bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the impact of dynamic orthosis “Dunag 02” on muscles of the lower limbs during gait in children with hypotonia and ataxia
Authors: Małachowska-Sobieska Monika , Demczuk-Włodarczyk Ewa , Wronecki Krzysztof , Skolimowski Tadeusz , Kwiatkowski Robert , Skolimowska Beata , Staniszewski Łukasz
Published: July 2016

In addition to the standard methods used to form the correct postural and locomotional patterns in children with neurological deficits, there are many methods to support the improvement. One of them is use of the dynamic orthosis “Dunag 02”. The aim of the study was to evaluate the impact of the dynamic orthotic “Dunag 02” on muscles of lower limbs in children with hypotonia and ataxic gait. The study involved two girls: 5-year-old with hypotonia and ataxia and a 15-year-old with a cerebellar syndrome. Evaluation of performance of the dynamic orthosis “Dunag 02” was based on “global” electromyography (EMG). In case of the 5-year-old girl with hypotonia and ataxia, use of the dynamic orthosis “Dunag 02” had a moderate effect on ataxia and allowed for greater postural stability, and in 15-year-old girl with cerebellar syndrome, activity and functions were improved.
Newest concepts of physiotherapy research
Authors: Wysoczańska Emilia , Skrzek Anna
Published: July 2016

The subject of the paper is the variety of newest research concepts in the field of physical therapy. The research, which is being conducted worldwide, deals with different issues. Researchers speculate that using stem cells may have considerable significance in treating patients with spinal cord injuries. Another subject of great interest includes studies on spinal cord neuroprosthetics and epidural stimulation. The results show the importance of the newest findings. Moreover, researchers are analysing e.g. the use of cannabinoids in multiple sclerosis treatment or the role of yoga in treating back pain. The results show the diversity of physiotherapy as a field of study.
Optimization of the care model for elderly in Poland
Authors: Lwow Felicja , Korzeniowska Małgorzata , Dadacz Joanna , Hladik Ewa , Łukojko Agata , Denkowska Anna
Published: July 2016

The demographic situation of Poland as well as other developed countries shows a growing number of people at retirement age. According to the data from GUS (Central Statistical Office), their number reached 6.5 mln in Poland in 2011, and the prognosis for shows 8,3 mln by the year 2035. The consequence of this fact is a necessity of including the specificity of this age group in the functioning of Polish health care as well as in preventive medicine and health promotion. Unifying the health needs of this age group would be disadvantageous due to the diversification of physical efficiency level in the psychosomatic and social aspect. Nevertheless, the key problem is to distinguish the optimal health care models which include not only chronic conditions and dysfunctions but also the quality of life and socially independent life style that guarantee the lack of isolation and social exclusion. Distinguishing the four action models, namely people considered as healthy by the system, autonomously functioning people with chronic conditions, and people who need other people or institutional care to function in a society, seems to cover the individual needs of this group. Concluding, the National Health Care needs to work out some proceeding algorithms for these models. The optimal program adjustment for the needs of the target group would most certainly improve the effectiveness of the Health Care.
Level of physical activity in intellectually disabled adults
Authors: Celebańska Diana , Gawlik Krystyna
Published: July 2016

Introduction: Physical activity is one of the basic components of lifestyle. However, due to the technological developments the level of physical activity in modern society is decreasing. Such a phenomenon is also present among people with intellectual disability, who lead even more sedentary lifestyles. Physical activity and well-balanced diet play a key role in a healthy lifestyle and prevention of civilization diseases.

Aim of the study: To assess the level of physical activity among adult people with intellectual disability.

Materials and methods: The study group consisted of 69 adults with varying levels of intellectual disability, 27 females and 42 males, aged 21 to 54 years. The participants monitored their number of steps for 7 consecutive days with a pedometer. The results were analyzed according to gender, age, the level of intellectual disability, and BMI.

Results: Adults with intellectual disability seem to be insufficiently active. Only 16% of participants exceeded the recommended amount of 10,000 steps, and the average for the whole group was 6,656 steps per day. No significant correlation was found between the level of physical activity and the level of intellectual disability, gender, age, or BMI.
Toward the Next Generation of Concrete Structures: Recent Advances in UHPC Technology
Authors: Kim Byungsuk , Koh Gyungtaek , Cho Jeongrae , Park Jongbum , Kim Youngjin , Park Sungyong , Cho Keunhee , Joh Changbin , Kang Jaeyoon , Kwon Kihyon
Published: July 2016

This paper examines the history of UHPC, as the latest technology for concrete structures, from the
development of the material and the corresponding specifications to its application on field. The
advantages and disadvantages of UHPC are analysed and future research directions are derived.
Sustainable Construction in Concrete Structures – What to Think to the Future
Authors: Supartono F. X.
Published: July 2016

This paper presents various aspects of the sustainable infrastructure development that is mandatory
for civil engineers to promote or even be a leader in pioneering its implementation, particularly in
concrete production and construction that is the topic of this paper. It can be a wide range of
application from design, materials, construction method, cost effectiveness and durability, for which
the engineers should be able to use their knowledge and abilities to manage their activity in
harmony with the environment, as well as to inspire the optimism to create a sustainable
infrastructure world. At the end of this paper, engineers are encouraged to learn from the past and
think to the future, as well as to always update and improve the voluntary action plans on
sustainable development, which will lead humanity and environment to coexist harmoniously.
Scaled Model Test of RC Column Considering Strain Distortion of Model Concrete
Authors: Park Jamin , Cho Jae-Yeol
Published: July 2016

It is required to estimate the exact dynamic response of RC column to prevent the seismic failure. By the limitation from the capacity of test facility and the cost for a specimen production, the vibration test using real-scale structures is typically not possible. Therefore, the test using scaled model can become an economic alternative. To design the small-scale model of RC structures, it is necessary to use micro-concrete whose aggregate size is smaller than normal concrete. Therefore the material characteristic of concrete for both prototype and scaled model becomes much different. But the material characteristic of reinforcement for both prototype and scaled model is typically not much different. From this discrepancy, a strain distortion is occurred. In this study a new similitude law to minimize the error from the strain distortion and the method for estimating strain ratio of scaled model is developed. Numerical verification for the dynamic analysis of RC column with rectangular section was conducted. Analysis results show that response of the scaled RC model using the suggested similitude law can predict the response of prototype structures with reasonable accuracy.
Behaviour of Partially Encased Composite Girder with Corrugated Steel Web under Combined Shear and Flexural Loads
Authors: He Jun , Lv Zhan , Li Chuanxi , Liu Yuqing
Published: July 2016

Concrete-encased composite girder with corrugated steel web is proposed to improve the
mechanical performance of continuous girder under hogging moment, avoiding the buckling of the
corrugated web and compressive flange caused by large combined shear force and bending moment.
The structural behavior under combined shear force and bending moment was investigated
experimentally and analytically, the load-carrying capacity and failure mode of composite girders
with different length of concrete encasement were investigated. Analytical results show that the
failure modes of composite girders depend on the length of concrete encasement, and the ratio of
shear to bending affects the shear stiffness after concrete cracking and ductility at ultimate load
state. Based on experimental results, the analytical evolution of shear strength and bending strength
were investigated, also interaction equation with respect to shear and bending strength was
proposed to evaluate loading capacity of such composite girders.
The Calculating Method of Dynamic Analysis of Beams with Variable Cross- Section Based on the Transfer Matrix Method
Authors: Wang Yuan , Shen Ruili , Wang Tao
Published: July 2016

Ruili SHEN Professor Southwest Jiaotong
University, Chengdu, China

rlshen@163.com

Ruili Shen, born 1963, received his doctor’s degree from Southwest Jiaotong University, China. His main area of research is related to modern bridge design theory and bridge structural dynamics.
Tao WANG
Ph.D., Lecturer Southwest University of Science and Technology, Mianyang, China 7015294@qq.com

Tao Wang, born 1983, received his civil doctor’s degree from Southwest Jiaotong University, China. His main area of research is related to bridge structural dynamics.

In order to solve dynamic analysis of beams with variable cross-section more efficiently, taking a class of widely used beams as the breakthrough point, the calculation method was established based on the transfer matrix method. Firstly, taking a single-span beam as the basic element, the element transfer matrix of continuous beams with variable cross-section was derived by solving the partial differential equation of motion. Secondly, the boundary and continuity conditions at the supports were utilized to reduce the overall transfer matrix. Thirdly, the general algorithm for solving dynamic characteristics of continuous beams with variable cross-section was established to obtain the natural frequencies and the mode shapes. Finally, by employing New mark Beta Methods, dynamic analysis under moving loads was realized. And then, taking MATLAB as the platform, a numerical calculation program was developed to solve dynamic characteristics and dynamic analysis of beams with variable cross-section. The results show that, compared with the finite element method, the proposed method was verified to be accurate, simple, and efficient.
Modelling Techniques for Buffeting Analysis of Long-span Bridges
Authors: Kavrakov Igor , Morgenthal Guido
Published: July 2016

Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. By well accepted classification, the aerodynamic forces are categorized into static, self-excited and buffeting forces for which different formulations apply based on the quasi-steady and the linear unsteady air-foil theory. This paper aims to investigate different formulations of the self-excited and buffeting forces in time domain by comparing the dynamic response of a cable-stayed bridge during the critical erection condition. The models are viewed from a complexity perspective, comparing the assumptions implied such as aerodynamic damping, admittance, fluid memory, aerodynamic nonlinearity and aerodynamic coupling. These are quantified based for design wind speeds which are typical for the construction stage.
Seismic Fragility Analysis of Bridge by Combining the Uniform Design Method and Response Surface Method
Authors: Li Huihui , Wang Yudong , Li Lifeng , Hu Sicong , Wu Wenpeng , Xu Shuo
Published: July 2016

In view of the large calculation research situation of the seismic fragility of bridges, the paper takes a continuous girder bridge as case-study, accounts for the uncertainties derived from the structural and earthquake ground motion. Combined with the uniform design (UD) and response surface methodology (RSM),an alternative seismic fragility analysis method is proposed. In order to verify the validity and applicability of the proposed method, what through comparisons in sampling frequency and computing time, response surface model accuracy and seismic fragility curves between the proposed method, Monte Carlo (MC), orthogonal design (OD) and central composite design (CCD) of response surface methodology. The case-study shows that the proposed method can be well applied to seismic fragility analysis efficiently and effectively. The results of fragility analysis of the proposed method are very close to Monte Carlo of response surface methodology. In terms of the sampling frequency and computing time, compared with Monte Carlo (MC), orthogonal design (OD) and central composite design (CCD) of response surface methodology, the proposed method is reduced by 99.70%, 58.49% and 8.70% respectively. And as for the structures response surface fit coefficients, compared with orthogonal design (OD) and central composite design (CCD) of response surface methodology, the proposed method are increased by 8% to 12% and 3% to 5% separately. Therefore, the proposed method has good application value in seismic fragility analysis.
Seismic Performance of Cable-Stayed Bridges Subjected to Different Types of Ground Motions
Authors: Wu Wenpeng , Hu Sicong , Li Lifeng , Li Huihui , Xu Shuo , Wang Yudong
Published: July 2016

Seismic response of the cable-stayed (CS) bridge under the earthquake are not consistent with the regular bridges for their different dynamic characteristics, in particular, when the CS bridges are subjected to the near-fault ground motions with velocity pulse. However, most of current literatures tended to study the seismic behavior of the CS bridges by using the deterministic analysis approach, and these literatures are not compared the variability of seismic response for the bridge subjected to different ground motions. Seismic fragility function is readily appropriate as a probabilistic analysis tool to quantify the performance of bridge due to its advantage to account for the uncertainty associated with ground motions. A representative medium-span concrete cable-stayed bridge is taken as an example, this study will firstly compare the seismic response of the bridge subjected to both near-fault and far-fault ground motions with identical peak ground accelerations (PGA), in order to highlight the obvious distinction. Moreover, two earthquake bins (far-fault bin and near- fault bin) are assembled to account for the uncertainty derived from ground motions. Because the common used PGA was proved to be inapplicable for fragility analysis of the long-period structures. Therefore, four common used intensity measures, e.g. PGA, PGV, PGD and SA, are selected to identify their priority for the fragility analysis of the CS bridge. Finally, the seismic fragility curves of some important components with respect to the optimal intensity measures are developed for the case-study bridges subject to two different ground motion bins.
Cold Reinforcement Method for Distortion-induced Fatigue Cracks of Steel Bridge
Authors: Wang Chunsheng , Zhang Yuxiao , Wei Xiaoqiang , Wang Yuzhu
Published: July 2016

Fatigue cracks seriously affect the safety and service life of steel bridges, and approximately 90% of which are caused by distortion-induced stress. It is urgent to search for an effective reinforcement or strengthening method for distortion-induced fatigue cracks in steel bridges. For this purpose, cold reinforcement methods are developed to reinforce the distortion-induced fatigue cracks in steel bridges, includingdrilling stop holes,bolting angle steel, bonding angle steel and hybrid reinforcement methods. Fatigue tests are conducted on full-scale steel girder models to study the distortion-induced fatigue mechanism and the effectiveness of cold reinforcement methods. Most of distortion-induced fatigue cracks initiate from the web gaps after certain loading cycles, and cold reinforcement methods are carried out when the cracks propagate to a certain length. Test results show that drilling stop hole cannot prevent fatigue crack propagation, but with the other three methods, out-of-plane distortion and stress level decrease sharply, and fatigue cracks further propagation is not observed. Based on experimental study, hybrid reinforcement method issuggested for distortion-induced fatigue cracks reinforcement due to the significant effectiveness and convenient construction.
Electrochemical Test Research on Corrosion Resistance of Cable Wires with Different Protection Layers
Authors: Xie Faxiang , Liu Fa , Hu Xingyu
Published: July 2016

The stay cables are usually subjected to continuous erosion from the environment in their service period. The protective layer on the cable wire is an important barrier for the cable corrosion resistance. Therefore, the durability of the cable depends greatly on the proper selection of the protective layer, which makes a big difference comparing with the bare cable wires. This paper studies on the corrosion performance of 6 common kinds of cable steels under the same corrosion environment with electrochemical test methods. The corrosion rates of different kinds of steel bars under various covers are tested and obtained. The results can provide more accurate reference for the designers of cable stayed bridges to selecting a proper kind of cable wires during the bridge construction or maintainers to estimate the durability of the stayed cables.
Influence of Massive Substructures on Capacity Design Method
Authors: Mao Yudong , Li Jianzhong
Published: July 2016

When adopting “capacity protected design method”, inertia force of piers is neglected and inertia force of pile cap is calculated by static method in the current code, which may be appropriate in terms of short and medium span bridges as the mass of pier and pile cap in those bridges is negligible and can be ignored. However, with respect to long-span continuous bridges, the bridge columnsand pile caps are large dimensional and massive,and definitely causes considerable seismic forces, which cannot simply be neglected. This paper mainly deals with the analysis of the seismic behavior of bridges characterized by massive piers and pile caps, focusing on the validity of current “capacity protected design method”. It has been shown that this design strategy may prove inadequate in long-span continuous girder beams whose seismic behavior is governed by pier or pile cap dynamics and, specifically, in case of massive piers and pile caps. Take a typical long-span continuous bridge(with massive piers and pile caps) as the project background, a series of nonlinear dynamic time-history analyses were carried out in order to assess the influence of the piers and pile caps. Compared with the results of nonlinear time-history method, the shear and moment values calculating from code-specified capacity protected design method underestimate the inertia force contribution of piers and pile caps. Therefore,as for ductile and seismic isolation design strategy, there is a need to adjust existing design guidelines to better capture the seismic response of long-span continuous bridges.
The Rebuilding of the Harchies Bridge
Authors: Dister Vincent , Ney Laurent
Published: July 2016

The new Harchies Bridge, spanning 68 m, replaces a prestressed concrete bridge built in the 1950’s during the construction of the Nimy-Blaton Canal near Mons, Belgium.

The new structure is an integral abutment bowstring bridge spanning 68 m over the canal. It is supported on two cantilevered concrete abutments that are structurally continuous with the bridge superstructure. Each end of the steel arch is connected to the concrete abutment using very high- strength anchor bars.

The edges of the 13.4 m wide deck are covered with a steel plate. This plate, continuous over the entire length of the bridge, acts, with the slab, to carry the tensile forces which counteract the arch thrust. The plate also supports the structure of the stainless steel net railing. The deck consists of a variable height concrete slab supported every 5 m by transverse steel members. These members, formed with variable height welded steel box sections, work compositely with the concrete slab and transfer the loads from the deck to the hangers. The hangers are plain steel bars, galvanized and painted. They are connected to the deck edge plate at the bottom and to the interior web of the arch at the top.

As the structure is an integral abutment bridge expansion joints are not needed between the deck and the abutments. This typology improves the overall performance of the structure and, more specifically, increases its durability. However, the structural design of the bridge needs to take into account the soil-structure interactions resulting from horizontal displacements related to shrinkage, creep and thermal effects.

Since the chosen structural typology was the first of its kind in Wallonia, the structure was instrumented to monitor its behavior over time: stress gauges have been installed in the hangers and the arches, along with temperature sensors for ambient air and steel, and inclinometers and pressure sensors at the abutments.
Permanent Damages of Structural Components in Existing High-Rise Steel Buildings Subjected to Rare Earthquakes
Authors: Bai Yongtao
Published: July 2016

Severe ground motions generate permanent damages and residual deformations on various existing high-rise steel buildings, due to the effects of local-failure in steel and CFT members on the seismic damages have not been accounted in the provisions of current performance-based seismic design. In this study, component deterioration after local buckling of steel beam and columns is incorporated in dynamic analysis of existing high-rise steel moment frames subjected to long period ground motions. Performance-based earthquake damages are numerically investigated and compared in terms of the extent and distribution of plastic deformation ratios in beam and column components. Analytical results indicate that the characteristics of synthetic long period ground motions excited significantly different plastic deformations over the height of building structures. The component deterioration is not influential to the maximum responses of plastic deformation under the original scale of seismic excitations. The plastic deformation ratio of beams initiate and grow from the mid- floors, and the exterior connections sustained excessive damages.
Ultimate Capacity Calculation Method of Concrete Box Girder under a Given Load Condition
Authors: Xu Dong , Zhang Yu
Published: July 2016

Traditional method in the current codes for ultimate capacity of shallow beams is based on a selected section and a specific force condition, such as flexural capacity of mid-span section, shear capacity of Fulcrum section. The behaviour of concrete box girder is complicated, especially for its spatial effects, so traditional method is lack of accuracy. Given that concrete box girder is composed of a series of concrete slabs subjected to global effect (in-plane membrane effect) and local effect (out-of-plane bending), a new ultimate capacity method based on “plate element” is proposed. Based on layered sectional method, “plate element” can be subdivided into several “membrane elements” along the thickness direction. The ultimate capacity of the “plate element” can be deduced through a non-linear program. The new ultimate capacity method will promote the safety and sustainability of concrete box girder.
Validation of Dynamic Increase Factors in Structural Design Codes
Authors: Yu Yong Jae , Cho Jae-Yeol
Published: July 2016

In the design of structural concrete for impact loading, design or model codes often employ a dynamic increase factor (DIF) to impose dynamic effect on static response. DIF that are obtained from material test results and that are currently adopted design codes like ACI 349M-06, fib Model Code 2010 and ACI 370R-14. However, DIFis too simple and limited to consider a variety of properties of materials, their application in practical design is questionable. In this study, DIF used in these three codes were validated through the finite element analysis of reinforced concrete (RC) and prestressed concrete (PSC) slab which were tested by other researcher. Consequently, it was found that DIF has great effect on the behavior of the structures so that selection of DIF should be very careful.
Linking Innovative Design to the Education for Structural Engineers
Authors: Hong Namhee-Kim , Koh Hyun-Moo , Hong Sung-Gul
Published: July 2016

Many engineering students by this time have been directed to focus more on technical enhancement in depth while not paying much attention to other factors such as structural art. However, such traditional education paradigm is now facing to be restructured due to the change of surrounding circumstances such as high level of expectation for design, strong power of new digital technology flowing over design. The authors have conducted a series of educational design programs to develop a new education paradigm that meets the demanding design requirements. Considering conceptual design as a positive opportunity for collaboration work, conceptual design competitions and academy have been provided to multi-disciplinary students. To link the way of innovative design to education, the birth of previous innovative design cases has been first overviewed specifically focusing on what sources were the motivations and how they are acclaimed. Then, the study on education paradigm toward innovative design was done to establish a basis of an education program. Focusing on a group generation of ideas or solutions to a problem, a phase-oriented approach for creativity and brainstorming with the participants from different perspectives have been applied for the design of education program for innovative structural design. The education program was further refined by addressing major aspects: (1) depth of conceptual design; (2) perspectives for curriculum; (3) visual communication tool among multi-disciplinary participants;

(4) the way of collaboration work; and (5) feedback from professionals.
Study on Pre-camber Setting of Continuous Steel Truss Girder Bridge
Authors: Li Jiali , Zhang Xiedong
Published: July 2016

The setting of the pre-camber is influenced by lots of factors. Normally, the pre-camber of steel truss girder is set by changing the length of the top chords, which leads to high local stress located between the upper chords and endangers structural stability. In order to obtain ideal pre-camber setting, this paper puts forward a new method to set it by only changing the length of inclined chords, an optimizing model, integrally considering theoretical pre-camber, additional counterforce and stress, is established by applying nonlinear-programming-based temperature rising-and- lowering method, whose optimal solution is solved by MATLAB software. Exampled by one three- span continuous steel truss arch bridge, the results show that, the new method is precise and functional, which can provide reference to similar bridges.
A Recommendation to the Application of Directional Combination Rules for the Seismic Responses in Bridge Design
Authors: Cao Yinghong
Published: July 2016

It is well known that the seismic forces applied in orthogonal directions should be combined to achieve the maximum seismic response of bridges. However, design codes do not give detail instruction to process the concurrent responses of seismic excitations when combined with other load effects in design. This leaves a few different algorithms by engineers’ own judgments when doing the load combinations in the bridge design. This paper investigated these algorithms and compared their distinctive differences in design process. Based on the fact that both orthogonal seismic waves can shake the bridge site simultaneously, a revised 30% rule is recommended in this paper to estimate the reasonable concurrent responses. This revised 30% rule essentially treats excitations in orthogonal directions as normal load cases and applies 1.0, 0.3 load factors to them in one scenario and 0.3, 1.0 factors in another, just like the same pattern we do with other load cases. Then, seismic responses can be combined with all concurrent responses from other loads cases using the load combination factors defined in the codes.
Eccentric-wing Flutter Stabilizer for Bridges
Authors: Starossek Uwe
Published: July 2016

A device is presented that aims at preventing bridge flutter. It consists of wings positioned along the sides of, and fixed relative to, the bridge deck. Flutter suppression efficiency is high provided the lateral eccentricity of the wings is large. It is a passive aerodynamic device that is more economical than other passive measures or devices. Moreover, it does not contain moving parts. This is an advantage over devices with moving parts that meet resistance due to reliability concerns. Results of a numerical study are presented in which the critical wind speed for flutter onset of a bridge without wings and with wings mounted in various configurations were determined. Preliminary wind tunnel test results are reported and a cost estimate is given.
Performance Based Optimal Human Comfort Design of Toggle-Brace-Damper System for Super Tall Buildings
Authors: Ma HaoJia , Zhao Xin
Published: July 2016

With the increase of building height, the super tall building structure will be flexible and slim. The structural natural frequency of super tall building is quite close to the predominant frequency of strong wind, and the building acceleration induced by wind load become increasingly prominent. The toggle brace damper system has been proved to be an effective motion amplification device, which can amplify the damper displacement under wind load, and can thus improve the efficiency of the viscous dampers dramatically. In this paper, a new optimal design method for finding the optimal placements, number and parameters of toggle brace dampers is proposed for satisfying human comfort performance requirements under wind loads. The theoretical basis and design process for finding optimum geometry parameter and damping coefficient of the toggle brace damper system are also developed. A real 250 meter super tall residential building project will be employed to illustrate the effectiveness and applicability of the proposed performance based optimal human comfort design method of toggle brace dampers for super tall buildings.
Gerald Desmond Bridge – Challenges and Solutions for Vibration Control
Authors: Carter Matt , Yeung Ngai
Published: July 2016

Gerald Desmond Bridge replacement is a 305m mainspan cable stayed bridge which is under construction and will become California’s first long span cable stayed bridge, and form a distinctive landmark in Los Angeles with its elegant mono-pole towers with a unique section transforming from an octagon to a diamond. The total length of the replacement is about 3km long including 2km elevated approach viaducts built with prestressed concrete box sections.

The cable stayed main bridge carries six lanes of traffic and a bikeway attached to the edge girder with cantilever beams. The challenges of a durable solution for dynamic effects induced by seismic events, winds and traffic have been resolved by an intelligent solution with dampers and fuses. This paper focuses on the issues of aerodynamic instability during construction and in service, wind induced and vehicle induced vibrations and pedestrian comfort. Wind tunnel studies are discussed for the free standing tower during construction, full-cantilever erection stage, in-service with traffic, post-earthquake damages and behaviours with traffic. Rain and wind induced and vehicle induced stay cable vibrations, bikeway vibrations due to traffic on main girder and people running and jumping on the bikeway are also studied. The design covers a full checking of the bridge vibration and control for various stages and loading conditions, and proves the sustainable design for a high performance bridge.
Flutter Stability Studies of Long Span Bridge with Active Control Wing Plate by CFD Numerical Simulation
Authors: Zhan Hao
Published: July 2016

Long span suspension bridges, due to their flexibility and lightness, are much prone to flutter instability. A relatively new research area on aerodynamic stability for very long span bridges is based on actively controlled flaps attached along the girders. Different from previous research, this paper proposes a new method to study the question. By secondary development of commercial computational fluid dynamics software FLUENT, the paper establishes two-dimensional bending and torsional fluid-structure interaction numerical model to study flutter stability of a long span suspension bridges with active control wing plate which is located beneath the deck. The paper study the flutter stability by controlling the rotational velocity of the wing plates with respect to that of the bridge deck. Numerical results show: The flutter critical wind speed of girder without wing plate is agreement with wind tunnel test. It is an optimal control law that the leading surface rotates in the opposite direction and the trailing surface rotates in the same direction with respect to the deck motion. The maximum torsional displacement amplitude decrease when increasing the rotational velocity of the winglet with respect to that of the deck.
Laser Ultrasonic Experimental Study on the Propagation of Acoustic Emission Signals in Steel Wires
Authors: Nie Dan , Sun Limin , Jiao Sheng
Published: July 2016

To form the basis for acoustic emission(AE) monitoring of bridge cables, laser ultrasonic study on steel wires is conducted in this paper. Ultrasonic testing is first performed on a single wire. The experimental dispersion curves are then compared with those derived using elastic wave propagation theory in a rod, and good agreement is found, suggesting the potential of this experimental technique for investigating acoustic emission in steel wires particularly for cases when the analytical solution is not available. Hence subsequent experiments are conducted on two contacted wires where the variation of propagation properties of guided waves caused by the interaction between the two strand wires is focused. With the help of improved two-dimensional Fourier Transform, the results reveal new modes of guided waves in two strand wires in contact, which means the two strand wires become a new waveguide different from a single wire because of the close contact.
Numerical Investigation on the Effects of Local Damage to the Dynamic Properties of Buildings Using Limited Vibration Data
Authors: Caringal Kristian , Oreta Andres
Published: July 2016

The challenge in structural health monitoring and damage detection is how to use the limited number of sensors on a building to assess the condition of the structure at any point in time. A case study simulating application of different levels of isolated local damage to the different floors were done to determine the corresponding dynamic properties and to observe the sensitivity of the dynamic properties to local changes using a several shear building models. Dynamic condensation was also applied to the model to portray limited vibration data.The results from the condensed 2 DOF model resulting into the two lowest natural frequencies in the structure can only be used in detecting the damage from the first unto the fifth floor in the building. With that, a change of 5% in the frequency can mean up to a 50% local damage to the stiffness in a single floor. These findings can be used to estimate the damage present in a building and provide warning signals for the building owner.
From Aerial Photography to 3-Dimensional Inspection of Bridges
Authors: Hallermann Norman , Morgenthal Guido
Published: July 2016

Bridges take an exceptional key role in our infrastructure system. In regard to the inexorable progress of ageing respectively deterioration of our existing bridges and the simultaneously continuous increasing volume of traffic the inspectionand monitoring plays an increasingly important role in providing a safe infrastructure system. Conventional inspections of bridges are based on intensive visual investigations performed by special trained proof engineers. These inspections are quiet complex. Data capturing processes and the documentations of inspection result are time consuming, often incomplete, not time referenced or not directly referenced to the location on the structure. This paper presents an aerial image based approach using professional unmanned aerial system (UAS) for a thorough inspection for an efficient monitoring of bridges.
Prediction and Estimation of Vessel Movement Parameters Based on Video Monitoring
Authors: Ji Zhaning , Sun Limin
Published: July 2016

Video monitoring as an important part of bridge health monitoring is getting more and more attention in practice. The acquirement of vessel movement parameters through video monitoring is a practical but challenging problem encountered in the engineering field. An approach combining kalman filtering with iteration algorithm was proposed to practically predict and estimate the vessel movement parameters using the monitored spatial data of vessels. The vessel state vectors are obtained through moving object tracking method based on optical flow. Numerical simulations as well as practical analysis are demonstrated to verify the accuracy and feasibility of the proposed approach. The results indicate that the proposed approach can accurately predict and effectively estimate movement parameters of vessels.
Research on Mechanical Properties of New Orthotropic Steel Bridge Deck
Authors: Wu Wenqing , Liu Yulong , Zhang Xian , Song Xiaodong , Tang Zhangxiang , Yang Yan
Published: July 2016

Aiming to resolve two main distresses of traditional orthotropic steel bridge deck such as the welding fatigue crack and the premature damage of pavement, this paper proposes a new kind of orthotropic steel bridge deck based on corrugated steel plate. The fundamental elements of this new deck include a steel plate in the upper layer, a corrugated steel plate in the middle layer which give a role of U-type rib in the traditional bridge deck, and a steel plate in the lower layer. Besides the fundamental structure of steel deck, a thin layer of reactive power concrete (named as RPC) is conceived to be paved on the steel deck. This paper mainly analyzes the mechanical properties of this new deck such as the transverse load transfer path and the hot spot stress, the mechanical properties comparison is also completed between this new orthotropic steel deck and the traditional one. The research shows that the mechanical properties of global deformation and local stress for the new orthotropic steel deck are much advanced than the traditional one.
New Assessment Method on Shear Resistance of Perfobond Shear Connectors in Steel-Concrete Composite Structure
Authors: Wei Xing , Li Yadong
Published: July 2016

The behaviour of shear connectors will have a major impact on the global behavior of steel-concrete composite structure. Perfobond shear connector has been developed during last two decades and has become popular due to their advantageous properties. Longitudinal shear strength is considered as a major constraint in the design of composite structure and it can be assessed by expensive and time consuming experimental techniques. Longitudinal shear resistance of perfobond shear connectors is depends on some design parameters. In this paper, considering its powerful prediction ability on nonlinear problem, artificial neural networks was induced to investigating and a new intelligent evaluation method on shear resistance of perfobond shear connectors was proposed. Choosing the diameter of holes, the yield strength of steel plate, concrete compressive strength, the ratio of transverse rebar, depth of steel plate and thick of steel plate as input values, Back Propagation Neural Networks (BPNN) model was developed for determination of the longitudinal shear resistance of perfobond shear connectors. It is demonstrated that, with the same design parameters as test specimens, the longitudinal shear resistance generated by the BPNN model is quite close to test result after proper training of the BPNN. Furthermore, Instead of three-dimensional FEM Analysis or Push-out test, the BPNN model is computationally efficient tool used to predict shear resistance of perfobond shear connectors in different parameters..
Effects Of Partially Unbonded Tendons on Seismic Behavior of Precast Concrete Bridge Piers
Authors: Shim Chang-Su , Koem Chandara , Lee Sang-Yong , Park Sung-Jun
Published: July 2016

Recently, seismic action on infrastructures is one of the major concerns, which causes extreme collapse and huge destruction. An advanced high-performance seismic resisting system for bridge substructure is recommended with adopting precast system technology to obtain particularly earthquake resistance, construction time saving, cost elimination, and environmental impacts. A new design concept of precast bridge columns was suggested. Quasi-static tests and nonlinear finite element analyses were conducted to evaluate seismic response of precast segmental bridge piers. The parametric study considered an initial prestressing force, unbounded length of the tendons at the joints, and details of axial steels. The finite element model is elaborated and utilized to assess the behavior of precast columns under seismic load. Concrete damage plasticity and bilinear model represented the mechanical behavior of concrete, reinforcement, prestressing tendon respectively. Partially unbonded tendons in precast columns provided stable ductile behavior after reaching maximum load capacity of the column.
Development of Probabilistic Temperature Loadsfor a PC Bridge in Oklahoma
Authors: He Jun , Wang Naiyu , Muraleetharan K. K.
Published: July 2016

Temperature effects have always been considered to be one of the critical issues that affect the performance of traditional PC bridges. In order to develop an efficient temperature loading model for predicting bridge temperature-induced response, numerical and analytical studies were conducted on a PC girder bridge in Oklahoma. Firstly, a heat transfer model was established with hourly climate input data to estimate the temperature distribution and compared with monitoring counterparts. Secondly, probabilistic models of temperature loading were proposed based on environmental conditions from the 20-year climatic data and heat transfer analytical results. Finally, and the temperature loading values for a 75-year return period were determined and compared with recommended values in AASHTO LRFD(2012). The proposed temperature loading model can be referred to aid engineers in predicting the thermal behaviour of PC girders in Oklahoma.
Fire of Steel Plate Girder Bridge With an Orthotropic Deck
Authors: Zobel Henryk , Karwowski Wojciech , Wróbel Marcin
Published: July 2016

A huge fire on Lazienkowski Bridge across Vistula River - one of the most important bridges in the center of Warsaw – capitol of Poland occurred on 14 of February 2015. The bridge was built in 1972-74as full steel structure with three wooden service decks between girders. It consisted of five four girders continuous spans 76,5+90,0+90,0+90,0+76,5 m. The fire started during the exchanging of these wooden elements under the first span. It started in the afternoon and was extinguished next day in the morning. During that time three spans were under fire. Extensive investigation and analysis were done during next 6 weeks including material investigation, geometrical verification of steel superstructure and FEM model analysis to determine the behavior of bridge during thermal overloads. Following results are presented in the paper i.e. local deformation of the deck and webs of the girders, global rotation of the outer girders and global displacement of the all four girders (also due to bearing and expansion joints behavior).
Bridge Deck Waterproofing on Steel
Authors: Uebelhoer Dirk
Published: July 2016

Bridges are critical structures for infrastructure. ISO 12944, 1-8, is the worldwide recognized standard for corrosion protection of structural steel and is also valid for bridge structures. The 8 parts of this standard cover different items, however parts 2 & 5 are most important for preservation, but it’s difficult to find standards for the protection and refurbishment of bridge decks. Bitumen based state of the art systems cannot fulfil the increasing requirements for modern bridges, when it comes to extended service life and resistance to severe stresses, so developing new resin based systems which can provide a longer service life, shorter down times in case of maintenance works and reduced repair costs are the main target for system manufacturers. The introduction of 2new systems, with excellent physical properties, is shown in this paper.
Carbon and Concrete – The Future of Construction
Authors: Schladitz Frank , Curbach Manfred , Tietze Matthias , Lieboldt Matthias
Published: July 2016

Concrete is a multifunctional construction material and currently the most employed one. Buildings built with reinforced concrete can provide excellent structures. However, current reinforced concrete constructions have a drawback – steel in concrete can corrode and can cause significant damage. To prevent this, concrete, dependent on its ambient surrounding, has to be protected by a thick concrete cover. This leads to a high material, resource and energy consumption and notable carbon dioxide emissions. Furthermore, the service life of reinforced concrete is still limited to 40 to 80 years.

For decades, an alternative to steel reinforcement has been searched for. In Germany, the focus has been laid on non-metallic reinforcements such as glass and carbon. In the 1990s, basic research has begun in the field of textile reinforcement and shown very promising results. For 10 years now the material has been slowly transferred into practice.

For German companies and research institutions as well as the German government there is a future in carbon reinforced concrete – a further development of textile reinforced concrete (TRC). Carbon reinforced concrete shall be used for new constructions and for the strengthening of existing structures. Germany wants to build more sustainable and energy-efficient in the future and wants to reduce quickly the existing investment backlog. The market launch shallbe quick and extensive.

However, there are still numerous conditions that need to be established, e.g. thicker cross sections, suitable connection devices, economic production processes and appropriate guidelines. To set up these conditions, Germany is currently investing about 65 million euros(45 million euros public funds plus around20 million euros company funds) in the quick exploration of the material and anew construction design.More than 130 companies and research institutions from different industrial sectors participate in the currently largest research project C3 – Carbon Concrete Composite in the building industry. The aim is to establish all necessary conditions in order to widely apply the new construction design by 2020.

This paper provides an insight into the topic carbon reinforced concrete, the overall research project and all ongoing particular projects