bluuebunny/crossref_metadata_2025 huggingface dataset:
First Environmental Product Declaration, EPD, for a Building
Authors: Wiklund Ulf Kjell Christer
Published: February 2021

Tyréns has together with Folkhem developed the first Environmental Product Declarations, EPD, for an entire building in the International EPD system. The environmental declaration is based on the rules PCR 2014: 02 Buildings, version 1.0, where Ulf Wiklund, Tyréns, also is international PCR coordinator.

The developed EPD applies to a concept house "apartment buildings in solid wood above ground" and consists 10 floors. The bottom level and half 2nd floor below ground is built in concrete, while the other floors above ground and constructed mainly with the Crosslaminated timber. Folkhem has taken a strategic decision to always build the house where solid wood is the most important and largest constituent. Build pieces of wood coming from Folkhems partners Martinson, who specializes in building solutions in cross-laminated timber.

If a life cycle analysis, LCA, will constitute the basis for an Environmental Product Declaration (EPD) it requires a joint policy document that sets the framework for how the whole of the industry concerned should develop their environmental declarations, called a PCR (product-specific rules). The life cycle analysis is carried out in accordance with the product-specific rules for buildings, PCR UN CPC 531 Buildings (PCR 2014: 02 Buildings, Version 1.0), published by the International EPD system and requirement several steeringdocuments/frameworks and international standards. PCR UN CPC 531 Buildings in turn, is based on a series of standards and frameworks.

One goal of the EPD is that it will help to reduce the climate impact from the construction sector. Urbanization means that there is a great need to build more while the building industry accounts for a significant load on the environment and climate. To support wise choices have environmental impacts throughout their life cycle is taken into account. Next major development and innovation efforts is to create tools that make it possible for "a broader mass" of developers, planners, designers to use LCA calculations in planning and design.
Implementation and cost-efficiency of stainless steel bridge edge beams
Authors: Veganzones Muñoz José Javier , Sederholm Bror
Published: February 2021

Bridge edge beams may take up to 60% of the life-cycle measure costs of a bridge and cause con- siderable user costs because of roadworks. The Swedish Transport Administration presented new edge beam solutions that could become better for the society in terms of cost. Stainless steel has been considered for enhanced durability, preventing expensive maintenance. The purpose of this paper is to motivate the use of stainless steel in the solutions proposed. A life-cycle cost analysis is carried out to evaluate the cost-efficiency of a concrete integrated edge beam with stainless and carbon steel reinforcement in a bridge project. The influence of the discount rate is addressed by a sensitivity analysis. Stainless steel is shown to lead to cost-efficient edge beam solutions. Low dis- count rates encourage using better quality designs with higher investment costs but lower life- cycle measure costs and user costs, which supports the use of stainless steel.
Maintenance and repair of slab anchors on a curved non composite steel box-girder bridge
Authors: Konno Koji , Nagata Yoshifumi , Itabashi Yumiko
Published: February 2021

Fractures of slab anchors were detected on a curved non-composite steel box-girder bridge on the Metropolitan Expressway. Fractographic investigation concluded that the fractures were caused by metallic fatigue. Because of fractures of slab anchors, a gap originated due to bond deterioration around the boundaries of the RC slab and the steel girder, and also closure behavior of the gaps due to traffic of over-sized vehicles was confirmed. Maintenance and repair was implemented to integrate once again the RC slab and the steel girder. As means of construction, post-installed anchor was used since traffic regulation is unnecessary and construction is possible from beneath the road surface.

Therefore, a FEM analysis and a local load carrying test was carried out intended for curved box girders of a maximum transverse slope of 9%. Reviews considering deformation behavior and acting force of the damage were conducted and was reflected in the repair design.
Contributing human and organizational factors for the collapse of a temporary supporting structure for the B-tower in Rotterdam
Authors: Terwel Karel
Published: February 2021

In October 2010 the 70m high B-tower was being erected in the city centre of Rotterdam. The floors of the first five storeys were made as reinforced wide-slab floors. For the temporary support of the precast planks during casting of the concrete scaffolding was used. In the floor plan a void was foreseen, resulting in an increased storey height. At this position the scaffolding had a height of approximately 11.50m. During casting of the floor, the temporary structure collapsed, resulting in 5 injuries among the construction workers.

Investigation from the Dutch Safety Board revealed that a large number of stability braces was omitted in one direction, resulting in instability and collapse of the temporary structure. This omission had been noticed, but because of unclarity in responsibilities no follow up was given to this warning.

This paper describes the structure of the temporary scaffolding, will reveal the technical cause and will pay attention to underlying human and organizational factors that contributed to the failure of this structure. For these contributing factors a theoretical framework with potential influencing factors for structural safety is used.
The architectural and structural revitalization of an old cement plant in the south of Poland
Authors: Rawska-Skotniczny Anna , Tylek Izabela , Nalepka Marek
Published: February 2021

This paper presents the history and two consecutive reconstruction programs of a large former cement plant for adaptive reuse. The cement plant was originally constructed in the beginning of the 20th century in Opole, Southern Poland. At the end of World War II the production facilities of the plant were completely devastated and the equipment was removed by the occupying Russian Red Army. In 1948 they were reconstructed for adaptive reuse as grain storage facilities. Following the reconstruction the buildings were again not used for many years. Post-war reconstruction works, carried out to meet the short-term needs, led to numerous damages and to the obliteration of the architectural features and a significant loss of structural integrity. Later on the buildings were purchased in a ruined state by a private investor, who gradually transformed them into a commercial exhibition centre, known as "domEXPO".
Multi-level road bridge assessment
Authors: Skokandić Dominik , Mandić Ivanković Ana , Dzeba Ivica
Published: February 2021

Multi-level assessment procedure to evaluate safety/reliability of existing road bridges is elaborated in this paper. Implementation of available WIM measurements is described in more detail, while Bayesian update is foresight as a future research step. Proposed assessment method will be evaluated through its application for short to medium span reinforced concrete slab bridges in Croatia and in this paper, the first case study is presented.
Challenges in seismic design of incrementally launched bridges of Northern Marmara Motorway
Authors: Combescure Etienne , de Courcelles Charles , Ghavamian Shahrokh
Published: February 2021

This paper presents the challenges in the seismic design of the incrementally launched bridges of the Northern Marmara Motorway project in Istanbul Turkey. First it describes the initial design for these viaducts, then it presents the alternative design based on incremental launching method (ILM) and finally does a comparison of their performances. Regarding the earthquake resistance studies, traditional multimodal response spectrum analysis was carried out. This was then completed by a nonlinear time history analysis considering the behaviour the fluid viscous dampers, the cracking of concrete and steel rebar yielding at the plastic hinges. The results of these two analyses are compared in terms of forces and displacements, indicating the conservatism of the modal spectral analysis.
Lima Convention Centre: a singular seismic resistant building structure
Authors: Bernebéu Larena Alejandro , Gómez Mateo Javier , Álvarez de Tomás Javier , Fernández Usón Tono , Ríos Raúl
Published: February 2021

Recently opened in October 2015 for the World Bank and International Monetary Fund meeting, the Lima Convention Centre (LCC) is a major milestone in South American construction. The building presents a great architectural and structural singularity, and was designed and completed in just one and a half years.

LCC has a rectangular shape in plan, with dimensions of 100 x 60 meters, and a total height of around 45 metres above ground. The building required several column-free large spaces, to meet the demands of its use (large meeting rooms and exhibition areas, with the main one located at an upper level and occupying almost the entire floorplate) and its architectural intention, including a large opening that houses an open-air terrace hall. The structure has therefore to accommodate spans of more than 40 metres. In addition, being located in a highly seismic area, the building is subject to significant horizontal forces.

The main seismic resistant structure is formed by a very rigid structural macro-system, composed of four big concrete cores and a large steel truss that goes all around the main meeting hall at the upper level. The steel trusses are rigidly connected to the concrete cores, strategically placed close to the corners, creating a system of huge rigid frames in both directions, which provides horizontal stability. This macro-system is complemented by a set of smaller rigid frames located at every level, which contributes to distribute and control horizontal stresses and displacements.

The structure combines prefabricated concrete elements below ground and a composite steel- concrete structure above ground, and despite its apparent irregularity and its large openings and extensive spans, responds efficiently to structural and seismic requirements, while enhancing its architectural intentions.
Optimal Placement of Mega-Brace Dampers for Integrated Seismic Design of Super Tall Building Structures
Authors: Zhao Xin , Han XiaoDan
Published: February 2021

Super tall buildings are commonly controlled by earthquake in high seismicity area. Viscous dampers have been widely applied in seismic design of tall buildings to mitigate the seismic responses of super tall buildings. The energy dissipation capacity of viscous damper system is highly related to the damper configuration. Mega-brace damper system is one of the deformation amplification configurations, which can amplify the story deformation under earthquake. The mega braces can be flexibly arranged according to the building brace configuration. The installation of mega-brace dampers will cause the stiffness loss of primitive stiff mega braces. The optimal placement of mega-brace dampers will comprehensively consider the maximizing of energy dissipation capacity and the minimizing of stiffness reduction. This paper proposes an optimal placement method of mega-brace dampers which can satisfy both requirements. A real super tall building project will be employed to illustrate the applicability and effectiveness of the proposed optimal placement method for the mega-brace dampers.
Seismic horizontal forces exerted by granular material on flat bottom silos: experimental and analytical results
Authors: Pieraccini Luca , Palermo Michele , Silvestri Stefano , Gasparini Giada , Trombetti Tomaso
Published: February 2021

Seismic response of grain-silos still presents strong uncertainties and open issues. For this reason, seismic design of silos is not yet consolidated as the design in static conditions (filling and discharging scenarios) and current design codes tend to provide too conservative formulations for the estimation of the seismic actions induced by the stored material.

Experimental tests have been conducted during the last decades, including shaking table tests on scaled models for better understand the coupled behaviour of grain-silos. Recently, the authors proposed a theory for the evaluation of the horizontal seismic forces exerted by granular material on silos. The main purpose of the present study is to provide a set of simplified code-like formula for the evaluation of the seismic horizontal forces acting on the silo wall and to compare them with the results of experimental shaking-table tests and with the actual code provisions.
Spatially variable seismic ground motions and their effect on cable-stayed bridges: The role of the tower.
Authors: Efthymiou Eleftheria Anthi , Camara Alfredo
Published: February 2021

This paper focuses on the effect of the spatial variability of the ground motion on the towers of cable-stayed bridges with typical span lengths equal to 200, 400 and 600m. For this work, seismic analysis of the considered bridges is performed, accounting for the different components of the spatial variability namely: incoherence effect and wave passage effect. The response of the towers is examined under various wave propagation velocities. Finally, the discussion is extended to the effect of the angle of incidence of the seismic waves with respect to the axis of the bridge, presenting an extensive study on the seismic demand of the towers.
Development of High Penetration Agent and its Application to Concrete Bridge Deck Waterproofing, Repair and Reinforcement
Authors: Kaba Kazuya , Nagata Yoshifumi , Hiraoka Tomio , Gyakushi Hidetoshi , Ishigaki Tsutomu
Published: February 2021

This paper presents the newly developed high penetration agent for use in waterproofing, repair and reinforcement of deteriorated concrete bridge decks, which are mainly caused by fatigue cracking and penetration of water into the crack. Comparing to the ordinary permeable agent, the high permeability agent has a relatively low viscosity at low atmospheric temperature, hence, it can fully penetrate into small cracks even in cold season. Moreover, the flexural stiffness of deteriorated concrete bridge deck could be increased at approximately 25%, indicating that the high penetration agent can be applied not only for waterproofing but also for repair and reinforcement work. Recently, the high permeability agent has been widely adopted together with the asphalt waterproofing membrane (two-coat waterproofing system) in the actual maintenance work of concrete bridge deck in the Metropolitan Expressway and other highway bridges in Japan.
A refined model of concrete carbonation by coupling of multi-factors
Authors: Ge Yuanfei , Yu Shaojun , Yu Zhang , Tu Yongming , Ohlsson Ulf
Published: February 2021

Studies on carbonation of concrete play an important role in accurately predicting the service life. However, most research work on carbonation of concrete was carried out in qualitative ways and seldom in quantitative ways. In this paper, based on conservation of mass of C3S(s), C2S(s), CSH(s), CH(s), CH(aq), CO2(aq) and CO2(g) and one-dimensional diffusion and reaction equation, a refined mathematical model of concrete carbonation composed of a series of partial differential equations (PDEs) was built. Corresponding MATLAB codes were developed with calculus of differences to solve the mathematical model of concrete carbonation.

The results of the mathematical models in this paper agree very well with measurements, which show that this model can be used to accurately predict concrete carbonation as well as remaining service life of concrete bridges and other concrete structures.
Evaluation of service life design assessment according to different chloride diffusion and carbonation models applied on Belgian concrete mixtures
Authors: de Winter Liesbet , Minne Peter , Caspeele Robby , De Schutter Geert
Published: February 2021

This contribution presents the preliminary research outcomes of a pilot program for the validation of models and test methods for assessment of the durability related to Belgian concrete mixtures. The chloride diffusion and carbonation model offibbulletin 34 [1] and the recent outcomes reported infibbulletin 76 [2] are applied and evaluated. A sensitivity analysis is performed for both damage mechanisms. In addition there are certain parameters in the models which can be recalibrated to the Belgian concrete compositions or exposure conditions. Such a calibration will be performed for the common used types of cement in Belgium (CEM I, CEM III/A and CEM III/B). Preliminary research shows that for chloride ingress, the ageing exponent α, the diffusion- and migration coefficient Da(t) and DRCM,0(t0) can be recalibrated according to the Belgian situation. In case of carbonation the relationship between the natural RNAC-1 and accelerated RACC-1 inverse carbonation resistance can be determined.
Application of FRP Materials for Construction of Culvert Bridges
Authors: Haghani Reza , Yang Jincheng
Published: February 2021

Steel culvert bridges have been used for almost a century. The attractiveness of this type of bridges is usually attributed to their low initial investment, fast manufacture and installation, and their geometrical adaptability. Despite the advantages offered by steel culverts, they might suffer from a number of drawbacks in certain conditions, for instance, in case they are in direct contact with water. The most common problems are corrosion and abrasion of galvanized steel coating and fatigue. Fiber reinforced polymer (FRP) materials offer advantages such as very high specific strength and stiffness, very good durability and fatigue resistance, and light weight. Therefore, there has been a great deal of interest in using FRP composites in construction industry in the past decade. This paper presents the results of a study on feasibility of using FRP composite materials for manufacture of culvert bridges as an alternative for steel. Different aspects such as design of FRP culverts, manufacturing issues and life cycle costs are discussed.
KuBAaI - Bocholt (Germany) – Design of a GFRP footbridge as part of an urban development
Authors: Hübner Sarah , Baumann Katrin , Thie Edwin
Published: February 2021

This paper describes the structure of a weathering steel footbridge with a GFRP deck, as part of a larger redevelopment of a former industrial area in the City of Bocholt - KuBAaI.

In the recent past, the requirements on the design of footbridges regarding economic design in combination with architecture, especially in urban developments with limited budget of local authorities have increased. It is the challenge of the engineering process to explore fitting solutions to meet these requirements.

The footbridge in the KubAaI follows the chosen design concept of a low maintenance bridge by the use of appropriate materials, such as weathering steel for the main steel structure and GFRP elements for the bridge deck, and an aesthetically pleasing appearance. The structure will blend into the industrial surroundings and be much more than a mere connection, it is also a public space.
GFRP connectors in textile reinforced concrete sandwich elements
Authors: Williams Portal Natalie , Zandi Kamyab , Malaga Katarina , Wlasak Lech
Published: February 2021

In this paper, both experimental and numerical methods are presented to gain an understanding of the structural behaviour related to a TRC sandwich panel with a glass fibre reinforced polymer (GFRP) plate connection system. Double shear tests were conducted on component-scale sandwich panels to characterize the available shear capacity provided by the connectors and panel configuration. Three-dimension (3D) non-linear Finite Element Analysis (NLFEA) was applied to develop a model for the design of TRC sandwich panels while focusing on the connectors. The experimental outcome of the shear tests was applied to validate the corresponding numerical model developed in this work. The need for further modifications to the design of the shear connectors or other parameters such as panel thickness can be established accordingly. This developed FE model can essentially be applied as a design tool to further predict the structural behaviour of the full-scale sandwich elements.
Study on conceptual design process of bridges
Authors: Li Ying , Xiao Rucheng , Sun Bin
Published: February 2021

Conceptual design is the soul of the overall project design. This paper lists three main types of factors affecting conceptual design including objects, subjects and carriers. The conceptual design process is composed of three parts, namely, conception and orientation process, externalization of structural form process and technical inspection process. This paper explains the realization of conceptual design process with the conceptual design of a wide city bridge. The paper introduces the selection of structural system and structural form, general layout, determinations about the size of structural members and constructional measures, conceptual estimation of the bridge structure and initial formulation of construction schemes.
In-plane Shear Test of Floor Structure Adapting for the CSTS Using a Cross Laminated Timber
Authors: Fujita Masanori , Ohtaki Mayo , Okoshi Yuki , Iwata Mamoru
Published: February 2021

In light of the global environment issues, the authors proposed a building system comprising steel and timber structure (Hereafter referred to as CSTS) and its design method, which consist of rolled section steel and timber. The CSTS is assumed to be mid-rise story building steel structures. This design method use concept of a damage controlled structure with a buckling-restrained brace as a seismic response control member and its analytical model is established based on the available experimental studies. The CSTS is aiming to expand to be used from main structure to floor structure in the building of the non-residential sector and assumed to use materials such as a cross laminated timber for floor structure. This cross laminated timber has a high stiffness and strength because it is joined by multi-layer panels.

In this study, we propose floor structure adapting for the CSTS using cross laminated timber. In- plane shear test of the joint which are consisted of unheaded stud-shear connectors for joint of the CSTS beam and floor structure is conducted. Structural performances of joint of the CSTS beam and floor structure are evaluated. The findings obtained from tests indicate that joint of the CSTS beam and floor structure has a high stiffness and strength.
Scattering of Deicing Salt and Corrosion of Steel Bridges
Authors: Iwasaki Eiji
Published: February 2021

Deicing salts have spread in a large amount and more frequently after the prohibition on the usage of spiked tires. There is some damage in steel bridges due to spreading of deicing salts. Adhesion of deicing salts to girder is divided into two types. The first one is the water leak including deicing salts. The second one is scattering of deicing salts by wind and traffic passage. Steel is rapidly corroded by water leak. However, it is not evident that there is an adverse effect of scattered deicing salts in steel bridges. Therefore, in this paper, the relation between the adhered salts and corrosion of test pieces made of weathering steel is observed. Also, the applicability of weathering steel to cold and snowy districts is discussed.
Some proposals for the Highway Bridge Design System improvement, aimed at increasing of maintenance and rehabilitation efficiency
Authors: Syrkov Anton Vladimirovich
Published: February 2021

This article revises the existing Highway Bridge Design System. The traditional and improved approaches dealing with bridge life cycle are considered. Shown, that success depends primarily on decisions taken at the design stage. Some results of bridge inspections in Russia are presented. The examples of technical and organizational solutions improving are given. The paper spotlights that retrofitting of the existing Design System must be based on feedback from the operation process. Systematization of data from operation of similar facilities, risk analysis, development of routine and heavy maintenance plans, inspection plans and health monitoring systems should start from very beginning of design process. Example of contradiction between design and operation is presented. It’s suggested to create the Data Base, containing the information concerning structures, ineffective in terms of safety and long service life of highway bridges.
Project Materiality Assessment To Increase Lower Impact Building Materials Usage
Authors: Watson Natasha Nancy
Published: February 2021

This paper proposes a technique for the early assessment of the suitability of construction projects to be built using lower-impact building materials (LIBM) such as straw bales and rammed earth. The assessment takes key data from the project’s brief and sustainability aspirations to assess the appropriateness for the use of LIBM. The technique also addresses how different LIBM would affect the buildability of the project on site and identifies sector-specific drivers for the use of LIBM.

This paper provides an overview on the effect the use of LIBM has on potential project geometries and procurement processes. In addition, themes on knowledge, empowerment, and responsibility concerning sustainability within the built environment are also explored.

This work is the development of academic research into the challenges associated with the systematic consideration of embodied impacts and the adoption of LIBM within the UK construction industry.
Study on Large-Scale Repair Plan of the Kanmon Bridge (a Long-Span Expressway Suspension Bridge)
Authors: Yoshida Tadahiro , Maeda Yoshito , Hino Shinichi , Ogata Tatsuo , Nishiyama Shozo , Imamura Takehiro
Published: February 2021

The sliding and rotation functions of the line bearings that support the floor framing stringers have diminished; thus, fatigue cracks have developed in the floor framing around the deteriorated bearings. Also, water that leaks from the expansion joints of the floor framing stringers has caused noticeable deterioration. To prevent further deterioration and damage, replacements of bearings supporting the floor framing stringers, and connection of floor framing stringers were proposed. To secure seismic performance, installations of vibration dampers between the end of the floor framing stringers and the main tower or anchorage were proposed. Additionally, installations of elastic restraining cables were proposed for stability both under normal conditions and during earthquakes. A dynamic analysis of a large-scale earthquake taking into consideration the elasto- plasticity of the steel members was conducted to check the seismic performance.
Strengthening of Concrete Bridges in Germany
Authors: Retzepis Ioannis
Published: February 2021

In the past decades much has been undertaken in Germany in the field of sustainable infrastructure due to limited natural and financial resources. The focus is more on strengthening and retrofitting of an existing infrastructure than on its renewal. Many concepts for strengthening have been developed in Germany and these have been successfully applied in many cases. However, every single case of retrofitting of an existing structure requires an individual concept. Nevertheless, the established concepts can still be applied with certain modifications.
Experimental Evaluation of the Durability of Adhesively Bonded CFRP/Steel Joints in Bridges
Authors: Hedhmati Mohsen , Haghani Reza , Al-Emrani Mohammad
Published: February 2021

Strengthening, repair and retrofit of existing bridges using adhesively bonded fibre reinforced polymers (FRP) composites have attracted a great deal of attention over the past four decades. Despite numerous studies that have been conducted to evaluate the short-term behaviour of FRPs bonded to steel members, the subject of durability is by far less researched. To date, concerns about the long-term performance presents a major obstacle to the widespread application of FRPs in steel bridges. The aim of this work is to identify the most damaging environmental factors and to experimentally investigate the effects of them on mechanical behaviour of Carbon-FRP/steel joints. In this regards, after a review of the literature, both bulk material and bonded specimens were exposed to a number of aging scenarios and tested. The results indicate the deleterious effects of de-icing salts on joint strength by degrading the interlaminar shear strength of FRPs.
Experimental Investigation on Structural Performance of Corroded Beams with Plain and Deformed Steel Bars
Authors: Ma Yafei , Su Xiaochao , Wu Tingting , Wang Lei , Zhang Jianren
Published: February 2021

The bond strength between concrete and deformed bar is provided by mechanical interaction force, while the bond strength between concrete and plain bar is mainly caused by frictional force. The bond mechanisms may result in a different flexural behavior deterioration for different types of steel bars. This paper aims to compare the flexural behavior deterioration of corroded reinforced concrete beams with different covers, types and diameter of rebars. Twenty two RC beams were designed and divided into two groups: one set beams with deformed bars and the other set beams with plain bars. An accelerated corrosion testing was used to promote the determination of strength and stiffness of the beams. Extensive statistical data analysis is performed to compare the performance of beams using different reinforced bars. The results show that corrosion decreases the number of crack and increases the average crack spacing. Corrosion has significant effect on the cracking of the beams with plain steel bars. The ultimate strength and stiffness degradation induced by corrosion are relatively faster in the beams with small steel bar diameter. The effect of steel diameter on the ultimate strength and stiffness degradation in beams with plain bar is larger than that in beams with deformed bar. This study will be useful for the selection of steel bars in structural design.
Life Cycle Assessment of Timber Bridges: A case study
Authors: Niu yishu , Salokangas Lauri
Published: February 2021

Sustainability of bridges can be evaluated by using Life Cycle Assessment (LCA) methodology, which focuses on the potential environmental impacts of a product or project during its life cycle. The impacts are quantitatively evaluated from actions during the life cycle of a bridge, including material production, transport and energy consumption. This paper shows how in principle the LCA can be applied for analysing the sustainability of timber bridges, and conducts the case study of a timber pedestrian bridge. The case study includes five major environmental impact categories, in which it displays that Freshwater Eutrophication Potential has the highest normalised value and material production stage takes the biggest share of all five impact categories in the life cycle of the bridge. In addition, renewable biomass is the largest energy source of timber material. Thus, to some extent, it confirms the sustainability of timber bridge applications.
Tests and Performance-Based Design of Reinforced Concrete Frames Retrofitted with Robust Shape Memory Alloy Braces
Authors: Yang C. S. Walter , DesRoches Reginald , leon Roberto T. , Vega-Behar Pablo
Published: February 2021

Recent moderate and large earthquakes have caused significant structural and non-structural damage to buildings, particularly through the development of soft first stories in older concrete moment frame buildings. These structures have inadequate detailing to sustain the drift levels imposed by the ground motions, so techniques to retrofit them are urgently needed. This paper presents (a) the experimental results of a full-scale two-story two-bay reinforced concrete frame retrofitted with shape memory alloy (SMA) braces in the first story and (b) a proposed performance-based design procedure for new/existing buildings to utilize such braces. The SMA braces are used to help the structure recenter after the event and minimize residual drifts. For the experimental tests, a hydraulic linear shaker was installed on the frame roof of a full-scale building to subject the structure to a series of periodic and random oscillations. The response of individual plane frames with and without the braces was quantified, and the braces were then removed from the retrofitted frame and individually tested. The results obtained from the shaker tests indicated that the SMA braces effectively reduced the first story drifts. The SMA brace-to-beam/column connections in the reinforced concrete frame successfully transferred the brace axial forces to the reinforced concrete frame through the steel beam and column adapters and seismic anchors, without any visible damage to the steel and concrete elements. The individual brace tests showed that the SMA wires could sustain very large strain demands (up to 9%). The number of cycles significantly affected the behaviour of the SMA braces - the larger the number of cycles reached, the higher the recentering capacity but the lower the energy dissipation. Finally, a performance- based design procedure for structures with robust SMA braces is developed by considering variability in the hysteretic parameters of SMA.

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Effective anchorage strategies in retrofit and strengthening
Authors: Silva John F.
Published: February 2021

Retrofit and strengthening of structures is increasingly required for enhancement of survivability and sustainability under extreme loading conditions. The success of such efforts is generally dependent on the robustness of the connection strategies employed, e.g., between the structure and its foundation, between the walls and the diaphragms, and between the strengthening elements and the primary structural frame. Fundamental concepts include connection/system ductility, maximum carrying capacity, maximum displacement capacity, and connection overstrength. This discussion reviews the concepts of anchorage design in the context of seismic demand as framed by the provisions of ACI 318 and ASCE 7; the concepts presented have equal applicability to design for other extreme loading events. Examples of successful connection strategies are presented and a brief review of ongoing research is included.
Replacement of Corroded Cable Stays on Tjörn Bridge
Authors: Laigaard Jakob , Darholm Thomas , Skoglund Martin , Maglica Adriano
Published: February 2021

This paper presents the replacement of cable stays of the 33 years old Tjörn Bridge located in Sweden. The bridge has a main span 366 m and a total length of 664 m. The bridge has a locked coil cable system of 64 cables, where some cables have corroded with a number of wire failures. The reason is exposure to water and ice combined with insufficient drainage. The paper describes the full story from detecting the corrosion problem to restoring the safety of the bridge by replacing the cables in a safe way. The paper presents and discusses the history of inspection and identification of the corrosion problem and the challenges and solutions of the replacement of cables. As several cables had been ex-posed to a corrosion risk, the replacements carried out, required an in depth safety analyses to consider the strength of all cables
Integrated Fibre-Optic Sensor Networks as Tools for Monitoring Strain Development in Bridges during Construction
Authors: Butler Liam J. , Gibbons Niamh , Middleton Campbell , Elshafie Mohammed Z. E. B.
Published: February 2021

Long-term asset management and maintenance of civil infrastructure relies on having access to reliable performance data in order to inform critical decision-making processes. This paper discusses the development and implementation of a robust, innovative and highly distributed fibre-optic sensor network for use as a bridge monitoring and performance evaluation tool. The main steel girders of a new 26.8 metre span half-through steel railway bridge were each instrumented with 80 fibre Bragg grating (FBG) based sensors (spaced at 1 metre) prior to the casting of the concrete deck. Two major challenges with implementing fibre-optic monitoring systems remain prominent: appropriately compensating for strain changes due to temperature, and designing the system to be sufficiently robust to survive installation and continuous long-term operation. This study addresses these challenges through the implementation of a new temperature compensation sensor cable packaging and the deployment of glass-fibre reinforced strain FBG sensor cables with the aim of improving overall network reliability. The completed system is capable of measuring the dynamic strain of all installed FBG sensors simultaneously at sampling rates of 250 Hz to strain resolutions within ±10 microstrain. Data was collected and initial results are presented for the strain developed within the main girders during the casting and curing of the concrete deck. The sensor readings captured the quasi-distributed profile of strains developed along the main girders due to the casting and curing of the concrete deck and have provided insights into understanding the complex thermal response of the structure. This study demonstrates that integrated structural health monitoring systems installed at the time of construction can provide a complete record of the entire load history of a structure. Performance data of this type is invaluable for understanding the behaviour of composite concrete decks, evaluating future structural capacity, establishing long term monitoring programmes, and allowing performance-based asset management decision making.
Smart bridge components (expansion joints, bearings and seismic devices) for intelligent infrastructure
Authors: Islami Kleidi , Meng Niculin , O'Suilleabhain Colm
Published: February 2021

Modern automated structural health monitoring (SHM) systems have much to offer the responsible engineers in the construction, inspection, maintenance and renovation of structures in general, and of key structural components such as bridge bearings, expansion joints and seismic protection devices in particular. In the past, monitoring of such components generally involved the use of separate, independent sensors, connected not to the component but to the main structure and provided, to all intents and purposes, as an afterthought to the design and use of the components themselves. Improving technology is changing this, however, with “smart” components now available, with sensors pre-integrated in their design and fabrication before they leave the factory, and data analysis capabilities improving to include automatic identification of component damage based on general testing and teaching of the system.
Damage Initiation and Propagation Model for Bridge Members
Authors: Ninomiya Yohei , Mizutani Daijiro , Kaito Kiyoyuki
Published: February 2021

In this paper, in order to statistically analysis damage to bridge members and to forecast the initiation and the propagation of damage, a statistical damage initiation and propagation model is proposed. Specifically, the model is a composite model that the initiation process of damage and the propagation process of damage are expressed by different two types of model. When composing such a composite model, it is necessary that the time point of the transition from the initiation process to the propagation process. The time point is certain that the time point of the damage occurrence, however, the damage occurrence is not observed in general inspection works. Therefore, it is also proposed that the estimation method of the time point of damage occurrence, using the temporal discontinuity inspection data to bridges. Lastly, in order to confirm the validity of this study, an empirical analysis is carried out by applying actual inspection data.
Big data and structural health monitoring
Authors: Crémona Christian
Published: February 2021

Structural health monitoring (SHM) has experienced decades of progress in developing sensors and data processing systems, collecting and storing massive amounts of information. Today, for structures’ owners or stakeholders, this data constitutes a promising material of knowledge. This information is a form of “big data”, so-called not only for its sheer volume, but also for its complexity, diversity and timeliness. Learning from these large volume of data is expected to bring significant advances in science and engineering. From banking to retail, many sectors have already embraced big data; grocery stores examine customer loyalty to identify sales trends, optimize their product mix, and develop special offers. Healthcare industry is currently following the same way. While big data come with “big blessings”, there are formidable challenges in dealing with large-scale data sets. Big data challenges offer ample opportunities for “Data Processing” research. Through different examples of bridges’ monitoring, the paper will contribute to the ongoing cross- disciplinary efforts in data science by putting forth encompassing models capturing a wide range of data analytics tasks for structural health monitoring.
Structural Health Monitoring of Crusell Bridge
Authors: Pulkkinen Pekka , Turunen Marko , Toivola Pekka , Eriksson Erik
Published: February 2021

Crusell Bridge is a cable stayed bridge recently built in the city center of Helsinki. In the very beginning of the project the Client City of Helsinki decided to utilize the newest technology in all phases. The project was a pilot project in using Building Information Modeling (BIM) technology in design and construction and finally in monitoring as part of maintenance. In order to develop modern maintenance scheme, an intelligent monitoring system was designed and installed in the bridge. The monitoring system has been tested by a loading test and comprehensive test results have been compared with theoretical calculation analysis. The results verified the design and gave designers guidelines to specify alarming limits to monitoring system. The owner of the bridge will get a summary report from the maintenance system once per year.
Phased array ultrasonic inspection of rib-to-deck welded joints in orthotropic steel decks
Authors: Makita Tohru , Suzuki Toshimitsu , Yagi Naoto
Published: February 2021

Over the last decade, fatigue cracking has been observed in welded joints between the trapezoidal rib and the deck plate in many orthotropic steel deck bridges in Japan. Considering fatigue cracking at rib-to-deck welded joints can cause pavement damage and thus compromise transportation safety, it is necessary to detect and repair fatigue cracks at rib-to-deck welded joints at the early stage of development. This paper presents a new inspection method for rib-to- deck welded joints in orthotropic steel decks using phased array ultrasonic testing. Although existing inspection methods for rib-to-deck welded joints aim at detecting fatigue cracks in the deck plate solely, the developed method examines both the deck plate and the weld bead simultaneously by using an electrically driven scanner holding twin phased array ultrasonic probes. The developed inspection method is implemented at the Meiko-Chuo Bridge, a steel cable-stayed bridge, and the crack detection ability is examined.
Design of floating bridge girders against accidental ship collision loads
Authors: Sha Yanyan , Amdahl Jørgen
Published: February 2021

The Norwegian Public Roads Administration is running a project “Ferry free coastal route E39” which includes replacing ferry crossings by bridges or tunnels across fjords in Western Norway. A floating bridge concept was proposed in the fjord-crossing project for Bjørnefjorden. As there are regular cruise routes passing by the bridge, it raises the concern for the consequences of accidental ship collision with the bridge girder. During the collision, the interactions between the bridge girder and the ship structure can be significant. Thus, in the design of the proposed bridge it is vital to evaluate the safety of the ship and the bridge. In this paper, detailed finite element models of a cruise ship and a steel box girder are developed. The impact scenarios and structural damages are studied. The results show that the proposed bridge girder design is generally safe to resist normal accidental ship collision loads. Numerical model of the whole bridge is also developed for further study of bridge global response subjected to ship collision load.
History of the Bjørnafjorden fjord crossing project
Authors: Eidem Mathias Egeland
Published: February 2021

This paper describe the development of the fixed-link fjord crossing project for crossing the Bjørnafjord, south of Bergen, in Hordaland county in Norway. The Bjørnafjord is over 5 km wide from shoreline to shoreline, with a maximum depth of close to 600 meters. Today, the fjord is crossed by a ferry-connection between Halhjem, and Sandvikvåg. The ferry-connection is a part of the E39 route between Aalborg in Denmark and Trondheim in Norway.

Over the years, many plans has been made in order to try to get a more efficient coastal highway along the west coast of Norway. As a result of this work, many ferries have been replaced with bridges and tunnels along this route. Most notably, the two floating bridges in Norway, the Bergsøysund bridge and the Nordhordlands bridge. Despite the development of longer suspension bridges as well as floating bridges, the Bjørnafjord has long been considered the too big a challenge to cross with a fixed connection. Earlier plans for connecting the the northern and southern part of Hordaland has therefor relied on a long detour around the fjord, in order to avoid building a fixed connection across the fjord.

This paper will describe how the development in offshore technology combined with the development in bridge technology now have made it possible to build a fixed connection across the fjord, as well as the planning-process of the crossing up to the present point in time.
Steel Girder Bridge with RC Deck Retrofit from Non-Composite to Composite Behavior
Authors: Peiris Abheetha , Harik Issam Elias
Published: February 2021

In the past, a number of steel girder-reinforced concrete deck bridges on county roads in the United States have been built as non-composite. Most of these bridges currently have load postings limiting the capacity of bus and truck loads on their roadways. Recent research showed that post installed high strength bolts could be used as shear connectors in rehabilitation work to achieve partial composite design by deploying 30% to 50% of the connectors typically required for a full composite design. This paper presents details on the analysis, design, and field application of post-installed shear connectors on a non-composite concrete deck steel girder bridge in Kentucky. In order to minimize traffic disruption and construction costs, the shear connectors were inserted on the bottom side of the deck through the top flange of the steel girder. While the load rating increased by 132%, field tests conducted before and after installation of the shear connectors showed that the bridge’s live load deflections were reduced by more than 27%.
A New Structural Form Using Concrete Filled Steel I-Girder
Authors: Safi Waheed Ahmad , Nakamura Shunichi
Published: February 2021

In the continuous plate girder bridge with steel I-section and RC slab the critical section is always at the intermediate support where the bending moment is maximum and the concrete slab does not contribute. A new structural solution is proposed: concrete is filled in the area surrounded by the upper and lower flanges and the web. The filled concrete contributes and restricts the local buckling of the flange and the web. Experiments showed that the bending strength of the concrete filled one was 2.5 times larger than the conventional one and the shear strength was 3.0 times. A trial design was carried out for the four-span continuous plate girder bridge with the concrete filled steel I-section and compared with the conventional plate girder bridge. The thickness of the flanges and web can be less than 70% at the intermediate support and 20% at the span center. It is verified that the proposed concrete filled steel I-section is feasible and economical.