bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Structures and Bridges built with the CL Steel-concrete Connection
Authors: Berthellemy Jacques , Seidl Günter , Lorenc Wojciech
Published: February 2021

The design principle of the CL connection between steel and concrete is well established in Europe. The CL shape composite dowel between steel and concrete was used to realize economic and esthetic solutions for flyover bridges crossing motorways under traffic without intermediate piers with for example the precast composite beams (Preco-Beam or VFT) construction method.

The reconstruction of the bridge of Elblag in Poland enhances the construction method. The cutting line of the rolled section implements a varying height of the steel web for the midfield and near the support. The details of the Elblag viaduct are presented. Also economic aspects is discussed.

The viaduct over the river Elster next to Osendorf is the first bridge project using the CL connection and the Preco-Beam construction method in Germany (VFT) with a hot-dip galvanized steel structure. The external reinforcement made out of halved rolled sections contains only a small ratio of residual stresses. The steel girders are easy to handle with a length up to 16 m. The Osendorf bridge demonstrates the economic feasibility of the hot-dip galvanizing due to quality, costs, maintenance.

Two bridges carrying acoustic walls along the motorway in Marseille were in France the first projects realized with the CL connection. Each structure has to carry a 6,50m high wall that has to cross a 22 meter span near the existing motorway bridge but without any support on him. The location of these structures is exposed to important wind solicitations. The fatigue due to the wind turbulences was considered to design these bridges. The use of the CL connection could simplify the anchorage of the wind forces on the concrete support, in comparison with more conventional solutions.
Form Optimized CFRP Reinforced and Post-tensioned Integral Concrete Bridge using Precast Girders
Authors: Schlaich Mike , Apitz Andreas , Goldack Arndt
Published: February 2021

Numerous bridges in Germany are currently reaching the end of their lifetime. This is a chance for new bridge types and materials to be investigated. Concrete bridges with CFRP reinforcement – both prestressed and non-prestressed – have the potential to meet the current demands in terms of durability, robustness and economic viability. As part of the joint research project C³ - Carbon Concrete Composite, the Chair of Conceptual and Structural Design at the Technische Universität Berlin (TU Berlin) is conducting research on prestressed CFRP concrete bridges together with other research institutes and industrial partners. In this paper the conceptual and structural design of a concrete bridge using CFRP prestressed and reinforced precast girders is presented. According to the material characteristics of CFRP and the construction process, an optimized and unusual shape was conceived. As a result, the advantage of CFRP versus steel in terms of corrosion resistance and strength can lead to slender structures and material reduction.
Engineering structures for the CNM HSL
Authors: Zhang Yi , Regallet Dominique , Gillet Philippe , de Boissieu Etienne
Published: February 2021

This paper presents an overview of engineering structures for the Nîmes-Montpellier Bypass (also called CNM, French acronym of Contournement Nîmes-Montpellier), which involves the design, execution and maintenance of the first dual-track, mixed high-speed passenger and freight rail corridor in France. With a total length of 80km, including 20km of connections to existing lines, this bypass includes 183 engineering structures: 12 viaducts, 1 cut-and-cover tunnel and 170 standard engineering structures. Overall, 4 years were necessary to build the CNM HSL, including

2.5 years for civil works and a total of 320,000m3 of concrete, 55,000T of steel reinforcements and 15,250T of steel frames were used. The line was opened at the end of 2017 and the maintenance is guaranteed until 2037 by the public–private partnership contract.
The Vidourle Viaduct
Authors: Zhang Yi , Regallet Dominique , Boireau Sylvain , Charpin Christian
Published: February 2021

The Vidourle Viaduct is an iconic structure on the Nîmes-Montpellier Bypass (Contournement Nîmes-Montpellier or CNM in French), the first dual track, mixed traffic high speed railway line (HSL) in France. The viaduct is 159 metres long and 14.1 metres wide, and consists of one Warren main bridge and two half-through access bridges. The aesthetic features of the viaduct were designed by Alain Spielmann’ architectural office. This paper describes its structural design, structural analyses and construction methods.
Numerical Analysis of Large Amplitude Nonlinear Vibration of High-Speed Train PRC Bridges and Design of Tuned Mass Dampers
Authors: Mustafa Atta E. , Mizutani Tsukasa , Nagayama Tomonori , Di Su
Published: February 2021

In some Prestressed Reinforced Concrete (PRC) girder simply supported bridges of the high-speed train, Shinkansen, resonance-like phenomena were observed; the first natural frequency of the structure, subject to the effect of temperature change, is low as clarified through field measurements, possibly causing the large vibration. In addition, nonlinear behaviors of structures are observed. The nonlinear behavior of the PRC girder bridge is simulated using FE models on ABAQUS and the resonant frequency and the maximum response of the structure are clarified. Tuned Mass Dampers (TMDs) to suppress the vibration are designed considering the response of structure as well as the response of TMDs. The parameters of TMDs, which are set to minimize the response of the structure under the constraint of controlling the response of TMDs within design limits. After design of TMDs, the robustness against possible change in the natural frequency of the structure due to temperature change is also examined.
Design of High-Speed Railway Bridges with Earthquakes
Authors: Cao Yinghong , Ude Todd
Published: February 2021

The California High-Speed Train (CHST) Project is located on the west coast of the United States, which is one of the areas around the Pacific plate that has high earthquake risks. This caused additional challengers in the design of the bridge structures. Generally, the high-speed rail requires rigid structures to satisfy tight limits on deflection and vibration control. But in earthquake areas, flexible and ductile structures are often preferred to resist seismic excitations efficiently. This paper highlights design criteria associated with these conflicting demands and presents some optimal design solutions that best balance these requirements.
Superstructures of the CEVA Railway Stations
Authors: Adam Bernard , Menétrey Philippe
Published: February 2021

An innovative modular construction system is developed to design the superstructures of five railway stations on the new CEVA railway in Geneva, Switzerland. It involves large scale glass bricks façade elements supported by exposed slender steel structures that are integrated in the building envelope. The system adapts to each building particularities and environment to create unity among the five stations in the city. The glass bricks are large scale façade, roofs and floor glazed elements. The steel structure elements are welded built-up box sections with a constant width. Glass bricks and steel structure elements are designed with the same thickness to flash. This innovative modular construction system leads to many challenges in both façade and steel structure design to create a strong visual identity of the CEVA railway which is a “megastructure” composed of multiple bridges, tunnels, cut-and-covers and stations.
Running Safety of a High-Speed Train Through a Multi-Span Bridge under a Non-Uniform Moderate Earthquake
Authors: Choi Dong-Ho , Mu Di
Published: February 2021

The train-track-bridge system is significantly excited, even by a moderate earthquake. Therefore, the running safety of the train under an earthquake should be studied to prevent the derailment during its operation. This work investigates the running safety of a high-speed train moving through a multi-span bridge and excited by a non-uniform moderate earthquake. The track-bridge system is modelled by three-dimensional finite element method. Each train vehicle has 27 degrees-of-freedom and is described by the rigid bodies linked by suspensions. The stationary random track irregularities are generated using the empirical one-sided power spectral density functions. The non-uniform seismic excitations are applied to the bridge piers using the large mass method. The derailment factor and the offload factor is used to evaluate the running safety of the train.
Stay Cable Replacement and Preservation of the Pertuiset Bridge for Strengthening
Authors: Kaczkowski Nicolas , Buchin-Roulie Vanessa , Bouchhima Oussama , Travers Nicolas
Published: February 2021

Pertuiset Bridge, built in the 80’s over the Loire River in Unieux (France), is one span stay cable of 132 meters in length composed of one reverse Y shape pylon. Two layers of 13 stay cables supports the main span, and backstay cables are composed of 2 layers of 10 cables anchored in a counterweight. The deck is composed of two lateral prestressed beams and prestressed cross beams spaced at each 4m, and was built by cantilever erection method. In this project, Freyssinet has proposed a complete portfolio of strengthening technologies such as additional external PT, new micropiles, replacement of stay cables, shotcrete and CFRP. This strengthening allowed to reduce excessive tensile stresses in the deck and therefore allowed the stay cables replacement as well as the removal of traffic limitation of 3,5 tons (30 tons now).
Strengthening an Existing Low-Rise for Conversion to a New Hip Hotel with a Rooftop Swimming Pool, Bangkok
Authors: Buddee Samard
Published: February 2021

An existing low-rise building was constructed in 1996 and then bought in 2006 for conversion into a new hip hotel with a rooftop swimming pool. A reinforced concrete static analysis was performed using relevant computer programs, consideration of codes, the actual reinforcement amounts, as well as concrete core compression values, UPV test results of the concrete properties, and existing structure dimensions. It was found that there were 6 existing columns with insufficient strength. Hence, a structural engineer decided to strengthen these existing columns by using steel jacketing in order to increase their strength and ductility including the improvement of its earthquake-resistance capacity to support all loads. Finally, it was found that the strengthening had been done effectively and proved that the existing columns have sufficient strength. Since its renovation in 2009, the hotel has been in continuous use with no signs of structural deficiencies.
Punching Shear Strength of Concrete Slabs by Overlay of UHPC with Textile Reinforcement
Authors: Hong Sung-Gul , Youm Hyun-Soo , Hong Namhee K.
Published: February 2021

This paper presents the test results on 5 flat slab-column connection specimens with Ultra High Performance Fiber-Reinforced Concrete (UHPFRC) overlay to investigate the retrofitting effect of UHPFRC overlay on the punching shear capacity. The test parameters were the thickness of the UHPFRC overlay and the reinforcement ratio in the overlay. All specimens failed in punching shear mode with softening failure modes. The test results showed the increases in global punching shear resistance up to 82% and structural rigidity by a thin layer of UHPFRC over the reinforced concrete (RC) substrates. Furthermore, the cracking patterns in the composite systems by two failure modes control the ultimate strength: 1) diagonal shear failure in RC section and 2) debonding failure at the interface.
Reinforcement of Felix Houphouët-Boigny bridge in Abidjan
Authors: Picard Ludovic , Descamps Nicolas , Simon Emmanuel , Menuel Frédéric , Gabouge Hamadi , Chambosse Amandine
Published: February 2021

Felix Houphouët-Boigny bridge in Abidjan is a twin double deck bridge (Road up / Rail down), crossing the Ebrié laguna, 372 lm long with 2 x 8 x 46.5 lm spans, built in 1956. Further to the sliding of a layer of sand that induced horizontal efforts, significant cracking occurred on the piles that worsened over time. Moreover, the concrete of the piers has been gradually deteriorated due to the salty laguna environment and the deck has suffered the effects of aging. The solution of reinforcement consists in creating new piles next to the existing ones, which will support “transfer beams” built under the existing deck, at each end of each span. Afterwards the weight of the deck is transferred on the new beams and the new piles through a combination of jacking and grouted pot bearings. In addition, the deck will be reinforced using a combination of well-known techniques.
Strengthening of Two Major Highway Viaducts in Germany
Authors: Novák Balthasar , Reinhard Jochen , Pelke Eberhard , Boros Vazul , Roth Carolin
Published: February 2021

An entire generation of reinforced concrete highway bridges built in the post-war period in Germany is rapidly approaching the end of their lifespan. The federal government and regional highway departments have realized the necessity to replace these structures. Meanwhile measures need to be taken in order to extend the lifespan of the decaying bridges until such replacement becomes available. Two major highway viaducts in the federal state of Hessen provide examples for the temporary support of prestressed concrete bridges. These two realized structures show, how with smart customized measures critical bridges can be strengthened and an essential increase in lifespan can be achieved.
Rehabilitation of Flon Arch Bridge
Authors: Broquet Claude , Fargier Guillaume , Menétrey Philippe
Published: February 2021

The bridges over the Flon river were designed in 1964 by Sarrasin, a Swiss pioneer in reinforced concrete bridges. They are an illustrative example of the technique used to minimize the use of materials by, among other things, dividing the bridge deck in consecutive parts.

The mountain side bridge over the Flon river is in poor condition. The degradation of the half-joints is particularly concerning. This poses a risk for the structural integrity of the bridge. The aim of the rehabilitation project is to concrete every half-joint thus removing any risk associated with keeping them (brittle failure, fall of deck in case of seismic activity & progressive degradation). This solution will however modify the static system of the bridge.

The joints will be concreted using temporary steel structures placed under the deck, linking both sides of the joints. The joints are then demolished, thus removing all chloride contaminated concrete. The abutments are modified to allow horizontal movement. They are designed to include an access, with expansion joints and sliding bearings that are easily accessible for any maintenance work. The deck slab is reinforced by removing the cover concrete and adding a micro-concrete layer on the whole surface. The arches, piers and crossbeams are reinforced to maintain the integrity of the bridge. These reinforcements are made by wrapping the different concrete parts with carbon sheets or lamellas (FRC). The noise barriers laterally attached to the edge beam of the deck are replaced.

The construction project allows continuous traffic on the bridge during the works with only three work phases during which traffic lanes are modified.
Influence of the Design Review Process on the Structural Design Engineer due to Human Factors
Authors: Brehm Eric , Hertle Robert
Published: February 2021

It is common sense, that human error is the major cause for structural collapse [1]. Design review is the most effective way to rid human errors out of the design process and thus most societies have procedures for the design review installed. These systems work differently, e.g. preventive or repressive, and consequently affect the involved parties differently.

In this paper, the effect of different design review systems on the engineer as an individual will be assessed by addressing human factors that influence design decisions. The paper will focus on the structural design engineer, the effects on other included parties will be assessed in following studies.

The goal is to provide a better understanding of the impact of the design review procedure on the individual. Human factors affect the design engineer subconsciously and influence the decision- making in a significant way. Awareness of these factors and the corresponding influence due to the design review system will improve the design outcome and the relationship of design engineer and design review engineer.
Communication: Megaprojects' Biggest Risk that No-one is Talking about
Authors: Jurgens Christiaan J. , Matchett Richard N.
Published: February 2021

Megaprojects are known to have larger and more complex communication networks than regular construction projects. From literature however, three out of four common causes of megaproject failure may be linked to communication risks.

This investigation shows that certain communication process areas have a strong impact on Client Satisfaction and a moderate impact on a construction project's Quality, Time & Cost outcomes. Communication during the Project initiation phase is seen to be most important.

This study also identifies a possible communication deficit related to increasing team knowledge over time.

"Communication" is thus classified as the biggest risk that modern megaprojects face.
Seismic Probabilistic Risk Assessment of Weir Structures considering the Earthquake Hazard in the Korean Peninsula
Authors: Choi Byounghan , Alam Jahangir , Kim Dookie
Published: February 2021

Seismic safety evaluation of weir structure is significant considering the catastrophic economical consequence of operational disruption. In recent years, the seismic probabilistic risk assessment (SPRA) has been issued as a key area of research for the hydraulic system to mitigate and manage the risk. The aim of this paper is to assess the seismic probabilistic risk of weir structures employing the seismic hazard and the structural fragility in Korea. At the first stage, probabilistic seismic hazard analysis (PSHA) approach is performed to extract the hazard curve at the weir site using the seismic and geological data. Thereafter, the seismic fragility that defines the probability of structural collapse is evaluated by using the incremental dynamic analysis (IDA) method in accordance with the four different design limit states as failure identification criteria. Consequently, by combining the seismic hazard and fragility results, the seismic risk curves are developed that contain helpful information for risk management of hydraulic structures. The tensile stress of the mass concrete is found to be more vulnerable than other design criteria. The hazard deaggregation illustrates that moderate size and far source earthquakes are the most likely scenario for the site. In addition, the annual loss curves for two different hazard source models corresponding to design limit states are extracted
Seismic Assessment and Retrofit of the Caronte Viaduct (A55 Highway, Martigues)
Authors: Davi Denis
Published: February 2021

Because of advanced disorders, the Caronte emblematic viaduct of Martigues in the South of France (A55 Highway) was submitted to a repair and strengthening operation, which also included seismic assessment and retrofit. After having compared different possible seismic retrofitting strategies, the performed studies led to a solution consisting in replacing and softening the bearing system of the bridge, adding lateral shear keys at each abutment and pier and installing high capacity prestressed seismic dampers in the longitudinal direction at each abutment. Specific geotechnical tests were also carried out that enabled to avert soil liquefaction hazard on this very sensitive site. The proposed solution leads to justify a level of performance close to 70% of what is required for new bridges according to current French seismic rules, for an estimated cost of about 15% of the global repair cost and a repair to rebuild ratio barely higher than 1%.
Reproduction of Long-span Bridge Seismic Responses Involving Tower- girder Pounding and Tower Link Failure Estimation for Large Earthquakes
Authors: Takeda Tomoaki , Mizutani Tsukasa , Nagayama Tomonori , Fujino Yozo
Published: February 2021

During 2011 Great East Japan Earthquake, tower-girder transverse pounding was observed on Yokohama-Bay Bridge. Damage on the wind tongue due to pounding potentially leads to the damage of other members such as failure of the tower link. However, this pounding was not considered during design time and damage process after the damage of the wind tongue has not been clarified. In this study, a multi-scale model is constructed by combining the global frame model and the local FE model, which consists of shell and solid elements. Then, dynamic analysis of the multi-scale model is conducted to clarify the damage condition and the deformation of the wind tongue during large earthquakes. As a result, the base part of the wind tongue is yielded during the level 2 earthquakes and the tower link failure can occur due to large displacement after the damage of the wind tongue.
An Experimental Study on Seismic Performance of Concrete-Filled Steel Piers
Authors: Kanda Shinya , Matsubara Takuro , Tajima Hitoshi , Okui Yoshiaki , Shiji Kenichi , Okada Seiji
Published: February 2021

Cyclic loading experiments for SM570 steel piers filled with concrete were carried out to obtain basic data on the seismic performance. On the basis of the survey results of the existing steel bridge piers of the Tokyo Metropolitan expressway in Japan, model parameters, such as axial- force ratio and slenderness ratio were selected in consideration of effect on seismic performance, especially ductility after yielding. Furthermore, a design method for retrofitting existing SM570 steel piers designed according to an old design code was investigated based on the deformation performance obtained in the experiment.
Investigation on Phase Lag of Bidirectional Model in Nonlinear Seismic Analysis
Authors: Liu Yanyan , Igarashi Akira
Published: February 2021

The phase lag angle between the displacement and nonlinear restoring force vectors found in steel bridge piers under circular displacement loadings is one of the quantitative measures of multi- component interaction of bidirectional nonlinear restoring force. In this study, influence of the phase lag angle on dynamic response of structures under bidirectional seismic excitation is investigated using a modified rigid-plastic bidirectional restoring force model. The results of nonlinear time history analyses of the bidirectional rigid-plastic model with a uniform resultant force-displacement relationship and varying phase lag angles under bidirectional accelerograms show that the bidirectional model with a higher phase lag angle induces a higher circumferential energy dissipation, resulting smaller radial displacements.
Contributions of Higher Modes of Tall Piers under Seismic Excitation
Authors: Chen Xu , Li Jian-zhong
Published: February 2021

Many bridges in the mountainous areas of southwest China are built with tall piers characterized by large structural flexibility and significant distributed mass. Seismic performance of these bridges is significantly influenced by higher-mode effects of the tall piers. However, no parameter has been presented to evaluate the effects of higher modes of tall piers to date. Considering both the mass participation factor and characteristics of ground motions, the base shear-force factor was proposed in this paper, estimating the contribution of the first n modes of tall piers to the shear force at the pier base. The results showed that when subjected to ground motions with different characters, the base shear-force factor can present the influence of higher-order modes to the seismic demand of tall piers more effectively than the mass participation factor. Further, the shear force demand is more sensitive to the higher-mode effects, compared with bending moment.
Numerical Seismic Assessment of Masonry Made of Compressed Earth Blocks
Authors: Nitiffi Riccardo , Imbimbo Maura , Grande Ernesto , Oliveira Daniel V.
Published: February 2021

Masonry construction built with compressed earth blocks (CEBs) is one of the most significant examples of sustainable buildings based on the earth construction technology. Nevertheless, despite the economic and environmental advantages, the seismic vulnerability of these construction is object of concern. The aim of the present paper is to numerically investigate the response of a one-story CEB masonry building subjected to horizontal forces simulating seismic actions. Both modal and non-linear static analyses are performed through the commercial Finite Element (FE) code TNO-DIANA by using a 3D FE macro-modelling approach. During the analyses, particular attention has been devoted to the influence of some structural elements such as interior partition walls and ring beams.
Investigation of Bearings Unseating of Cable-stayed Bridges under Earthquakes
Authors: Li Yong-xing , Xu Wen-jing , Yi Jiang , Li Jian-zhong
Published: February 2021

Under strong earthquakes, bearings of cable-stayed bridges usually separate from the main beam. This paper adopts a cable-stayed bridge as the background project to study the influences of bearings unseating. Moreover, the effects of auxiliary piers on bearings unseating of cable-stayed bridges subject to earthquakes are also researched. Numerical results show that bearings unseating that may happen on transition pier and main tower result in large vertical displacement of main beam and bearings pressure. The position of auxiliary pier on the side span has an important influence on the bearings compressive force and girder vertical displacement of transition pier. Increase of bearings constant load pressure of auxiliary piers can reduce the vertical displacement of girder to some extent. However, the large bearings constant load pressure may causes large pounding force that should not be neglected in cable-stayed bridges design.
Modelling of Structural Damping in Time History Analyses of Seismic Response of Chacao Bridge
Authors: Kaasa Lars Halvor , Nessa Kristin , Rønvik Jarle , Jakobsen Svein Erik , Cheikh Mhamed Aymen
Published: February 2021

This paper describes how structural damping has been applied in Time History Analyses (THA) of seismic response of Chacao Bridge in Chile, which is located in an active seismic zone. Correct modelling of structural damping becomes particularly important because of the concrete pylons, which will have high energy dissipation (i.e. structural damping) during a severe earthquake. Tuning global Rayleigh damping parameters are usually trivial for simple structures with only a few governing modes, but becomes difficult for a soft suspension bridge with stiff, but still flexible, pylons on relatively soft piles. The solution has been to apply element-wise Rayleigh damping, where the damping parameters of each element is tuned to fit important modes for the structural part the element is a part of. The procedure is tested by comparing acceleration-based THA to RSA.
Influence of Phase Polarity of Bidirectional Seismic Ground Motion on Dynamic Response of Asymmetric Bridges
Authors: Igarashi Akira , Gigyu Subaru
Published: February 2021

For seismic performance assessment of bridges to determine the maximum structural response under various bidirectional ground motions, the influence of the phase polarity, which is defined as the distinction of the sign of one of the two ground motion components of the bi-directional input, on the maximum structural response is investigated by theoretical formulation and numerical verification. Using simplified numerical model of curved bridges with seismic isolation and energy dissipation devices, it is numerically shown that the maximum seismic response of the structure can be greatly affected by the choice of the phase polarity of the input ground motion, and the influence becomes more significant if the dynamic asymmetry is more severe in the curved bridges that can be enhanced by the choice of the orientation angle of energy dissipation devices.
Long Term Monitoring of Millau Viaduct
Authors: Clément Antoine , Lançon Hervé , Cachot Emmanuel , Servant Claude
Published: February 2021

Millau Viaduct is a multi-span bridge located in the south of France which holds several world records : including longest cable stayed-bridge (2460 m) and tallest pier (245m). For megastructure like Millau Viaduct, performance monitoring is mandatory to guarantee the safety of users and optimize maintenance costs. Practically speaking, this is achieved through the continuous monitoring and the estimation of damage sensitive features extracted from static and dynamic measurements. This paper focuses on data analysis strategies carried out to extract these damage sensitive features. Regarding static measurements, operational and environmental effects are removed using iterative multilinear-regressions to reveal long term variations. The proposed approach is able to detect very light changes in piers tilt or in expansion joint movement. When dealing with dynamic measurements, natural frequencies are automatically identified through the method of frequency domain decomposition. The goal is to quantify their sensitivity to structural changes over a monitoring period of ten years. The study shows that once temperature effect is removed using regression methods, decrease of transversal frequencies is revealed which might be compatible with piers creeping.
Prediction of Breakage Position and Remaining Fatigue Life of Corroded Bridge Wires using 3D Scanner
Authors: Miyachi Kazuhiro , Nakamura Shunichi
Published: February 2021

Cables and stays of suspension bridges and cable-stayed bridges have been heavily corroded and broken all over the world. Although cable corrosion can be found by visual observation, it is difficult to find the dimension and distribution of corrosion pits. Therefore, there is no established method to predict fatigue failure, the breakage position and remaining fatigue life of the existing wires. In this study, the risk assessment system of corroded bridge wires using a 3D scanner was established. The surface roughness of corroded wire was measured by 3D scanner and the dimension and corroded area of corrosion pits were obtained. It was found that the most corroded part corresponded with the actual broken position, which makes possible to predict the breakage position. In addition, by comparing the fatigue strength with the S-N curves, the remaining life of corroded wires can be predicted considering the dimension of corrosion pits.
Forces in Temporary Piers in Bridge Built using Balanced Cantilever Method
Authors: Jarosz Jakub Jan
Published: February 2021

The paper concerns the construction of an extradosed bridge in Poland. The bridge has been designed as a four span structure and was erected using balanced cantilever method. The length of the main span is 206 m and it holds the record for extradosed bridges in Europe. In order to improve safety of the building during construction, each of the cantilevers was stabilized by a temporary pier. The values of normal forces in temporary piers were controlled by sensor gauges installed on temporary steel bearings. Based on the measured deformations, real-time charts of normal forces in the temporary piers were recorded. Normal forces in temporary piers changed when the arms of cantilevers were loaded asymmetrically. The increase in normal forces resulted from the movement of form travellers and segment casting. In this way theoretical changes of normal forces values in temporary piers could be compared with the real ones.
Better Understanding of Tide’s Influence on Half-cell Potential Measurements for Reinforced Concrete in Marine Environment
Authors: Bourreau Lucas , Bouteiller Véronique , Schoefs Franck , Gaillet Laurent , Thauvin Benoît , Schneider Julien
Published: February 2021

Main damage occurring on reinforced concrete (RC) structures can be attributed to the corrosion of the rebar. Chloride ions penetration and/or carbonation, as major causes of RC corrosion, are well understood for onshore structures. When dealing with structures in marine environment, more parameters must be considered, as the different exposure zones (tidal, splash and atmospheric) will have a significant influence on the corrosion behavior.

This article deals with the corrosion diagnosis of the piers of the ile de Ré bridge. The objective is to provide an effective method to identify the different exposure zones based on the non-destructive measurements (half-cell potential) that are modelled taking into account the influence of the tide.
Measurements and simulation of temperature in a portal frame bridge
Authors: Gottsäter Erik , Larsson Ivanov Oskar , Molnár Miklós , Plos Mario
Published: February 2021

Since thermal loads can cause cracking, they are important to consider in bridge design. In order to evaluate and develop thermal load cases based on real simulations, models for simulating temperatures can be used. In this paper, a model for thermal simulation is used to simulate temperature in a portal frame bridge outside Lund, Sweden. The results are compared with temperature measurements in 13 locations in the same bridge, which were made during a 12- month period. The results show that although many important material parameters were unknown, the model could recreate both daily and seasonal temperature variations, although it tended to render temperatures about 1°C lower than the measurements, at least during summer. The model can be used in future work in determining thermal load values for the specific bridge type, assuming the model uncertainty is considered by e.g. adding 1°C to calculated load values.
Monitoring Cracks on Concrete Surfaces using Multi-temporal Images
Authors: Santos Bruno O. , Valença Jónatas , Júlio Eduardo
Published: February 2021

For concrete structures, the characterization of cracks, namely initiation, opening, and propagation, as well as of cracking pattern, plays an extremely important role in the scope of structural health monitoring. The authors have already developed a method, MCrack, based on computer vision and image processing with this goal. However, this is focused on a given concrete surface at a given instant and, thus, monitoring cracks through time, namely between periodic inspections, requires permanent and static camera stations. While this is most adequate for laboratorial tests, for on-site application it implies the need of work-intensive procedures (that are not error proof) to ensure the overlap of images acquired at different time instants.

Recent research developments in image registration have a significant potential to be implemented in MCrack, allowing to monitor cracks with simple and light methods, more prone for on-site monitoring. In this paper, a first approach of MCrack-Propagation method is presented, as an evolution of MCrack, based on matching image features. The main improvement is the automatic feature matching between pairs of multi-temporal images of the same surface region. This enables to automatically track the evolution of cracks width on concrete surfaces.

The MCrack-Propagation method improved the reliability of crack width measurement due to the higher number of measuring points than in previously presented methods. It is also light and easy to implement avoiding work intensive procedures, as those using image segmentation methods or traditional methods that require experts to contact with the cracks.
Knowledge Model for Forensics in Civil Engineering
Authors: Breysse Denys , Taillandier Franck , Baudrit Cédric
Published: February 2021

Failure analysis in civil engineering mostly remains a field for experts. Since experts can derive valuable information from any failure case, a key challenge is that of producing new knowledge from a set of cases. Another challenge is to draw similarities between different failure cases, in order to draw general lessons. We develop in this paper an original modelling approach, based on the conceptual graph formalism, aiming at addressing these two issues. The approach is explicited and the developed tool is applied to an existing bridge failure, in order to highlight how it could enable the production of new knowledge.
Seismic Retrofit of Industrial Building using Damping Devices
Authors: Sonda Devis , Cossu Marco , Pollini Andrea
Published: February 2021

The prefabricated industrial buildings, similar to the one presented in this paper, featured a high seismic vulnerability during the 2012 Emilia Earthquake (Italy). The main structural deficiencies were a consequence of the lack of connection between columns, beams and roof elements. The case study presented in this paper is an industrial building composed of two structural units with different initial stiffness. The strengthening approach was different for the two parts. The stiffer part was equipped with Buckling Restrained Braced Frames (BRBF), thus adding stiffness and energy dissipation. The more flexible part was decoupled from the rest of the building and fluid viscous dampers were installed in the joint between the two structural units. The relative movement between the two parts can activate the damping devices, which dissipate part of the input seismic energy, hence a structural weakness is turned into a positive resource for energy dissipation.
Seismic Performance of Precast Segmental Bridge Piers with High- strength Bars based on Cyclic Loading Test and Numerical Simulation
Authors: Tong Teng , Zhuo Weiding , Liu Zhao
Published: February 2021

Compared to cast-in-place (CIP) piers, precast segmental bridge piers benefit the accelerated construction, and easy-to-repair after an earthquake. Nevertheless, precast segmental piers also suffer from lower energy dissipation capacity. High-strength bars (>500 MPa) incorporated with precast piers, as energy dissipation bars, have great potential to improve their seismic performance. This paper presents the cyclic loading tests of the ductile, flexural-dominated precast piers with both high-strength (HRB600) and conventional (HRB400) bars. The experiment witnessed the minor damage in the plastic hinge zone and small residual displacement. With respect to conventional bars, high-strength bars apparently enhanced not only load capacity but energy dissipation. The skeleton curve of cyclic loading test can be precisely predicted by the analytical pushover method, which is based on the plane assumption and considers the effect of bond length between high- strength bars and the grouting mortar. A new finite element model based on the fiber-cross section implemented in Opensees, is proposed and capable of accurately simulating the hysteretic behavior of these precast piers.
Simple Strengthening Techniques for Non-engineered Buildings against Seismic Actions
Authors: Traykova Marina , Giarlelis Christos , Lampropoulos Andreas , Dritsos Stephanos , Moseley Jon
Published: February 2021

It is estimated that non-engineered construction accounts for more than half of the buildings in most of the cities of the developing world. These buildings account for most of the collapses and fatalities during earthquakes. To address this problem, the possible solutions are either to limit their construction in highly seismic zones or strengthen the existing ones. Lack of integrity of a building’s structural elements, improper detailing of a building’s structural elements and low quality of construction materials are typical problems found in many of these structures due to misconceptions, lack of guidelines and skilled technicians. In this work, some of the most popular strengthening techniques for non-engineered buildings based on different case studies from various countries are presented. General conclusions and recommendations, which may serve as guidelines for future rehabilitation works, are drawn.
Fibre Reinforced Geopolymer versus Conventional Reinforced Concrete layers for the structural strengthening of RC beams
Authors: Al-Majidi Mohammed Haloob , Lampropoulos Andreas , Cundy Andrew , Tsioulou Ourania , Alrekabi Salam
Published: February 2021

A common technique used to increase the flexural capacity of RC beams is the external application of RC layers. In this case, crucial parameter for the efficiency of the examined technique is the connection between the new layer and the existing concrete, since lack of sufficient connection at the interface may lead to premature failure of the strengthened elements. Another crucial parameter for the durability of the strengthened elements is the corrosion of the reinforcement of the layers. In the current study, fibre reinforced geopolymer concrete layers reinforced with steel bars were used for the flexural strengthening of reinforced concrete beams. Accelerated corrosion tests were conducted followed by flexural loading. The results indicate that, the addition of fibre reinforced geopolymer concrete offers improved load performance and durability, since higher maximum load increment was observed and the effect of corrosion was found to be negligible.
Structural upgrade of deficient Unreinforced Masonry structures using Ultra High Performance Fibre Reinforced Concrete
Authors: Lampropoulos Andreas , Tasji Ahmad , Tsioulou Ourania
Published: February 2021

The structural upgrade of substandard Unreinforced Masonry (URM) is an urgent need worldwide and especially in earthquake prone areas and in low and middle income countries. The majority of the existing URM buildings in these areas have not been designed to resist seismic action, and in many cases, substandard materials have been used, therefore the structural strengthening of these structures is essential. The strengthening of existing low strength masonry is a quite challenging task since the effectiveness of the external application of high strength materials (e.g. Fibre Reinforced Polymers) is limited due to the poor connection between the new materials and the existing substrate which leads to de-bonding and premature failure of the strengthened structures. In this study, a novel strengthening technique has been examined using Ultra High Performance Fibre Reinforcement Concrete (UHPFRC) layers in addition to partial replacement of the existing mortar with UHPFRC. Experimental investigation has been conducted on brick walls constructed using low strength bricks. UHPFFRC layers with various thicknesses with and without UHPFRC at the joints have been applied to the URM walls and flexural out-of-plane tests have been conducted. The experimental results demonstrate that the proposed technique can considerably improve the ultimate load and the ductility of the URM walls. Also, the proposed technique offers improved UHPFRC-to-URM interface conditions.
Value of Information in the Maintenance of a Tendon supported Large Span Roof
Authors: Maslak Mariusz , Pazdanowski Michał , Howiacki Tomasz
Published: February 2021

Possible monitoring strategies for snow covered roofs of tendon based bearing structures and spanned over large area halls are considered and compared in this paper. Service reliability of such roofs is usually determined by the risk of estimated tensile stresses exceeding the bearing capacity of single tendons. The balance of obtained gains versus incurred costs quantified via the so called value of information factor has been assumed as the eficiency measure of the considered solutions. This factor takes into account, for each considered case, both the failure probability and the consequences of such failure. The considered strategies are differentiated by the complexity of actions taken as well as the uncertainty level of the formal model applied to develop the mathematical description of the problem.
Failure Probability for Extreme Load Cases evaluated by FE- calculations – A Case Study for the Rockfall Protection Gallery Rieinertobel
Authors: Kurihashi Yusuke , Komuro Masato , Schubert Matthias , Custer Rocco , Schellenberg Kristian
Published: February 2021

The safety level evaluation of an existing reinforced concrete rockfall protection gallery for a specific load case is investigated by estimating the failure probability based on the results of dynamic impact response analyses. The three-dimensional elasto-plastic finite element model contains four main parameters with large influence on the impact resistance. Ten FE-simulations with different combinations for the gallery parameters are carried out. A failure criteria is defined by the elastic recovery ratio and used as damage index of the roof slab. A regression function between the elastic recovery and model parameters is obtained from the FE-results and used to establish a surrogate model of the elastic recovery ratio. From it, the probability of failure is assessed by a Monte Carlo simulation. This methodology to predict the failure probability of a structure for a given extreme load case considering the model uncertainties can be applied independently from the model and can be used to compare the safety level with the requirements from the structural codes.
Rating of Prognostic Performance Indicators through the Indicator Readiness Level
Authors: Limongelli Maria Pina , Orcesi Andre , Vidovic Anja
Published: February 2021

To move from corrective maintenance to preventive maintenance, it is essential to be able to monitor the bridge component behaviour and detect any drop in the performance level before major failure occurs. Performance Indicators are used to deal with life-cycle deterioration of infrastructures and characterize the current and future structural conditions. In the context of Cost Action TU1406, several performance indicators have been identified to serve as benchmarks in the establishment of a Quality Control plan. These Indicators can be qualitative or quantitative based, data-driven or obtained with physically-based models. They can be collected during principal inspections, through a visual examination, a non-destructive test or a temporary or permanent monitoring system. Moreover, they can describe the current condition (diagnostic performance indicators) and/or forecast future conditions (prognostic performance indicators). Several Performance Indicators are currently the object of research effort and not yet ready at for a systematic application to Quality Checks. The Indicator Readiness Level scale has been previously proposed by the authors to rate the maturity levels of Performance Indicators. This scale is herein applied to prognostic performance indicators used to characterize the performance of a bridge in terms of its ability to perform the structural function.
An Overview of the European Situation on Quality Control of Existing Bridges – COST Action TU1406
Authors: Matos José C. , Casas Joan R.
Published: February 2021

Across Europe, the need to manage roadway bridges efficiently led to the development of multiple management systems. Although presenting similar architectural frameworks, the condition assessment procedure can be identified as one of the difference that distinguishes them. This dissimilarity constitutes a divergent mechanism that has direct interference in the decision making process leading to considerable variations 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. Such purpose requires the establishment of recommendations for the quantification of performance indicators, the definition of performance goals and a guideline for the standardization of quality control plans for bridges. The purpose of Work Group 1 (WG1) was the characterisation and definition of performance indicators. WG2 assessed a methodology to link performance indicators to performance goals. WG3, based on the results of WG1 and WG2, will provide a methodology to establish quality control plans for diﬀerent types of bridges. By developing new approaches to quantify and assess bridge performance, as well as quality specifications to assure expected performance levels, bridge management strategies will be significantly improved, enhancing asset management of ageing structures in Europe. The work developed by COST Action TU1406 will be presented.