bluuebunny/crossref_metadata_2025 huggingface dataset:
Durability of GFRP Bars with Different Bar Diameters
Authors: Keller Mona L. , Pahn Matthias
Published: February 2021

This study investigates a test concept to derive a reliable long-term strength estimation of GFRP bars in concrete environment. Using the time to failure method, test results of straight GFRP bars with different diameters were compared. To represent closely the in service-conditions of concrete structures, the examined bars were subjected to a saturated alkaline concrete environment as well as to a specified stress level till failure occurs. Thus, the experimental setup combines an alkaline resistance and creep rupture tests into one comprehensive testing. By using temperature effects as an accelerating factor, reasonable test durations were enabled. The obtained time to failure line were determined in order to extrapolate the characteristic values of the long-term strength for a service life up to 100 years. As main outcome, the study verify that the examined time to failure is affected by the bar diameter to a negligibly small extent.
Durability of glass FRP reinforcing bars: a state of the art
Authors: D'Antino Tommaso , Pisani Marco A.
Published: February 2021

Glass fiber reinforced polymer (GFRP) bars represent a valid solution for internal reinforcement of concrete elements. With respect to steel reinforcing bars, GFRP bars have a good resistance to corrosion and a high tensile strength. However, durability of GFRP bars is still an open issue and design guidelines and recommendations provide environmental and long-term reduction factors that strongly limit the tensile stress in the bar. In this paper, a large database of GFRP reinforcing bars exposed to different environmental conditions with and without the application of a sustained load and subjected to tensile testing was collected from the literature. The variation of the bar tensile strength with respect to different exposure conditions, namely hot dry and humid air, different alkali environments, and salt solutions with various concentrations, was analyzed and discussed. Furthermore, the effect of sustained stress on the bar tensile strength was studied. A statistical analysis based on the design by testing approach provided by EN 1990 was performed on the results collected to calibrate characteristics and design values of the product between environmental and long-term reduction factors.
Earthquake-induced soil liquefaction risk: macrozonation of the European territory taking into account exposure
Authors: Lai Carlo G. , Conca Daniele , Meisina Claudia , Bonì Roberta , Bozzoni Francesca
Published: February 2021

Among natural hazards, earthquakes claim a large number of casualties and economical losses each year around the globe. Excessive deformations of ground surface caused by earthquakes are of great concern in civil engineering, human lives and the environment. Such ground deformations are often associated with a phenomenon of soil instability called earthquake-induced soil liquefaction. Earthquake induced liquefaction disasters at a continental scale are currently addressed within the European research project LIQUEFACT. The University of Pavia (UNIPV) and the European Centre for Training and Research in Earthquake Engineering (EUCENTRE) are currently in charge for the definition of a European liquefaction risk map in the European territory (macrozonation). It is worth noting that liquefaction is a local phenomenon, thus the macrozonation of liquefaction risk at a continental scale is a challenge. This paper presents the preliminary deliverables of this activity, i.e. the maps for the European territory of liquefaction risk, computed by convolving soil susceptibility, expected seismic hazard and exposure.
Electrical Resistivity of Sustainable Fiber Reinforced Concretes for Smart Marine Structures
Authors: Pereira Isabel , Pereira Eduardo B. , Miranda Tiago
Published: February 2021

Self-monitoring structural materials have recently raised renovated attention due to their potential to enable continuous low-cost monitoring of next-generation smart-structures. This characteristic is particularly important in harsh environments such as highly energetic marine coastal areas, where structural damage due to excessive loading is frequent and very impactful in the performance of structures. In the context this research a sustainable fiber reinforced conductive concrete was developed and studied, with the aim of enabling the future development of self-sensing structural materials and systems for marine harsh environments. The variation of the electrical resistivity with curing time, as well as the compressive loadversusdisplacement responses were investigated. Results indicated that the self-monitoring is possible with sustainable formulations that lead to reasonably conductive concretes. The experimental results seem to indicate that electrical resistivity can be a good parameter for self-monitoring of concrete structures.
Evaluation of the Sustainability Level in Real Estate Buildings in the City of Lima, Peru
Authors: Regalado E. Marck S. , Santa María D. Edward
Published: February 2021

The research is about the assessment of the sustainability level of residential buildings in the city of Lima (Peru) during the occupancy stage of their life cycle, thus generating a proposal for a national sustainable certification methodology adapted to the real situation of the country (main problems, regulations, standards, among others), which allows the most appropriate improvement plans to be proposed. First, the diagnosis of the sustainability characteristics that need to be assessed in buildings in Lima is made. Then, the assessment and scoring method of a situation with such characteristics is presented, which shall be part of the sustainable certification proposal called GREEN UNI. Finally, the certification is applied to a sample of 20 buildings in different areas of Lima, thus recognizing the sustainable situation of buildings in the city.
Fatigue accumulation comparison of simulated traffic flow and design loads
Authors: Lunabba Torsten , Ranta Milla , Julku Kimmo , Lilja Heikki
Published: February 2021

The authors present a fatigue load analysis parallel to their previous studies on simulated site- specific traffic flow and its comparison to static design load models (IABSE, Stockholm 2016, Lunabba et.al.) and fatigue load models (IABSE, Copenhagen, 2018, Lunabba et.al). This research paper expands the previous study to fatigue accumulation analysis of bridges with varying span lengths and transversal stiffness and presents a method where a typical site-specific traffic flow can be compared to Eurocode design load models for fatigue assessment. The accumulated fatigue damage (for typical material dependent SN-curves) of simulated traffic was firstly compared to the characteristic static load model LM1 and secondly to accumulated fatigue damage caused by design fatigue load models FLM1 and FLM3. The study was conducted to one, two and three span bridges having variable span lengths and transversal stiffness characteristics. The study took into account the differences of the load placement (according to Eurocode design loads are placed on the notional lane, but simulated load is placed on the real traffic lanes of the bridge). The study gives guidance to national authorities to pinpoint the most vulnerable bridge types in the bridge stock and the bridges sensitivity to frequent heavy special transportations. In addition, important information about the behaviour and functionality of Eurocode’s fatigue design approach is gained.
Finansparken Bjergsted: an innovative timber-framed office building
Authors: Rando Mario , Mo Gaute , Overton Katie , Ibáñez Fernando , Sánchez-Solís Manuel
Published: February 2021

Finansparken Bjergsted is an office building currently under construction in Stavanger, Norway, for SR-Bank. The structural system above ground level uses timber as the principal load bearing elements (a natural, renewable and readily available local material). Floors are cross-laminated timber (CLT) panels supported by glued laminated timber (GL) beams and columns. For strength and complex geometrical requirements, laminated veneer lumber (LVL) made of beech is also used. The three basement levels and the four communications and services cores are of reinforced concrete. Mass timber structural elements are engineered for strength and are prefabricated with strict tolerances for a rapid construction process using mainly direct contact timber connections, without metal fasteners. The beams are shaped and fabricated with openings to suit both the architectural aesthetics and services requirements by means of a fully integrated BIM system.
Finite Element Modelling of FRP – Strengthened Structural Elements
Authors: Zhelyazov Todor
Published: February 2021

Numerical aspects of the analysis of structural elements strengthened with FRP reinforcement are discussed in this contribution. Constitutive laws are defined on the meso – scale for the materials involved (steel, concrete, FRP).

The evolutions of experimentally observable parameters of FRP-strengthened concrete elements loaded in flexure are obtained by finite element analysis. Numerical results are compared to experimental data.

The employed numerical strategy consists in defining a damage-based constitutive law for concrete. A beneficial outcome of the implementation of such constitutive relation is the possibility to monitor the damage evolution for a given period of exploitation. Since the remaining structural life can be assessed in this way, monitoring of damage accumulation appears as a prerequisite for an accurate and efficient design of the reinforcement.
Functionally graded concrete elements composed of vertical layers of different mixes
Authors: Torelli Giacomo , Lees Janet M.
Published: February 2021

The industrial production of cement is currently responsible for 5-7% of global CO2 emissions. The manufacture of functionally graded concrete structures, where the use of material is optimized by varying the material composition over the volume, opens up vast opportunities to reduce the use of cement. In functionally graded concrete, horizontal gradation can be achieved by casting vertical layers having homogeneous properties. However, a major problem with this kind of application is the control of the fresh state deformations. This study investigates the fresh state stability of concrete prisms that consist of two vertical layers of different mixes. Experiments are performed to invoke stable or unstable behaviour. The results show that, for a given geometry, a relationship between the material parameters and system stability exists.
Guidelines and codes for liquefaction mitigation by ground improvement
Authors: Modoni Giuseppe , Croce Paolo , Proia Roberta , Spacagna Rose Line
Published: February 2021

Ground improvement has become one of the most effective tools of geotechnical engineering, being adopted for an always larger variety of civil engineering applications. To reduce the role of subjective choices of operators, the use of different techniques tends to be codified by specific guidelines. In the European Union there is an ongoing effort to standardize execution and design within codes continuously reviewed by designated committees. A widespread and systematic standardisation on the ground improvement as a mean to mitigate the effects of liquefaction on buildings and infrastructures is missing. The paper presents and overview of traditional and new ground improvement technologies suitable for this application. The methods are firstly classified by considering their effects on the ground (e.g. densification, stabilization, drainage, desaturation, etc.). Design principles are then outlined for new or pre-existing buildings and infrastructures, considering the ongoing review process of the design Eurocodes.
Impact propagation effects along reinforced concrete beams
Authors: de Ulzurrun Gonzalo S. D. , Zanuy Carlos , Johansson Morgan , Rempling Rasmus
Published: February 2021

This paper studies the time-dependent structural behaviour of concrete beams subjected to impact loading. Drop-weight tests have been carried out in 1180 x 100 x 100 mm longitudinally reinforced concrete beams. Experimental results have been obtained by combing a high speed camera with two-dimensional digital image correlation. The analysis focused on the dynamic internal forces distribution and wave propagation. Flexural moments and, especially, shear forces were greater than their static strengths, confirming the strain-rate dependence of both failure mechanisms and clarifying the sensitivity of concrete to develop brittle failure. Wave propagation analysis showed a variable velocity, decreasing as the slenderness of the effective span increased.
Incorporating Flexibility in Life-cycle Analysis of Infrastructure
Authors: Torres Rincón Samuel , Sánchez Silva Mauricio , Villarraga Daniel F.
Published: February 2021

Infrastructure systems are constantly exposed to uncertain demands from the environment, the users and the stakeholders. These uncertainties may negatively affect the life cycle performance and the sustainability of the structure. The traditional robust design approaches may be insufficient to face these changing conditions without compromising the system’s financial sustainability. As an alternative, system managers can implement a design approach based on the concept of flexibility. Designing for flexibility confers to the structure the ability to change when the external conditions evolve, potentially improving the life cycle performance. Unfortunately, the concept seems to be underdeveloped in the infrastructure systems literature; there is no consensus in the academic community regarding how to define flexibility and how to measure it. In this work, this situation is addressed with the formulation of an original flexibility index for a system design variable, based on the available adaptation range and the unitary adaptation cost. The proposed index is tested using a hospital building as practical example to demonstrate its applicability, and highlight some benefits provided by the implementation of flexibility in the structure’s financial performance.
Influence of local scour at multiple piers on the vibration characteristics of a bridge under seismic excitation
Authors: Anžlin Andrej , Prendergast Luke J.
Published: February 2021

Bridges founded in water can be prone to scour erosion, an effect which alters the dynamic properties of the bridge. In seismic regions, bridges are prone to excitation from earthquakes, which can be damaging to the structures. These two hazards, while independent from one another, can alter how each affects a bridge in the sense that an earthquake may pose a more serious effect on a scoured bridge than on the unscoured structure. The magnitude and location of a scour hole affecting a structure can alter the seismic bridge response to varying degrees. In this paper, a finite-element model of a multi- span bridge is created using OpenSees, and some preliminary results of a numerical investigation into scour at multiple locations and the resulting impact on the seismic behavior is reported. The bridge is subjected to ground motion considering several defined scour conditions, where scour is modelled as the incremental increase in length of a given pier. The influence of scour depth and location on the internal shear forces, displacement and accelerations of the structure are studied with a view to ascertaining critical damage combinations.
Infrastructure Public Private Partnership Implementation and Risk Management – Lessons from Albanian Approach
Authors: Keçi Julinda
Published: February 2021

Public Private Partnerships (PPPs) are being frequently used today to offer large infrastructure projects in the Western Balkan. In a small country like Albania, today there are more than 170 infrastructure PPPs, counted mainly in hydropower and road sector. Their application aims to provide funds to reduce the existing gap between the available budget and public expenses, expand investments in infrastructure as a major drive of economic development, improve the quality of services and the efficiency of project delivery, optimize resource utilization, commercial valuation of public assets and achieve optimal risk allocation.

The purpose of this paper is to study and review the application of PPPs for large infrastructure projects, highlighting lessons learnt from Albanian approach. The focus will be on implementation framework and risk management. The study uses a combined approach: questionnaire survey- targeting the applied PPPs in Albania- to identify the main risks encountered and their allocation preferences, and case study approach to investigate the phenomena within its real-life context. Three case studies are chosen: Mother Teresa Airport Terminal, as a representative of infrastructure project, in its operation phase; ASHTA HPP, as representative of a PPP in hydro energy, in its operation phase; Devolli HPP, as a hydropower concession, in its construction phase. Observations and documentation review-aimed to identify the phases and procedures, and semi structure interviews- aimed to identify the main risks, their allocation and treatment, are used.

The findings of the study are organized in three parts: First, the qualitative study identified the mostly used PPPs, their main risks and allocation preferences. Secondly, the case study review and third, lessons learned for future applications, such as the need for lifecycle value for money analysis on procurement methods, unsolicited proposals implications, lack of negotiation phase contractual cost implication, lack of social assessment requirement.
Inspection and Short, Medium and Long-Term Monitoring of a Historic Brazilian Bridge
Authors: Colombo Alberto B. , Freitas Ronaldo , Neto Alfredo P. C. , Hune Rafael P. , Bittencourt Túlio N.
Published: February 2021

The findings from the inspection and short, medium and long-term monitoring of the historic Brazilian bridge Dom Pedro II are presented in this paper. This puddled iron truss bridge, which was commissioned in 1885, was originally designed for railway traffic and was adapted in the last decades to support both railway and highway traffic. In recent years, this bridge has undergone several maintenance programs and is currently undergoing a considerable rehabilitation process. Field inspection and short-term monitoring was carried out in 2012 and recently, in 2017, a medium-term monitoring system was put in to place. During the rehabilitation process field monitoring techniques which use spot-weldable thermistors and strain-gauges are being used which allow for the monitoring of the load redistribution process. A long-term monitoring system is also being put into place following the rehabilitation of each span. This system will enable the online monitoring of strains, rotations, displacement, vibrations, and wheel loads from the trains. The long-term monitoring is expected to be carried out for at least a three- year period and will enable the bridge owners to observe the effects of the rehabilitation process. A description of the most recent findings and the technology and methodologies that were used in this process is presented as well.
Inspection of Existing Bridges – Moving on from condition rating
Authors: Hajdin Rade , Casas Joan R. , Campos e Matos José
Published: February 2021

It is widely accepted that safety and serviceability are primary concerns in bridge design. However, for the most of bridges’ service life, these concerns are addressed indirectly by a qualitative meas- ure, defined herein as condition rating, which is based upon observable damages recorded during inspections. Condition rating is at best, only loosely correlated to safety and serviceability. It would be more reasonable to address safety and serviceability in an inspection process directly, using the information on bridge performance obtained during the design and construction.

To address this issue, the reliability was chosen as a Key Performance Indicators (KPI) for existing bridges and a novel practical solution is proposed. It is based on survey of observation types (visible defects, measurements, etc.) used in Europe, which were examined with regard to their potential impact on reliability regarding safety and serviceability. The impact of these observations on relia- bility is also dependent on their type, location and intensity/extent as well as on bridge structural systems. The paper presents a methodology to assess reliability, which heavily relies on data from design and construction phase. It also proposes a set of data elaborated in design and/or construc- tion phase that need to enter current bridge data bases to allow a rough reliability assessment of existing bridges.
Intelligent, sustainable and integrated system of management of structures
Authors: Royes Miquel Morata , Garcia Gil Lívia , Pérez Caldentey Alejandro , Gimenez Vila Javier , Capelastegui Lasso Abel , Muñoz Navascues Óscar
Published: February 2021

In Spain, the national road network comprises over 17.000 bridges and viaducts, besides those managed by local and regional administrations. Many of these structures are very old; however, it was not until the 90s of the XX century that maintenance awareness rose among the society. Inspections are currently carried out visually, on a manual basis, implying low effectiveness and high costs.

To tackle these issues the SISGES project was conceived and aimed at developing a smart management system capable of making rational decisions regarding the maintenance and repair of existing structures. The methodology that has been followed to achieve this goal is to study the current available technologies, develop a data management structure, develop a monitoring system for each structure, create a structural model while considering interoperability with BIM and finally, develop a management application/software to be used for both technical profile users and general managers.

The SISGES platform comprises remote inspection technology, which reduces the inspection times and costs while increasing workers’ safety; continuous monitoring technologies, registering displacements, vibrations, temperature and humidity; scanning technologies to create three- dimensional models of the structures and BIM technologies to assign each element with an attribute.

Overall, this makes an innovative and integrated infrastructure management system in line with available technologies and capabilities while maximizing the efficiency of inspection and monitoring for current and future bridges and viaducts.
Life Cycle Cost Analysis of Two Structural Systems for Buildings
Authors: Wang Hongyang , Du Guangli , Hou Hetao , Buch-Hansen Thomas Cornelius , Wang Chenglei
Published: February 2021

This paper compares the life cycle cost of two commonly used structural systems for buildings: the pre-fabricated steel structural system and the cast-in-situ concrete frame structural system. The case study of the No.2 experimental primary school building, located in Jiyang County in China, is presented as an illustrative example. The building is designed for six stories with 20.1 m in height and 9713.85 m2 construction area, considering 50 years life-span and 7 degrees seismic intensity scale. Ten design solutions are proposed for this case study covering these two types of structural systems, with the combination of different types of interior/exterior walls and slabs. A life cycle cost analysis is performed to evaluate the economic performance among these design alternatives, including the initial cost, construction cost, maintenance cost, removal cost and residual value. The result concludes that the pre-fabricated steel frame structural system has a significant advantage over the cast-in-situ concrete frame structural system from the total life cycle cost perspective.
Lifecycle Quality Control of New Locks in a Public Private Partnership setup
Authors: Zanen Paul , Lambert Thijs
Published: February 2021

A Public Private Partnership (PPP) setup underlines and increases focus on lifecycle quality and lifecycle quality control. The new lock PPP’s in The Netherlands provide unique incentives that ensure the following day to day practice:

Implementation of a lifecycle performance-based design with a focus on availability- and reliability engineering.

Using KPI’s and real-time verification on technical components enhances requirements compliance.

Predictive maintenance through continuous condition based monitoring.

Rigorous quality management based on ISO 15288, 15504 and 55001 to control life cycle quality.

Increasing long term client benefits in life cycle costing.
Management of risk of exceeding design loads for reinforced concrete highway bridges
Authors: Vasilyev Alexander I.
Published: February 2021

The following topic is analyzed in this study: risks of exceeding the required levels of load capacity of reinforced concrete bridge superstructures due to the variability of operational traffic loads on bridges. Decrease of load capacity during operation is mainly due to the corrosion wear of the working reinforcement. The following types of risks of loss or decrease of load capacity are considered:

undesirable – when restriction of the traffic on the bridge or reducing its durability is required; unacceptable – when termination of traffic on the bridge is necessary

critical - the danger of a catastrophic collapse with possible human victims.

During the entire period of operation, the exceedance probability of operating loads should not be lower than the one of the design load at the final stage of the bridge service.
Models for Evaluating Shear Strength on Members with Circular Cross Section
Authors: Turmo José , Ramos Gonzalo , Aparicio Ángel C.
Published: February 2021

Solid circular columns are often used as structural supports in bridges, buildings and foundations due to their simplicity of construction and because their strength is similar in any direction. This deem them very suitable to resist wind and seismic loads. Hollow core circular concrete members are much less structurally used than solid circular cross sections. However, these can be found in concrete chimneys, concrete pipes and elevated water tanks, as well as in large bridge columns and offshore platforms. Codes do not usually propose specific formulations for evaluating the shear strength of such structural types or if they do, they do so in a very simplified manner.

Hence, an analytical model for evaluating the contribution of the transverse reinforcement in concrete members of solid and hollow circular cross section is presented in this paper. After a thorough bibliographic research on the previous studies on the matter, the shortage of work accomplished on the topic has been assessed and the unsolved problems identified. A formula for evaluating the shear transferred by spiral reinforcement in solid members is presented. A formula for the calculation of hollow core circular columns with both vertical and spiral reinforcement is also deduced. Assumptions made for the calculation of this formulation have been deduced theoretically and then checked empirically. Hence, shear tests on circular hollow core specimens will be also presented.
Monitoring of pedestrian patterns of an office floor under normal walking activity
Authors: Muhammad Zandy O. , Reynolds Paul
Published: February 2021

Innovative designs and development of advanced construction techniques enabling efficient use of materials have resulted in modern building floors that are characterised by longer spans, lighter weight and lower inherent damping. In the particular case of office floors, current design trends are for fewer internal partition walls and more open plan layouts. Therefore, such floors are more susceptible to excessive vibrations originating mainly from pedestrians traversing the floors with random patterns of walking.

Technological advances in tracking human locations, well-known in computer sciences, by means of in-built video cameras integrated with vision tracking software are rapidly increasing. Yet their potential implementations have not been extended significantly to monitor and track patterns of pedestrians in civil engineering structures, in particular floors. Research of the use of these techniques and pertinent experimental exercises is lagging. This paper provides the results of video monitoring of the occupant activities of a typical office floor under normal use. It is obvious that floors accommodate multi-pedestrians with walking patterns that are somewhat random. Hence, tracking and monitoring of operational floors accompanied by the vibration response measurements give an insight to the actual patterns of walking and thus corresponding in-service vibration responses. It is recognized that distribution of walking patterns with measured vibration responses help capture realistic vibration levels, particularly when combined with statistical methods of vibration serviceability assessment.
Multi-criteria decision analysis methods to support sustainable infrastructure construction
Authors: Ek Kristine , Mathern Alexandre , Rempling Rasmus , Rosén Lars , Claeson-Jonsson Christina , Brinkhoff Petra , Norin Malin
Published: February 2021

The construction of infrastructure projects represents a large sustainability impact, both positive and negative. Increased positive and reduced negative impacts can be achieved through better design and planning of the construction. To make more sustainable choices, well-defined predictive sustainability assessment methods are required. Multi-criteria decision analysis (MCDA) is a well- suited method for predictive sustainability assessment. This paper evaluates two MCDA methods for sustainability assessment of infrastructure construction and exemplifies their application with two case studies. The aim of this paper is to discuss if the methods are suitable for identifying the most sustainable alternative during the procurement process of an infrastructure project. It is recommended that MCDA methods are further developed to comply with the recently published EN standard on sustainability assessment of civil engineering works.
Necessity and Invention: Leveraging a Megaproject to Advance the use of Computational Design
Authors: Kostura Zak , Clark Matthew C. J. , Olson James R.
Published: February 2021

The roof of the New International Airport for Mexico City is a lightweight steel shell structure and an architectural centerpiece of the new 4,432 hectare greenfield airport development. Visually exposed and structurally independent from the building beneath, it supports a 500,000m2 envelope that reaches a peak height of 45m above ground level and maximum span-to-depth ratio of nearly 60:1. While it is comprised of several subassemblies, including a 2-layer tetrahedral ball-node space frame and single-layer welded CHS shells, the roof was designed and detailed with the overt intent of achieving seamless visual continuity across the entire system. It is a mile long, nearly half a mile wide and is achieved with no movement joints. This paper focuses on the design approach, structural hazards and technical solutions for addressing global buckling and validity of welded CHS connections throughout the system.
Nonlinear Static Analysis by Finite Elements of a Fujian Hakka Tulou
Authors: Briseghella Bruno , Colasanti Valeria , Fenu Luigi , Nuti Camillo , Spacone Enrico , Varum Humberto
Published: February 2021

Hakka Tulous are massive circular earth constructions of the Fujian Province, China, included in the UNESCO World Heritage list. They are subjected to earthquakes of medium magnitude, but their response to the seismic action is not yet investigated in depth. The seismic response of Fujian Tulous was herein investigated through pushover analysis modelling the Tulou structure by finite elements. Although the Tulou is a big construction with a circular earth wall of about fifty meters in diameter, a micromechanical approach was used to model the earth nonlinear behaviour. Even if no binder is added to the earthen material, the Concrete Damaged Plasticity model can be adopted and has shown to be effective in modelling its nonlinear behaviour, as well as the nonlinear response of the Tulou earth wall. Performing pushover analysis of a big earth structure using a micromechanical approach seems to give reliable results, that must be proved by future research.
Numerical assessment of shear connection for steel and concrete composite floors
Authors: Silva Talita L. , Valente Isabel B.
Published: February 2021

The use of steel and concrete in composite floors contributes to more sustainable constructions, because they become lighter, the overall weight of the building is reduced and the steel components can act as formwork. Composite flooring solutions are usually composed by a composite concrete slab and a steel profile. This system is mechanically successful if shear connectors are used, as they guarantee the transmission of shear stresses between the steel and the concrete components. This investigation proposes the use of a connection system, composed by a ribbed steel plate welded to the profile and is embedded into the concrete slab after the concreting phase. The study was carried out through numerical modelling to represent a group of push-out tests previously performed. From the comparison with the experimental results, it was possible to calibrate the numerical models and developed parametric analyses.
Numerical modeling of a resilient hinge (RH) for accelerated bridge constructions
Authors: Katakalos Konstantinos , Kagioglou Panagiota , Mitoulis Stergios
Published: February 2021

The present paper focuses on the advanced numerical modeling of a novel resilient hinge (RH), with emphasis on the connection between the foundation and the bridge pier. The design philosophy of dynamic resistant structures (such as bridges) requires the imposed energy to be dissipated in the hinges of the structure and let the remain elements with no damages. The investigated Resilient Hinge (RH) was proposed by Mitoulis et al. in 2016 and is further developed in this paper through parametric numerical simulations utilizing the 3D FE software Abaqus. The RH is a novel substructure that mitigates the imposed energy through the yielding of easily replaceable steel bars, thus offering rapid restoration times. It is designed to have re-centering capabilities because several steel bars remain primarily elastic, so they return to their initial position. The investigated variables are the type of material, the roughness of the contact surface, the diameter of the bars and the type of connection between the different parts of the RH. Stress analysis of the obtained results occurred in a way to quantify the problem and discover the weak regions of the RH. Finally, detailed design suggestions for the RH are provided.
On the Advantages in Sustainability of Structural Concrete Bubbled Deck Slabs
Authors: Oukaili Nazar , Merie Hammad
Published: February 2021

One of the significant methods, which reduce environmental damage, is by using the sustainable elements into construction activities. Bubbled deck is a slab system in which the ineffective concrete in the centre of the section is replaced by HDPE hollow spheres which are produced from waste plastic materials. It offers sustainable structural system due to decreasing (35%) of the self- weight and, therefore, the use and transport of less construction materials. In this study an investigation was carried out on (33) bubbled deck slabs of different dimensions and different sphere diameters, where part of specimens was with openings. The main objective of the study is to determine the impact parameters on increasing the sustainability effect through the input raw materials, energy consumption, and CO2 emissions for the bubbled deck slabs in comparison to solid slabs. Results of the study showed that the reduction of raw materials for bubbled deck slabs led to reduce the energy consumption and CO2 emission by (12%-40%).
Portal and cantilever sign/signal gantries – Inspection and retrofitting
Authors: Mendonça Tiago , Brito Vítor , Almeida Manuel
Published: February 2021

This paper presents an experimental work about the condition and maintenance ratings of portal and cantilever sign gantries in Portugal, in which an extensive inspection campaign (about 1500 structures) was carried out. According to the results obtained, approximately 35% of the sign structures present insufficient condition rating, requiring priority repair works. The critical anomalies registered were lack of tightening/absence of connection elements, incorrect geometry of connection system and structural collapse of steel plates and profiles. Additionally, an inventory campaign was carried out, allowing to perform a structural design verification of approximately 80% of the inspected structures. Based on the structural analysis performed, a significant part of the existing portal and cantilever frames present structural strengthening or replacement needs and, consequently, these of structures require monitoring actions.
Probabilistic Design for Deteriorating Reinforced Concrete Structures with Time-Variant Finite Element Analysis
Authors: Kouta Tsuyoshi , Bucher Christian
Published: February 2021

In this study, a probabilistic design method using time-variant three-dimensional finite element (FE) analysis is presented to predict the structural reliability of deteriorating reinforced concrete (RC) structures due to chloride-induced corrosion. First, models of probabilistic corrosion due to chloride-induced corrosion are briefly reviewed. Then, FE modeling methods for corroded RC structures are presented, followed by validation with reference to experimental tests. In the methods, concrete and reinforcing steels are separately modeled, and the degradation in mechanical behavior of both components is considered. Finally, as an illustrative case study for the proposed FE analysis, the time-variant structural safety of a box-girder bridge is calculated over its lifetime of 50 yrs. The results of this study indicate that the proposed methods can be used to estimate the long-term structural safety of deteriorating RC structures.
Probabilistic Finite Element Model Updating of Civil Engineering Structures: A Comparative Study
Authors: Jiménez Alonso Javier F. , Hudson Emma J. , Pavic Aleksandar , Sáez Andrés
Published: February 2021

Finite element (FE) model updating of civil engineering structures is usually performed under the modal domain. According to this approach, the value of the main physical parameters of the structure is modified in order to reduce the relative differences between the experimental and numerical modal parameters of the structure. To date, two methods are widely used to perform the FE model updating: (i) the maximum likelihood method and (ii) the Bayesian method. The second method is usually implemented via sampling methods. Thus, the FE model updating consists in determining an efficient sampling of each considered physical parameter of the model. Herein, two sampling techniques, the Metropolis-Hastings (M-H) algorithm and the Slice Sampling (SS) algorithm, are compared when they are implemented for the FE model updating of a laboratory steel footbridge.
Quality control plan for road bridges – overview of COST Action TU1406 WG3 final report
Authors: Kušar Matej , Linneberg Poul , Amado Joao , Mašović Snežana , Tanasić Nikola , Hajdin Rade
Published: February 2021

The main objective of the COST Action TU1406 is to develop a guideline for the establishment of Quality Control plans for roadway bridges. The guideline is based on conclusions of Working groups 1 and 2 of the Action and is further developed with the contributions and findings of members of Working group 3. The paper presents the overview of the developed framework, where gradual damage processes as well as sudden events are being addressed in evaluation of Key Performance Indicators. The proposed framework relies on data from design and construction phase, as well as from results from visual inspections that are used for an assessment of safety and serviceability - the primary concerns of bridge managers. Special attention is aimed at possible Failure modes and related bridge Vulnerable zones. These are, for instance high moment regions, high shear regions and constructions joints, but can also be zones of bridge conceptual weaknesses. Since there are differences in design and materials for various bridge types, the suitability of the framework is tested separately for girder/frame bridges and arch bridges. Due to the specifics of sudden events, the application of the framework is given separately from gradual damage processes. Emphasis is given on flooding and scour as these are the most common culprits of bridge failures. The steps in the implementation of the framework are briefly shown and an illustrative example is presented.
Quality specifications and performance indicators for road bridges in Europe
Authors: Strauss Alfred , Campos e Matos José , Casas Joan R. , Fernandes Sérgio
Published: February 2021

Across Europe, multiple management systems were developed with the aim of managing roadway bridges in an efficient manner. Although being generically similar, the condition assessment process, based in the assessment of performance indicators which are compared with performance goals in order to evaluate the accomplishment of established quality control plans, can be identified as one difference among them. This leads to the existence of multiple different methodologies for assessing the bridge condition, and consequently to a considerable variation in roadway bridges quality. COST Action TU1406 aims to achieve the European economic and societal needs by standardizing the condition assessment and maintenance level of roadway bridges. For such purpose it would be required the establishment of specific recommendations for the quantification of performance indicators, the definition of standardized performance goals and, finally, the development of a guideline for establishing quality control plans.
Railway Track Asset Management, from long-term vision to completion
Authors: Grossinho Andreia
Published: February 2021

Infraestruturas de Portugal, S.A. (IP) is one of the major physical asset managers in Portugal, including the railway track assets of the National Railway Network. The current railway track technologies installed in the network range from the most modern solutions, which allow higher performances against ever more demanding service levels, to others not so recent although still adequate for the operation characteristics of certain lines. Being a network in evolution for over 150 years, occasionally there are some network sections where the installed technology is still the original one. The network comprises distinct railway track superstructure solutions, with very different performance requirements, variable degradation cycles and a multitude of maintenance intervention needs. In this context, and bearing in mind the high volume of maintenance and renewal needs, the management of railway track assets is a major challenge for IP.
Rate-Dependency Study of Reinforced Concrete Piers with Cyclic Loading Tests, Hybrid Simulations, and Shake Table Testing
Authors: Park Minseok , Kim Chul-Young , Choi Sunah , Chae Yunbyeong
Published: February 2021

Dynamic response of structures can be evaluated experimentally by conducting various tests such as cyclic loading test, hybrid simulation, and shake table testing. It has been known that concrete materials are rate-dependent. However, the rate-dependency of reinforced concrete (RC) structures has not been sufficiently studied, especially under earthquake loads with their actual loading rates. For this reason, it has been believed that the response of RC structures is not so sensitive to loading rate expected from earthquake loads. In this study, the rate-dependent behaviors of RC piers are investigated and compared by conducting cyclic loading test, slow hybrid test(SHT), real-time hybrid test(RTHT), and shake table testing(STT). A small-scale rectangular sectioned RC piers are manufactured and subjected to various loads with different loading rates, where it shows that the strength, energy dissipation capacity, and structural response of the RC piers can be substantially affected by loading rate.
Reconstruction of Wangduephodrang Dzong, Bhutan – protecting the heritage and improving earthquake resilience
Authors: Galmarini Andreas , Dorji Nagtsho
Published: February 2021

Wangduephodrang Dzong, an important heritage structure of Bhutan burned to ground. This paper describes the measures developed to reconstruct the Dzong using traditional stone masonry and mud mortar with improved resilience against earthquakes. Intensive discussions with stakeholders lead to minimzed interventions.
Reliability Evaluation of Structural Safety Factor Using a Global Resistance Approach
Authors: Santos Sergio , Monteiro Junior Marcio Tacques R. , Martha Luiz Fernando , Interlandi Claudia
Published: February 2021

This paper presents a discussion on different ways of assessing the safety of concrete structures applying Reliability Analyses. The usual design approach based on the Ultimate Limit States (ULS) is confronted with the Global Resistance Format, as defined infib Model Code 2010. The Global Format considers the several uncertainties present in the structural behaviour through a pre-defined limit state in which one or more loading variables are increased by aλfactor, until a collapse situation is attained. In this evaluation, the variables related to the actions and to the resistances are taken with their average value. The obtained values for theλfactor shall be compatible, in the safety point-of- view, with the β reliability factors corresponding to the required safety levels. A conventional building is analyzed, and the obtained reliability factors corresponding to the two approaches are presented. It is shown that the application of the Global Resistance Format can lead to more economical structures.
Reliability of a Bridge Subjected a Multi-Hazard: Scour and Earthquakes
Authors: Olvera Ramírez Berenice A. , Olmos Bertha , Jara José Manuel
Published: February 2021

Bridges are important structures for being part of the economic-social system of a country, for that is important to quantify their probability of damage. They are important structures for being part of the economic-social system of a country, for that is important to quantify their probability of damage. The objective of this work is to determine the failure probability of a real bridge accounting for the multi-hazard by estimating fragility curves where the capacity is assessed with static nonlinear analyses, and the hydraulic and seismic demands are characterized with probabilistic models. The bridge’s probability of failure is calculated using MonteCarlo simulations.
Resilient System for a Conditioned Predictive Maintenance of Railway Infrastructure
Authors: Soley Gisela , Royes Miquel Morata , Manzo Nahuel , Fontserè Valentí , Peset Joan
Published: February 2021

RESILTRACK, “Smart and Resilient System for a Conditioned Predictive Maintenance of Railway Infrastructure”, is a 4-year project co-funded by the Centre for the Development of Industrial Technology (CDTI) in Spain. RESILTRACK brings together 6 Spanish partners (COMSA, Retevisión, Telice, Cemosa, Magtel and Estudios GIS) and 4 research and technological institutions (CIMNE, Tecnalia, Leitat and University of Málaga) to work on the design of a system which provides real time information of the infrastructure state and how it is affected by climatic effects. Data will be obtained by a robust, integral and autonomous monitoring of the railway infrastructure, and it will be analyzed by predictive simulations through DEM-FEM models. Finally, the concepts will be integrated through a BIM tool to facilitate decision making.