFA and GGBS in this type of materials. With the current study, different sources of raw materials focusing on demolition waste materials such as red bricks and reclaimed concrete, which are commonly used in construction worldwide, will be examined for the production of one- part geopolymer. The major aim of this research proposal is to develop an innovative sustainable one-part cement free geopolymer concrete. The new concrete is a “green” concrete where cement is replaced by waste materials. Construction demolition materials such as red bricks can be used as raw materials in the geopolymer matrix. This project will focus on the selection, characterisation and development of the appropriate processing of these red bricks so as they can be used as raw materials in the geopolymer matrix. Also, the development of one part mix where the new concrete will be ready for use by adding only water in it, is another aim of the proposed project.
Meso-scale study of notched and un-notched plain concrete beam under three-point bending
Authors: Pal Biswajit , Ramaswamy Ananth
Published: March 2021

In this study, meso-scale (mm-cm scale) modelling approach is adopted to simulate the behaviour of plain concrete beam under 3-point bending. At meso-level, concrete is assumed as either a two- phase or a three-phase composite material (mortar, aggregate and/or interfacial transition zone- ITZ). In this tudy, first the aggregates are generated and placed in the concrete domain with prescribed randomness. The remaining space in the concrete domain is then filled with mortar. However, in three phase model, ITZ of finite thickness surrounding the aggregates is assumed to exist. In this study, three geometrically similar beam specimens with and without notch have been considered. The simulated load-crack mouth opening displacement (CMOD) is then validated with the corresponding experimental data. A convergence study of peak load with different specimens in terms of randomness in aggregates generation and placement has been studied.
Degradation modelling of railway infrastructure
Authors: Laskowska Ewa , Vatn Jørn
Published: March 2021

In this paper the Wiener process with linear drift is proposed as a degradation model for the railway substructure. The model is based on the empirical data describing loss of tracks quality over the distance of one kilometre. The impact of explanatory variables on tracks degradation is investigated. The Bayesian framework is applied to examine uncertainty in the development of degradation for different sections along the tracks.
Large-scale fatigue tests on prestressed concrete beams
Authors: Birkner Dennis , Marx Steffen
Published: March 2021

For a better estimation of the fatigue lifetime of real structures, tests on large-scale beam specimens are more suitable than on common cylindrical specimens, since effects like local stiffness changes and stress redistributions can be reproduced more realistically. This article presents an experimental setup for large-scale concrete beams subjected to fatigue loading. Additionally, the fatigue tests are simulated with a numerical model. The results of the numerical analysis show a successively increasing damage propagating from the edge into the inner part of the cross-section in the mid span with increasing number of cycles. This results in stress redistributions which extend the lifetime of the structure. The evaluation of the experimental investigation on the first beam specimen shows a larger stiffness degradation at the upper edge than in the centre of the cross-section as well as increasing strains at this location. This matches the expected effects from the numerical analysis.
Verification of applicability of weathering steel based on long-term exposure tests in Vietnam
Authors: Miura Shinichi , Tung Dang Dang , Iwasaki Eiji
Published: March 2021

Under the appropriate corrosion environment, weathering steel does not require paint, so it has reduced life cycle costs when compared to conventional steel. The applicability of weathering steel has been systematically investigated in countries like Japan and the United States of America. However, in Vietnam, the influence of environmental factors on corrosion behaviour and the applicability of weathering steel has been evaluated by short-term exposure tests. In this study, we performed long-term exposure tests in Vietnam to clarify the time-dependent changes of corrosion behaviour and to verify the applicability of weathering steel. The time-dependent changes of corrosion loss were dependent on the corrosion environment. The corrosion rate greatly increased in areas with high relative humidity. Weathering steel is applicable in various regions in Vietnam, but it should be applied carefully in areas with high relative humidity.
Corrosion risk assessment for sheet piles in road environment – using ISO9223 dose response function and long term exposure samples
Authors: Gedge Graham , Frydman Bruna
Published: March 2021

Road side environments exposed to de-icing salts do not readily fall within any of the qualitative assessment categories commonly used in ISO 9223 to define corrosion risk. The potential impact of seasonal use of de-icing salts complicates the definition of the environment and may increase corrosion rates. It is therefore common within highways authorities to assume the environment is comparable to a marine splash zone, C5 environment of ISO 9223, equating to a high corrosion loss for 120-year design life. In the absence of data this may be an understandable, if conservative, assumption. This paper challenges this assumption and presents a detailed case study for sheet piling adjacent to highways, exploring the benefits of a quantitative assessment using the Dose Response Function methodology given in ISO 9223 and calculation of long-term loss in accordance with ISO 9224. The method allows better definition of the service environment and results in more modest assessment of total corrosion loss. The assessed corrosion loss from this methodology is compared with the results obtained from the recovery and analysis of long-term exposure samples from the English trunk road network. The range of total corrosion loss of the mild steel samples recovered, fall within the range predicted by the analysis using the methodology described in ISO 9223 and ISO 9224 over the exposure period.
Resource consumption in construction as a global challenge
Authors: Lieboldt Matthias , Seifert Wiebke , Tietze Matthias
Published: March 2021

The construction industry plays a central role in the design of our environment. Global population growth is associated with an increase in material resource consumption and CO2 emissions. Sustainable ideas and developments to reduce the need for resources and CO2 emissions as well as to increase the service life of buildings are becoming more important. Carbon Concrete Composite – C³ is made of a high-tensile reinforcement with carbon fibers and concrete is particularly convincing due to its high durability and long service life. In practice, its suitability has already been proven in numerous projects, so that carbon reinforced concrete is an integral part of research and application. The selected example illustrates the potential of carbon concrete construction. For this purpose, a material-related and systemic comparison of steel and carbon reinforced concrete is carried out using the example of a carbon reinforced concrete bridge.
Experimental study on mechanical behavior of combined joint using adhesives and high strength bolts
Authors: Kamino Takuya , Fujimoto Takashi , Yamaguchi Takashi , Aoki Yasumoto , Akamatsu Shinsuke , Horii Hisakazu
Published: March 2021

As a repair for corrosion damage of a steel bridge, a patch plate-repair using high strength bolts is generally applied. This method requires the surface of the damaged corroded part filled with an epoxy adhesive flat. The load transferring mechanism and slip resistance of such a combined joint with adhesives and high strength frictional bolts aren't clear. Since the shear strength of an adhesive might be increased due to constraint by the bolt axial force, the combined joint's slip resistance would be increased. To clarify the mechanical properties of the combined joint and to propose a new design method for such joints, two experiments have been conducted. The first was a frictional force experiment for adhesive specimens subjected to contact pressure on the surface to evaluate the constraint effect of adhesive on shear strength quantitatively. The last one is a slippage experiment for the combined joints to evaluate its slip coefficient.
Push-out tests of shear connectors for new fully assembled steel-concrete composite beams
Authors: Hou Hetao , Wang Ning , Zang Zengyun
Published: March 2021

To accomplish rapid installation and replaceability, a new type of connector for new fully assembled steel-concrete composite beams was studied. The connectors are fixed on the C-shaped channels of the prefabricated floor slab. The load transfer along the interface of the precast floor slab and the steel beam is primarily achieved through the friction between the beam flange and the channels. Push-out tests were conducted to study the mechanical properties of new composite beam. The effects of different C-shaped channel types, repeated loading and number of connectors were investigated. Test results showed that all the connectors exhibited satisfactory performance. When the section height of C-shaped channel is small, the restraining effect on the connector is more remarkable. The shear strength and shear stiffness of the connectors can be improved by reloading. The formulas for calculating the shear strength derived agree well with the experimental results.
A structural analysis: Designing our way into sustainability
Authors: Frisk Lis
Published: March 2021

With the average global temperature on the rise sustainable solutions are needed to combat climate change. The Paris Agreement was created to keep the average global temperature below a 2°C increase from pre-industrial levels. New Zealand, signatory to the Paris Agreement, has new legislation on a Zero Carbon Amendment Act to reduce all emissions to net carbon zero by 2050. 20% of all carbon emissions in New Zealand, half derived from construction and materials (embodied carbon), are from buildings.

The New Zealand Green Building Council (NZGBC) published a Zero Carbon Road Map to achieve the 2050 goal, including reducing embodied carbon 20% by 2025. Considering the structure alone, using sustainable materials can be challenging to apply to a project due to industry standards and code requirements. One method, discussed in this paper, can be implemented immediately, which is to study how different framing methods affect the amount of embodied carbon in the superstructure and substructure for a potential reduction of up to 20%.
Sustainable practices for bridge structures
Authors: Singh Harminder
Published: March 2021

On a typical project, the sustainability requirements of bridges should be considered from the planning stage or earlier. In recent years, a lot of research has been undertaken to improve the durability of reinforced concrete and with the use of high-grade steel and weathering steel, the sustainability aspects of bridges have significantly improved. To ensure sustainability in bridges, the already available framework of sustainability covering environmental, economic and social aspects can be implemented. There are several other frameworks and guidelines available from different countries about the sustainability requirements that can be useful for bridges. The paper presents a brief overview of sustainability in bridges, current practices and areas of emerging and future opportunities to improve sustainability.
Performance-based methodology for seismic assessment of code- conforming RC buildings
Authors: Murari Krishna , Singh Harvinder , Takkar Savleen
Published: March 2021

The current Indian code for seismic design of structures is based on the force-based design (FBD) philosophy but the damage is more related to strain and displacement rather than strength. Also, structures can’t be designed for target design objectives by FBD method under a specified hazard level. Hence it became necessary to develop new codes and standards based on more robust design methodology to overcome the various shortcomings. The paper presents the results of a study conducted to evaluate the effect of provisions mandated by BIS design guidelines on the performance of a multi-storeyed building in event of a seismic activity. The performance of the building was evaluated on the parameters given in the FEMA guidelines. It was observed that the RC buildings designed as per Indian standard is found to be under-utilized and its overstrength ratio is observed to be of order two, leading to uneconomical design as compared to the building designed according to Performance based methodology for achieving a similar value of the performance level.
Load effects of overweight and oversize vehicle traffic on pavements and bridges
Authors: Hwang Eui-seung , Hwang Min-Tae , Kim Do-Young , Kim Seong-Min
Published: March 2021

Currently vehicle traffic regulations regarding on axle and total weights in Korea are simple, outdated and different from the regulations in other countries, such as US or European countries. In this study, load effect of over-loaded and special permit vehicle traffic on bridges and pavements are analyzed. Types of typical bridges include concrete and steel girder bridges. Types of pavements include asphalt and cement concrete pavements. Various weigh-in-motion (WIM) truck data are collected and used for comparing overweight ratios. Based on WIM truck data, load effects of various oversize vehicles mixed with common traffic are analyzed for various bridge types. Oversize vehicles include vehicles used in construction field, crane vehicles and transport vehicles for the military purpose. The effect of axle types on pavement design is also analyzed. The results of this study will be the basis of new provisions and regulations regarding on axle and total weights limitations as well as special permit vehicle.
Proposal to transform "AS(AS/NZS) 5100 Bridge Design Standard" to "AS/NZS 5100 Bridge and Transport Infrastructure Design Standard"
Authors: Pritchard Ross
Published: March 2021

The 2017 AS(AS/NZS) 5100Bridge DesignSeries is an evolution of former road authority and (heavy) rail authority standards that can trace their initial roots to 1960s. Originally written in an era when all bridges were owned by public organizations. The 21st century has both public and private ownership of bridges. The scope of transport infrastructure has also expanded and now includes managed motorway gantries, noise barriers and large sign structures

This paper has identified an inconsistent approach to scope. It proposes a new wider scope of transport infrastructures to be included in the standard. This consistency in approach will remove inconsistent treatment of non-bridge structures relating to fatigue and load combinations in the current standard. The paper has also identified that high frequency metropolitan trains has resulted in fatigue cycles being grossly underestimated.

The paper proposes a name change from bridge to transport infrastructure design to fully capture the scope of the changes.
Nonlinear models for design of circular RC columns under ultimate and service states
Authors: Barros Helena , Ferreira Carla , Figueiras Joaquim , Pimentel Mário
Published: March 2021

The present paper is dedicated to the ultimate and to the service design of circular reinforced concrete sections under axial load and bending moment, according to Eurocode 2 [1].

The objective of the present work is to develop design equations for circular reinforced concrete sections, solving the equilibrium equations by mathematic symbolic software. The concrete only supports compressive stresses and the steel can hold both tension and compression. The nonlinear equation of EC2 [1] is used for compressed concrete in the ultimate design. The steel is considered to have a linear elastic constitutive law up to the yield stress, followed by a plastic behaviour. The ultimate design condition is posed in terms of maximum strains for the most compressed concrete fibre or for the tensioned steel bar, permitting the definition of interaction abacuses, shown in the present paper.