bluuebunny/crossref_metadata_2025 huggingface dataset:
Antenatal Service Quality: A Scoping Review
Authors:   Universitas ‘Aisyiyah Yogyakarta, Indonesia, Lestari Yayuk Puji , Kartini Farida ,   Universitas ‘Aisyiyah Yogyakarta, Indonesia
Published: February 2021

ABSTRACT Background: Maternal mortality rate (MMR) is an indicator of the success of health development in a country. The World Health Organization (WHO) has issued a series of new recommendations to improve the quality of antenatal care to reduce the risk of birth and pregnancy complications and provide a positive pregnancy experience. This study aimed to review the antenatal service quality. Subjects and Method: This was a scoping review using an electronic bibliographic database method. Articles were collected from 5 databases, namely Science Direct, PubMed, EBSCO, Wiley, and ProQuest. This study was carried out systematically from 2009 to 2019. The articles used in this scoping review were described in the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) flowchart. Results: Based on 10 articles out of 190 articles according to inclusion criteria, the review results showed that the quality of antenatal care was divided into physical examinations and supporting examinations carried out in antenatal care services, suggestions and infrastructure in antenatal care services, and availability of health personnel in antenatal care services. Conclusion: The quality of antenatal care services is strongly influenced by the standard of the equipment used, the standard of examination, facilities and infrastructure and the availability of health personnel. Keywords: quality, antenatal care, scoping review Correspondence: Yayuk Puji Lestari. Universitas ‘Aisyiyah Yogyakarta. Jl. Ringroad Barat No.63, Mlangi Nogotirto, Gamping, Rice Field Area, Nogotirto, Kec. Gamping, Sleman Regency 55592, Yogyakarta Special Region. Email: yayuk.pujilestari1892@gmail.com. Mobile : 085349033588. DOI: https://doi.org/10.26911/the7thicph.03.31
Developments in the wind engineering of tall buildings
Authors: Irwin Peter A.
Published: February 2021

The number of tall buildings above 200 m in height has been growing exponentially in the last two decades, largely due to mass migration of populations around the world into cities where land is at a premium. There is no sign that this trend will end soon. A large number are now in the 200 m to 600 m range and the tallest are approaching 1000 m. The importance of wind loading and serviceability under wind action has grown along with the increasingly extreme heights and slenderness of many of these structures. Whereas wind loading used to be taken as something to be determined after most of the important design decisions had already been taken, it is now recognized (as it has been for a while for very long span bridges) as something that needs to be accounted for right from the outset. It is common now for shaping workshops to be undertaken in the wind tunnel soon after commencement of design so as to avoid difficult and expensive to solve problems emerging late in the process. As well as shaping the building aerodynamically, the use of supplementary damping has become much more common and is often acknowledges as a crucial part of structural optimization. The paper will provide examples of how wind engineering influenced the design of a number of tall buildings.

A recent development in wind engineering is the proposed adoption of Performance Based Design principles that have proven very beneficial in seismic engineering. The capability now exists to undertake full time history analysis of a tall building during a severe storm and to use Incremental Dynamic Analysis to explore its final collapse mode. This allows the true wind performance of buildings of buildings to be assessed in much greater detail than before, an important consideration if tall buildings are to be used a shelter in place along hurricane ocean lines. Findings from these studies indicate tall buildings, currently designed to remain fully elastic even at ultimate wind loading, have considerable untapped reserves of structural strength. The biggest challenges lie in the area of serviceability and cladding rather than structural strength. Serviceability issues can be largely resolved by supplementary damping systems but the current reliability of cladding under impact from wind loads, debris and wind driven rain appears to be in need of improvement.
Monitoring intrinsic forces of a steel multi-girder bridge with frozen expansion bearings through rehabilitation
Authors: Hasan Istiaque , Dubbs Nathaniel
Published: February 2021

A Structural Health Monitoring (SHM) system was designed and installed on a steel two‐span continuous multi‐girder bridge to track key performance metrics during construction of a nearby major industrial complex. The goals of the monitoring system focused on identifying and tracking performance of the bridge’s unique movement mechanisms and variation of intrinsic forces within the girders. During the pre‐ construction monitoring period, the structure’s temperature‐based response signature was evaluated for each performance metric. This analysis showed that the original expansion bearings at the bridge’s single abutment were frozen. After one year of monitoring, the owner of the bridge decided to carry out a rehabilitation project. The rehabilitation allowed for the opportunity to compare the bridge’s response signatures before and after bearing replacement. The main objective of the paper is to present the findings related to how the bridge performed after the replacement of expansion bearings, specifically how the development of intrinsic forces in the steel girders was altered.
Experimental Investigation of Post-cracked Flexural Behavior for PC Girder Bridges
Authors: Hu Zhijian , Du Reirei , Wu Fei , Yuan Shuaihua , Wang Shaobin , Xiao Donghua
Published: February 2021

Extended studies are more and more needed for evaluating the post-cracked flexural behavior of PC (prestressed concrete) bridges where the design concept of eliminating cracks cannot be satisfied. In this paper, an experimental program is provided with six scaled specimens to analyze post-cracked flexural behavior of prestressed concrete girders. Mechanical properties, such as ductility, flexural rigidity and load-bearing capacity, are examined according to grouting, loading types and deflections at midspan. The results reveal that grouting provides better behavior by increasing ductility and crack resistance for PC structures. Load cycles have insignificant influence on cracking, ultimate loads and flexural rigidity of the prestressed concrete beams. However, load cycles may decrease non-prestress reinforcement (NPR) yielding loads by 5-12% and will reduce ductility by decreasing ultimate deflection. Furthermore, empirical equations have been presented and validated for evaluating flexural rigidity and load-bearing capacity for PC beams with cracks.
Innovative Solutions to Seismic Design Challenges for the SFOBB I-80 WB Ramps at Yerba Buena Island
Authors: Lee Hohsing
Published: February 2021

The I-80 Westbound (WB) ramps at Yerba Buena Island (YBI) are comprised of five complex curved structures that were designed to provide access to the new east-span of San Francesco Bay Bridge (SFOBB). The construction contract of the project was awarded in late 2013. Yerba Buena Island is located in very high seismic zone within the San Francisco Bay. Two major earthquake sources are the Hayward fault at about 12 km east of the project site and the San Andrea faults at 18 km west of the project site. The terrain at the bridge site highly varies with the ground surface elevations, which make seismic design very challenging. This paper discusses a number of innovative design solutions; foundation, superstructure, seismic deck joints, in-span hinges, spherical bearings, and etc. to deal with the stringent seismic design challenges.
An efficient seismic retrofit for the Capodichino viaduct
Authors: Viviani Marco , Viviani Enrico , Mardegan Andrea , Contin Alessandro
Published: February 2021

Built environment in Europe has become dense with infrastructures and buildings packed in a restricted space. In many countries the laws explicitly promote the cities densification to avoid further urban sprawl. For many years the densification was debated without taking into account the need for a general seismic update of infrastructure and the protection of the cultural heritage. The Capodichino viaduct is a remarkable case of seismic retrofitting in a highly urbanized, seismic area. This paper presents the concept and the installation of new piers cap system that allowed retrofitting of the bridge without any modification of the piers and foundations capacity, while the structure was in use.
Seismic assessment of a vernacular rammed earth building
Authors: Librici Camilla , Oliveira Daniel V. , Silva Rui A.
Published: February 2021

Rammed earth constructions represent a valuable cultural heritage of vernacular architecture, whose significance has acquired even more importance in the last years with the renovated interest for this sustainable building technique. The aim of this work is to develop a FEM model typologically representative of a Portuguese vernacular rammed earth construction in order to characterize numerically its seismic performance and raise awareness about the level of improvement introduced by two compatible strengthening techniques: textile reinforced mortar (TRM) and a ring beam applied at the top of the walls.
Modal parameter identification of a curved cable-stayed model bridge based on EDA and DATA-SSI
Authors: Zhou Xiaohang , Shan Deshan , Li Qiao
Published: February 2021

For bridge health monitoring, the measured data may be unreliable due to various interferences. In order to get a reliable modal parameter identification result of a bridge, it is vital to have an inspection and a pre-processing on the bridge health monitoring data. Firstly, exploratory data analysis (EDA) was adopted to inspect the data quality, and the unreliable data measured from malfunctioning sensor was removed. Then, outlier analysis was performed to eliminate the abnormal data points from the data set. In the end, data driven stochastic subspace identification (DATA-SSI) combined with stabilization diagram was applied to identify the bridge modal parameters. A large scale curved cable-stayed model bridge was taken as an instance to verify the proposed method. The comparison of the modal parameter identification results of the original and the pre-processed data shows that the proposed method is effective, accurate and valuable.‌
A novel Quality Control Framework for the management of existing bridges
Authors: Hajdin Rade , Tanasić Nikola , Kušar M. , Amado Joao
Published: February 2021

The paper presents a framework to evaluate key performance indicators (KPIs) in qualitative man- ner. This framework is the basis for establishment of Quality Control plans for existing bridges. It addresses the dynamics of the damage processes that allows predicting the point in time, from which the performance goals are not met anymore. The KPIs are defined to address not only road users’ but also owner’s or operator’s perspective as well as environmental and societal concerns. To this end the RAMSSHE€P approach gas been modified. The proposed framework is also illus- trated on a simple example.
Decision support for maintenance and upgrading of existing bridges
Authors: Honfi Dániel , Leander John , Björnsson Ivar , Ivanov Oskar L. , Plos Mario , Zandi Kamyab , Magnusson Jonas , Lechner Thomas , Gabrielsson Henrik
Published: February 2021

Maintenance of transportation infrastructure assets can be relatively expensive, since it does not only include the direct cost of interventions, but also the indirect consequences of traffic disruptions. To make optimal decisions about maintenance actions, including rehabilitation and upgrading, reliable information about the performance of existing structures is needed. However, obtaining such information might require significant efforts and can be done in various ways. The purpose of an ongoing Swedish research project BIG BRO is to develop a framework for a decision support methodology that can be used for implementing maintenance strategies for bridges on a rational basis. The present paper provides a brief overview about the project as well as describes some of the ongoing work.
Filling of strand corrosion products in cracked concrete based on accelerating corrosion method
Authors: Wang Lei , Dai Lizhao , Ma Yafei , He Xianfeng
Published: February 2021

An experimental study is proposed to investigate the filling extent of strand corrosion products during concrete cracking. A prediction model of crack width is developed incorporating the filling of corrosion products and geometric properties of strand. The relationship between the rust filling ratio and crack width is addressed. The restraint effects of stirrups on the rust filling ratio also are discussed. Twelve concrete beams were designed and accelerated toward corrosion-induced cracking. The proposed model is verified with the experimental results. Results show that the rust filling ratio increases with increasing crack widths before a critical value. After crack beyond the critical width, the rust filling ratio varies around the constant. The critical widths of maximum rust filling ratio in specimens with stirrups and without stirrups are 0.48 mm and 0.56 mm, respectively. The critical crack width of maximum rust filling ratio decreases 14.3% by using stirrups. Stirrups can restrict the corrosion-induced crack propagation and reduce the rust filling ratio.
Effect of Residual Stresses on the Overall Buckling Behavior of Welded Box-section Columns under Axial Compression Loading
Authors: Hu Ying , Adomako Kumi G. , Feng Liangliang , Shen Le , Zhang Weifu , Nie Shidong , Cui Jia , Xu TanChuMin , Xu Lei
Published: February 2021

Owing to progressively increased demands of high-strength steels (e.g. S460, S690 and S960) in steel construction, an experimental program was developed to study welded box-section steel columns under compression accounting for residual stress distribution. In this paper, a series of numerical analyses were performed to identify the effect of residual stress on the overall buckling loads of the welded box-section columns. At the end of the study, it was observed that residual stress distribution has little influence on the overall buckling loads of the welded box-section steel columns. It was also observed that dimensional properties and residual stress ratio α/β have a minor and a significant influence respectively on the overall stability coefficient of welded box-section steel columns.
Multi span suspension bridge on floating foundations – behaviour under operation
Authors: Villoria Bruno , Veie Johannes , Holtberget Simen Helgren , Jena Parthasarathi
Published: February 2021

A multi-span suspension bridge on floating supports has been evaluated and found to be a suitable option for the crossing of Bjørnafjorden on the West Coast of Norway. The proposed concept combines known technologies such a multi-span suspension system, floating supports inspired by the tension-leg platforms technology commonly used in the offshore industry and a top cable connecting the top of the four pylons.

Such a construction would pioneer the field of strait crossings at extreme depths for which conventional bridges are not suitable. The absence of similar constructions and therefore the lack of references constitute significant challenges for the design group.

The present article describes the global behaviour of the structure under normal operating conditions and summarizes the main findings from the investigations carried out in the initial study phases.
Comparison of methods for determination of load-bearing capacity of I-73 and KA-73 precast concrete bridge beams
Authors: Lehký David , Novák Drahomír , Kucek Martin , Nezval Michal
Published: February 2021

A comprehensive procedure to determine a load-bearing capacity I-73 and KA-73 precast concrete bridge beams using the advanced methods of statistical analysis based on simulation technique of Monte Carlo type in combination with nonlinear finite element method analysis is presented in the paper. Degradation processes over time caused by carbonation of concrete and chloride ingress together with consequent corrosion of prestressing tendons are taken into account. Mathematical modelling of these phenomena is based on information about the current state of the investigated bridges obtained from diagnostic surveys, including the degree to which building materials have deteriorated. Results of probabilistic approach are compared with those obtained using a global safety factor method according to the Eurocode 2 and the fib Model Code 2010 method called Estimate of Coefficient of Variation. Shortcomings and advantages of all utilized design/assessment methods are discussed.
Hagwilget Bridge, Canada:
Authors: Tarrell Jack
Published: February 2021

This paper discusses the concept development, detailed design and execution of the stiffening truss node replacement under live traffic for the Hagwilget Bridge. This complex rehabilitation project will extend the bridge service life by 40 years. Hagwilget Bridge is an 85-year old, 140 m (460') suspension bridge across the Bulkley River near Hazleton, BC. The bridge connects a First Nation community and the local hospital to the main highway with the only alternative route being a 4-hour drive on dirt roads. An innovative system was designed to allow replacement of entire stiffening truss nodes in 2 days, with no more than two, 20-minute traffic interruptions. This paper describes the design of temporary works and the complex construction procedures.
Load Rating of a Steel Bridge by Inclination Measurement
Authors: Su Di , Eid Jonathan , Nagayama Tomonori
Published: February 2021

Bridges are aging in Japan and the maintenance of these structures has become a major issue. In this current research work, in order to fully exploit in-service data obtained from structural monitoring, a methodology for evaluation of an existing steel bridge has been proposed to update live load effects and improve structural performance evaluation. Inclination data are chosen as a live load effect for all limit states then processed using extreme value theory and reliability theory. Incorporating the results from finite element analysis for resistance represented by inclination, the reliability index of the structural member is deduced by utilizing Second Order Reliability Method (SORM) together with its rating factor by Load and Resistance Factor Rating (LRFR). Rating factor results show higher rating than the procedure detailed in the AASHTO Manual for Bridge Evaluation (MBE), which is majorly based on design condition assumptions.
Edge Distance for Mechanical Fastening of Steel Fatigue Cracks
Authors: Fujita Masanori , Okazaki Shunsuke , Miida Yuki
Published: February 2021

Fatigue cracks of steel structural members applied by overload, repeated load occur. As a countermeasure, there are some repair methods of steel fatigue cracks such as a stiffening plate method, a weld repair method, a stop-hole method, and a mechanical fastening method, and they are used corresponding to the characteristics. Among them, a mechanical fastening method repairs steel fatigue cracks without welding. Crack progress after this construction is less and the thermal strains by welding do not occur.

In this paper, tensile test and FEM analysis of steel structural members using the mechanical fastening system are conducted. Fracture behavior affected by the edge distance of the mechanical fastening components is simulated using FEM analysis and the effective edge distance of the mechanical fastening is discussed.
Structural Evaluation and Load Rating of Lorne Bridge: A Historic Open-Spandrel Arch Bridge-Case Study
Authors: Salib Sameh , Werner Jonathan , Liu Karen
Published: February 2021

Open-spandrel arch bridges possess a unique combination of elegant architectural aesthetics and robust structural behaviour. While classified as such, Lorne Bridge, further, presents a historic icon and landmark of the city of Brantford, Ontario, Canada. The bridge was built in 1923 with three continuous arch spans that range between 42m and 47m, crossing the Grand River, and annexed to a 20m single span railway overhead structure. The steel-reinforced concrete superstructure of each of the main bridge spans consists of an arch and variable height solid spandrel walls supporting the bridge deck. Massive plain concrete piers and abutments carry the superstructure and are ultimately founded on bedrock.

Recently, a broad study including site inspection, condition survey and structural evaluation was carried out as a step towards maintaining both the heritage and function of the bridge in the future. The age, condition and complexity of the bridge warranted a sophisticated analysis method in order to achieve reliable evaluation conclusions. Therefore, the bridge was analyzed using a non-linear three Dimensional Finite Element Modelling (3D-FEM). The analysis represented the major surveyed concrete cracks of the bridge as well as investigating the influence of post-steel yielding of various individual superstructure components on the global behaviour and strength of the bridge.

The evaluation concluded that specific loads such as temperature, which only marginally utilize the strength of most structures, can dictate the load rating herein. Moreover, utilizing two dimensional/simplified methods of analysis for such bridges can neither predict the actual structural behaviour nor interpret the associated deficiencies. Finally, the study recommends that future design standards mandate more stringent requirements for evaluating open-spandrel arch bridges.
Reviving and Repurposing the Iconic TWA Flight Center
Authors: Buckley Ian , Wilcoxon Dan , Macht Jeremy
Published: February 2021

The Trans World Airlines (TWA) Flight Center, at John F Kennedy International Airport, New York is one of the most iconic buildings of the 20th Century. Designed by architect Eero Saarinen, the futuristic design was widely considered symbolic of the Jet Age.

This paper presents a brief overview of the historic building structure, and describes how a series of structural alterations are being made to transform the former airline terminal head-house into the lobby and reception areas within a new hotel and conference center development. It details how creative design can be used to deliver adaptive re-use projects which move beyond basic restoration to deliver elegant structural solutions to address the future and continued life of existing buildings.

The latest 3D technology was leveraged throughout the project, including point cloud scanning, combined with Revit models of the structure constructed from record drawing information.
Study on Tensional Countermeasures for
Authors: Zhuang Dongli , Xiao Rucheng , Da Xiao
Published: February 2021

For easily calculating the cable tension force of cable-stayed bridges with parallel strand stayed cables, the cable-stayed bridges were simplified as a equivalent model consisting of serially or parallelly interconnected springs which were employed to instead of bridge elements such as towers, cables, and beams. . For this equivalent model, simplified formulas for calculating the tension force were deduced, and a corresponded calculation process was presented. The comparison of these proposed formulas with other calculation methods showed that the proposed formulas are reliable. A parametric study centralized on the proposed formulas was carried out in order to understand the characteristics of them. The study results suggested that stiffness ratio and tension coefficient had significant effects on the discrepancy of calculation, and the tension coefficient was more sensitive to the discrete discrepancy and total discrepancy of the final cable’s force; equivalent tension has many advantages in practical construction operations, so a reasonable tensional countermeasure should be chosen according to the structural stiffness and the right tension coefficient should be estimated according to the tension range of jack at the same time.
Non-Destructive Testing for Detecting the Corrosions of External Post- Tensioned Tendons
Authors: Lee Joo-Hyung , Cho Jae-Yeol , Shin Sung-Jin , Hong Jeong-Mo , Lee Jae-Hoon
Published: February 2021

Recently, a failure of external post-tensioning strands was found in a bridge in Seoul, Korea. It was the first time that the failure of tendon in PSC box girder bridges was reported in South Korea. A variety of attempts to find out the reason of tendon failure and to improve tendon maintenance system of PSC box girder bridges have been made after the failure. Out of many attempts, two types of NDT(Non-Destructive Testing) methods, MMFM(Magnetic Main Flux Method) and MFL(Magnetic Flux Leakage) were applied and compared to evaluate the capability and the effectiveness of the two methods to detect and quantify the deterioration associated with corrosion of strands. Two steps were taken to do so. First, both of the two NDT technologies were carried out for calibration and blind test, with damaged tendons in a laboratory environment. Afterwards, the external tendons were examined by the NDT systems inside the actual PSC box girders of the two bridges. This paper summarized the laboratory and on-site NDT test results to share the experiences.
Assessing the Impact of Improper Placement on Reinforced Concrete Beam Behaviour
Authors: Zhang Jiachen , Brault Andre , Hoult Neil A.
Published: February 2021

The recent construction booms in Dubai and China have often required the use of unskilled labour, which can lead to defects in the structure such as voids in reinforced concrete members. The goal of this research was to use sensors to explore the impact of poor concrete placement on reinforced concrete behaviour. Two beam specimens were constructed: a control, which was well vibrated, and a defective beam, which was not well vibrated resulting in extensive voids. Distributed fibre optic strain sensors were installed on both the longitudinal and transverse reinforcement bars. Digital image correlation was used to track crack development. It was found that the poor concrete placement had no impact on stiffness, capacity or failure mode. The distributed strain and digital image correlation data highlighted subtle differences in strain and cracking behaviour between the two specimens.
Use of Extra Coating Thickness on Epoxy-Coated Bars in Concrete Deck Replacement
Authors: Villamizar Sandra , Hull Henkhaus Rachel E. , Ramírez Julio
Published: February 2021

Current standard specification for epoxy-coated steel reinforcing bars (ASTM A775/A775M) allows coating thicknesses between 175 to 400 µm. This paper presents an experimental program conducted to evaluate the bond performance in normal-weight concrete of epoxy-coated bars with coating thickness up to 460 µm. Two different bar sizes were investigated, No. 16 and No. 29 bars. Single splices as well as splices of bundled bars were evaluated in the experimental program. The results of the study were implemented in the form of design recommendations for bond of epoxy-coated bars with thicker coatings. The goal is to enhance the future sustainability of concrete bridges by improving the performance of epoxy-coated bars as a corrosion protection system.
Wind Load Evaluation based on the Field Measurement Data for the Design of a Suspension Bridge
Authors: Jung Kilje , Kim Chong Hyun , Kim Gi Nam , Yoon Eui Taek
Published: February 2021

This study has been performed to evaluate the wind load for design of a suspended bridge. A meteorological station was installed at each pylon area and the data was collected. Additionally, wind data from other weather stations located nearby the site was also considered.

The basis wind speed has been estimated by extreme wind analysis using historical extreme wind records, which are measured nearby two representative meteorological stations. In order to estimate the basis wind speed for 100 years, the Gumbel’s extreme statistical analysis is performed.

The turbulence properties of fluctuating wind speeds such as turbulence intensity, spectrum and coherence also have been verified based on the field measurement data. The evaluated turbulence intensities are compared with the engineering model. The turbulence spectra were calculated using the high wind speed recordings and compared to the Kaimal Spectrum.
Lessons learned from construction of several extradosed bridges
Authors: Bajo Pavía Carlos , Martín-Tereso Luis , Sánchez Juan José , Herrero J. Emilio , Franczewski Tomasz , Stachura Michal
Published: February 2021

The creation of the concept and denomination of the extradosed bridge is attributed to the French engineer Jacques Mathivat, who, in 1988, coined this term for the first time referring to the solution he proposed for the Àrret Darré Viaduct. In that proposal, prestressing cables extended out from the upper part of the deck were anchored to a low tower in order to gain eccentricity. Even though this option implied material savings with regard to other more conventional solutions, it was rejected. Nevertheless, Mathivat’s proposal inspired the Japanese who, in 1994, built Odawara Blueway Bridge in Japan. Since then, approximately one hundred extradosed bridges have been built all over the world.
Considering constructability in precast construction
Authors: Wium Jan , Mostert Lourens
Published: February 2021

The construction industry in South Africa has traditionally relied upon in‐situ concrete construction for much of its infrastructure development. However, prefabrication of concrete elements can accelerate the project schedule, improve quality and increase durability. More use of concrete prefabrication can support the Government’s goal of providing infrastructure to eradicate poverty and unemployment, and to provide citizens with quality education by 2030.

This paper reports on a research project which is aimed at the compilation of information to help projects teams to consider prefabrication as a project alternative. Several parameters can influence such a decision. In this paper technical aspects are considered in the decision process, and specifically the choice of connections between precast elements.

Although much information is available in international literature on typical connection details. The local industry relies much on unskilled labour, with resultant quality management challenges. The choice of connections by designers therefore needs to include ease of construction, low material costs, and the potential for rework.

Early contractor involvement is seldom possible, and designers need guidance towards suitable choices which will enhance constructability. This paper presents the results of a study which identified the parameters to be considered for connection design in the local industry. It also identifies advanced concrete technologies which can benefit connection design in the local market. By making the correct design choices, the project constructability is improved. This information is also of value to other developing countries who can benefit from this construction method.
Constructing the Abraham Lincoln Bridge
Authors: Brestin John , Osses Claudio , Buch Kevin , Finke John
Published: February 2021

The Abraham Lincoln Bridge is a 3-tower cable-stayed bridge connecting Louisville, Kentucky to Jeffersonville, Indiana. The design included an innovative foundation layout, cable-stayed detailing that simplified construction, and probabilistic 100 year service life design. The design contemplated the construction approach preferred by the Design Build contractor. This collaborative approach between the designer and contractor was critical to achieving efficient design elements such as the anchor box, anchorages at the deck level, and tie downs. Yet, despite careful planning, challenges presented themselves during construction, such as deficiencies of concrete materials and difficulties during shaft construction. This paper takes an in depth look at these challenges that arose during construction as we endeavour to share the knowledge gained, not from what went well, but rather from our collective failures.
Parametric study and reliability-based evaluation of alternate load path design in reinforced concrete slabs
Authors: Droogné Didier , Caspeele Robby , Taerwe Luc , Herraiz Borja
Published: February 2021

In normal design situations, RC slabs are in general designed using small deformation theories while taking into account linear elastic behaviour. However as indicated by previous large structural failures the importance of considering the behaviour of RC slabs at large deformations is as important. Based on multiple experimental studies it is clear that RC slabs can develop alternate load paths and consequently generate a significant strength reserve by membrane action once large deformations occur due to the removal of a load-bearing element. This strength reserve is of major importance as this could result in an important increase of the structural robustness for RC buildings. In this contribution a parametric study with a numerical model is performed to investigate the design possibilities on membrane action in RC slabs. Next the reliability of the developed membrane action and alternate load path is calculated for a reference case which is subjected to the removal of a central support considering the static and pseudo-static behaviour.
Multi-span suspension bridge on floating foundations - behaviour under ship impact
Authors: Dørum Cato , Sha Yanyan , Storheim Martin
Published: February 2021

The multi-span suspension bridge on floating Tension Leg Platform (TLP) foundations is one of the proposed concepts for the crossing of the E39 Bjørnafjord in Norway. One of the challenges in the design of the fixed link is to ensure sufficient robustness with respect to ship impact. In this work, the structural response to a ship impact event is evaluated using nonlinear finite element analysis. The simulations are based on a bow model of a 186 m length over all container vessel, which is estimated to transit the bridge crossing weekly. Impacts from a conventional container vessel bow without ice reinforcements cause minor damage to the floater hull. Most of the energy is dissipated in the striking vessel. Impacts from an ice-reinforced vessel gives considerable more damage to the floater hull. The damage extent for all the simulated impacts are repairable on site. However, impacts from the conventional vessel cause only minor denting and can be repaired at a convenient time, whereas impacts from the ice- reinforced vessels necessitates major repair work.
Seismic Fragility Curves using Natural and Synthetic Ground Motions
Authors: Sarkar Pradip , Davis Robin , Pragalath D. C. Haran
Published: February 2021

Fragility curves are useful tools for the probabilistic assessment of the seismic performance of buildings. Nonlinear structural analyses with uncertainties in load and resistance are required to develop fragility curves. A statistically sufficient number of earthquake ground motion records should ideally be obtained from past records of the region of interest to have a satisfying fragility curve. However, the number of available earthquake records in many seismically active zones is limited. In such a situation, use of the synthetic ground motions is an accepted alternative for fragility analyses of buildings. This paper compares the seismic fragility curves obtained from synthetic and natural ground motion records. It is found that synthetic ground motions result in conservative fragility curves with lesser dispersion in drift demand when compared with natural recorded ground motions.
Sir Ambrose Shea Lift Bridge – Newfoundland and Labrador, Canada
Authors: Ajrab Jack , Mccall Joanne , O'Connell Ryan
Published: February 2021

The new Sir Ambrose Shea Vertical Lift Bridge is located in the Province of Newfoundland and Labrador on the east coast of Canada, and was built as a replacement to an existing structure constructed in 1961 that had reached the end of its useful life. It is a three-span structure, with a movable centre span (vertical lift span) flanked by two simple fixed composite plate girder spans. The towers for this lift bridge consist of a three dimensional steel truss, shaped representative of sails. Each tower component is connected by a three dimensional exoskeleton truss which houses the machinery to operate the lift span. The new bridge was designed to be durable, efficient, and reliable as well as being an aesthetically pleasing structure with architecture to reflect the local culture and tourism potential of the region. The new bridge was constructed adjacent to the existing bridge in order to minimize disruption to the local fishing boats and road traffic.
Veterans Home Bridge Rehabilitation
Authors: Arellano Eduardo , Skabar Kip , Kishimoto Yuki
Published: February 2021

Bridge rehabilitation projects are completed to permit current design loads and State legal loads on existing structures. This paper presents a rehabilitation case study of the Veterans Home Bridge, a historic orthotropic steel deck arch structure that was constructed with distinctive aesthetics and in an era that warrants its listing in the National Register of Historic Places (NRHP) as a contributing element to the Minnesota Soldiers’ Home Historic District. Following a fracture critical inspection which identified critical deficiencies that required urgent repairs, a load rating analysis was completed for the steel truss, which resulted in a 12 Ton Gross Vehicle Weight (G.V.W.) load posting requirement. Because minimum emergency vehicle G.V.W.s exceed this load restriction, the bridge was closed to the public. Multiple repair options were evaluated and a detailed rehabilitation design was completed to facilitate American Association of State Highway Officials (AASHTO) HS-20 Design Truck loading and to meet the aesthetic requirements of the Minnesota State Historic Preservation Office (SHPO).
Method for Validation of long-term Temperature Measurements from Sensors
Authors: Abdel-Jaber Hiba , Glisic Branko
Published: February 2021

Structural Health Monitoring (SHM), which holds promise for quick and reliable assessment of structural condition, requires reliable long-term measurements. While commercially available sensors can provide accurate measurements, none have been tested on longer timescales to ensure stability. This study deals with the creation of a method for the validation of temperature measurements without the use of a redundant monitoring system. Reliability of temperature measurements is particularly important because they are often used for the compensation of other measurements, such as strain. The method is based on comparison of measurements to easily obtainable public data, such as data from meteorological agencies, and is presented through application to measurements from sensors installed on Streicker Bridge in Princeton, NJ. It was successfully used to confirm stability of multiple sensors and detect malfunction of other sensors.
The Existing Champlain Bridge - Strengthening Measures
Authors: Griezic Andrew , Pepin Francois , de Gaspé Lizotte Jean , Lasheras Gustavo , Demers Francois
Published: February 2021

The superstructure of the 50 approach spans of the Champlain Bridge consists of a highly integrated system with seven deep precast post-tensioned girders, transversely post-tensioned diaphragms and cast-in-place infill deck slabs. Deterioration and signs of corrosion observed in many of the girder PT tendons led the corporation managing the Bridge to initiate a major girder strengthening campaign to ensure user safety and that the structure remains open to traffic. Six strengthening systems were designed to secure all 100 edge girders, each system having a specific rehabilitation purpose and designed to address multiple constraints. For each system, the main principles behind the design, its intended purpose (emergency or permanent repair) as well as the many considerations in developing each system are described.
The Existing Champlain Bridge – Developing a Customized Inspection and Assessment Methodology
Authors: Zhang Cheng , Langlois Andrei
Published: February 2021

A bridge at the end of its lifespan tends to deteriorate at an exponential rate. Given the unique challenges of the Champlain Bridge located in Montréal, a customized inspection program was developed to monitor the condition and behaviour of the bridge approach spans. The cornerstone of this program is a set of customized inspection criteria to assess the degraded superstructure elements and the installed strengthening systems. An Integrated Grading System (IGS) rating the overall performance of a reinforced superstructure element was also developed. The IGS rating is based on an algorithm that feeds on inspection data from each individual component and considers the complexity of the interactions between the original structure and the added strengthening systems. This paper presents an example of the inspection criteria and IGS rating system developed specifically for the approach spans of the Champlain Bridge.
Deflection estimation of a steel box girder bridge using multi-channel acceleration measurement
Authors: Nagayama Tomonori , Zhang Chunbo
Published: February 2021

The deflection of a bridge is an important physical quantity, which is usually specified in design. The deflection can also be utilized in the estimation of traffic load. However, the measurement is oftentimes not practical. Reference points for displacement sensor are usually not available. While deflection estimation by double‐integration of acceleration measurement provides a simple and inexpensive deflection estimation, this approach suffers from large integration errors. In this study, deflection estimation without the integration errors only using accelerometers is proposed. The acceleration signals are used to estimate girder inclination. By combining this inclination and the vertical acceleration through a Kalman filter, the bridge deflection is evaluated. A steel box girder bridge is instrumented with wireless tri‐axial accelerometers. The deflection estimated through the Kalman filtering is compared with references.
Hybrid structure for the ArtLab EPFL pavilion
Authors: Menétrey Philippe , Maas Joachim
Published: February 2021

The ArtLab pavilion groups three distinct buildings under one same roof. This project, developed by the Japanese architect Kengo Kuma, winner of the 2012 competition, was built on the EPFL campus, next to the Rolex Learning Center, from 2014 until 2016.

The pavilions, with their unifying roof, create a contrast between traditional slate roofing and contemporary design with their dramatic length and various inclined planes as proposed by the architect. But, this contrast also characterizes the structure: while it is made of simple frames, each of them have a specific geometry which calls for modern construction methods and innovation.

The variable geometries of the frames were generated using a 3D model of the pavilions to guaranty the continuity of the different roof planes. To obtain constant cross-sectional frames, a hybrid structure composed of a wooden frame coupled by two frames made of perforated steel plates was developed. Using non-linear material laws, a numerical model was validated with experimental results of bending tests and then used to design of these hybrid frames.

Finally, the northern roof cantilever was created with a three-dimensional pleated structure made of solid wood. The behaviour of this structure was modelled with shell finite elements and verified on site by monitoring the displacements of the roof during construction.

These pavilions demonstrate that innovation can improve the quality of construction.
Using game engines in visualizations and simulations of the bridges in the E39 fjord crossings project.
Authors: Madsen Preben Ren
Published: February 2021

As part of the design, development and planning of the E39 fjord crossing project, the Norwegian Public Roads Administration (NPRA) is looking at the possibility of using game engines for real time rendering and animations of the bridge concepts. The development of the visualization tools in the gaming industry, with the likes of Virtual Reality (VR), Augmented Reality (AR) and more advanced game engines, enables much more detailed models than what has been possible before. The NPRA would like to use these tools as an aid in the design, construction, maintenance and operation of the fjord crossings. By introducing 3D-models of the constructions and the terrain in all stages of the project, the models can be imported and further developed in 3d-modelling programs and game engines used by the game industry in order to create advanced visualizations and simulations. This paper demonstrates how game engines can be used as a tool to incorporate scientific data and analysis and display these data through real time visualizations and simulations. In this case, the horizontal mode of the two TLPs due to wind, current and wave forces.
A Critical Take on Eurocode 2 Concerning the Assessment of Shear Capacity of Reinforced and Prestressed Concrete
Authors: Hertle Thomas , Gebbeken Norbert , Hertle Robert
Published: February 2021

Most of the infrastructure in Europe dates back to the midst of the 20th century. In recent years it became more and more important to conserve and revamp this existing network of traffic roads and bridges to meet the actual and future requirements of the society. With the introduction of the DIN 1045-1 in 2001 and the actual generation of the Eurocodes in 2012-2013 the re-evaluation of existing structures, i.e. especially bridges, became more difficult when using these technical rules as a base. In many cases the new calculations resulted in a significant smaller load-bearing capacity than the constructions were designed for back in the day. In particular, re-evaluations of the shear capacity of these structures show big discrepancies between the amount of steel that is needed depending on the old regulations or the new Eurocodes. These discrepancies are shown by typical examples and possible ways to handle the results will be discussed. By looking at advanced shear models and non-linear finite element calculations possible further developments of the shear-limit- state formulation are suggested.
Comparison of Shear Design Provisions of Structural Concrete Members Used in Various Approaches
Authors: Wei Sihang , Kuchma Daniel
Published: February 2021

As multiple one-way shear design provisions for structural concrete members appeared in the recent decades and have been adopted by various design codes, it is important to assess how the design would be influenced by these approaches. A few approaches were selected from the most widely used national code provisions and other relationships proposed by researchers. This paper overviewed the mechanisms of shear resistance considered in each approach, and a thorough review and summarization was made. The application of the three principles of shear design in each approach is discussed. The factors affect the concrete and the steel contributions in each approach are compared. And the influence of prestressing force on shear resistance is also studied.