4th World Congress and Exhibition on Construction and Steel Structure 2017-10-16 October 16-18, 2017 Atlanta, USA

Amr S Elnashai is the Vice Chancellor/Vice President for Research and Technology Transfer at the University of Houston, USA. He was previously Dean of Engineering at the Pennsylvania State University, USA, and the Harold and Inge Marcus Endowed Chair in Engineering. Before serving at Pennsylvania State University, he was Head of the Civil and Environmental Engineering Department at the University of Illinois at Urbana-Champaign and the Bill and Elaine Hall Endowed Professor. He is a fellow of the UK Royal Academy of Engineering and fellow of the American Society of Civil Engineers as well as the UK Institution of Structural Engineers. He authored/co-authored over 145 journal publications and 4 books and many other reports and publications. He advised 45 PhD students to graduation, and over 100 MS thesis students.

Earthquakes are often followed by fires, which compound the damage inflicted by ground shaking and subject the affected population to further increased risk to lives and livelihoods. Insights would be obtained into the safety of the building stock subject to combined earthquakes and fire scenarios if models existed exhibit the versatility of sequential analysis of main earthquake-fire-aftershock ground motion. Such a system is described in this presentation. The advanced inelastic dynamic analysis platform ZEUS-NL is extended to conduct thermal stress analysis after large deformations and damage have been suffered by the structure. The deformed shape at the end of the earthquake is used as the initial condition for subjecting the structure to non-uniform temperature gradients that are varying with time. This second analysis may also be followed by another dynamic analysis under the effect of earthquake aftershocks. Examples of application are provided from previous earthquakes as well as experimental investigation. The tool presented is an open-source advanced analysis code that is available

for use worldwide.

Gilbert A Hegemier recieved his PhD from the California Institute of Technology (Caltech) in Solid Mechanics and Structures. He currently serves as Distinguished Professor of Structural Engineering at the University of California, San Diego (UCSD) where he initiated the formation of the Department of Structural Engineering, guided the development of UCSD’s unique large-scale test facilities, and there he also serves as Associate Director of the Center for Extreme Events Research (CEER). His research areas include large-scale laboratory experiments, field testing, and computational analysis of civil structures subject to dynamic loading events such as blast, impact, and seismic. He has published over 100 journal papers on these topics and is an internationally recognized expert on protective technologies for civil structures.

Cold-formed steel (CFS) framed construction can offer considerable economic and performance advantages for certain structures subject to extreme events such as seismic, fire, and blast. Examples include mid-rise buildings in high seismic regions such as the western United States, and blast resistant modules (BRMs) for protection of personnel and equipment against accidental and man-made explosive threats. Structural systems of this type consist of light-gauge framing (e.g, studs, tracks, joists) attached with sheathing materials (e.g, composite panels in the form of gypsum or other cement-based material bonded to a layer of sheet steel). CFS-framed strucures can lead to lower installation and maintenance costs than other structural types, particularly when erected with prefabricated assemblies. They are also durable, formed of an inherently ductile material of consistent behavior, light weight, and can be manufactured from recycled materials. Compared to other lightweight framing solutions, CFS is non-combustible, an important characteristic to minimize fire spread. Although CFS-based strucural systems offer potential adavantages, the state of understanding regarding their behavior in response to extreme events, such as those noted previously, remains relatively limited. In an effort to improve this situation, a series of research collaborations, led by the University of California, san Diego (UCSD), between academia, government and industry were formed and two major programs were executed. In one, a full-scale six-story CFS wall braced building was constructed and subject to earthquake and fire testing via the world’s largest outdoor shake table- the Large High Performance Outdoor Shake Table (LHPOST) at UCSD. In the other, CFS-based BRMs were fabricated and subject to blast events via UCSD’s unique Blast Simulator and full-scale live explosive field tests. This keynote address describes these programs and their results.

C T Liu recieved his PhD from Brown University, USA in Materials Science and Engineering. He currently serves as Distinguished Professor in College of Science and Engineering at the City University of Hong Kong. His research areas include physical metallurgy and mechanical behaviour of metals, alloys, nanostructure materials, intermetallic compounds and bulk amorphous alloys, microstructure and phase transformation, alloy design of high-temperature structural materials, precious metal alloys, Ti-base alloys, metal-matrix composites and innovative material processing. He authored/co-authored over 135 journal publications and 26 books and many other reports and publications.

Recent studies have demonstrated that Fe-based alloys are perfect metallic materials for strengthening by a combination of nanoscale particles including nanoscale atomic clusters, intermetallics and carbides. This paper will summarize our recent study of computational aided design of ultra-high strength steels hardened by of uniform distributions of nanoscale particles in 2-10 nm. The precipitation processes are carefully controlled through the nucleation and growth in the alloys with controlled alloy compositions and heat treatments. Computational material calculations together with applications of the state-of-the-art micro-analytic tools are critical for the design of these multiple-component Fe-based alloys. The composition and morphology of these nanoscale particles have been characterized by detailed analyses of structural features obtained from atom probe tomography (ATP). The precipitation mechanism and sequence are found to be sensitive to some key elements in these alloys. Our results have demonstrated that the strength of nanostructured steels can reach to as high as 2000 MPa with a good tensile ductility and dimple-type fracture behavior. This series of nanostructured alloys have many important applications in transportation industries and energy conversion systems.

M Manikandan is the Senior Structural Engineer at Gulf Consult, Kuwait with responsibility for designing and construction consultation of the tall buildings, colleges, shopping complexes, multi-story car parks, hospitals, bridges and deep underground structures by considering the structural requirements and adequate constructible systems to complete the projects within allocated budget and time schedule. Prior to joining Gulf Consult, Kuwait, he has worked as a Structural Engineer at several companies, including RECAFCO, Kuwait, Saeed Hadi Aldoosary EST, Saudi Arabia, where he has completed many precast structures and treatment plants including the deep underground structures with heavy equipment. Notable, he is in the construction industry since past 15 years and has completed many land mark projects in Kuwait as well in Saudi Arabia. He has received his PhD in Risk Management in International Construction Projects as an External Part-time Researcher with Vels University, Chennai, India. He has received Civil Engineering degree from Kamraj University Madurai in 2000 and MBA in Project Management from Sikkim Manipal University, India in 2012. His professional interests focus on construction/project management, structural management and risk management in the construction projects. He has published 50 papers in international and national journals.

The use of concrete in high-rise buildings has increased significantly in the past 20 years mainly owing to improvement in all the technologies associated with these materials and methods related to prepare, supply and pour the concrete. Cementations materials, admixtures, aggregates, pumping techniques, transportations and elevation methods, etc. all these enchased possibilities are illustrated by taking 200 story high rise structural model; analyzed and designed by using the software ETABS-2013, to withstand the gravity loads and also the lateral loads considering Wind 100 mph, Exposure-Seismic Zone-I, soil profile type SD, Occupancy category 1.0 and Ductility factor, R=5.5. The type of ultra-high strength concrete cylindrical strength has been considered as 107 MPa at 28 days to bear the high load and straining action at lower portion of the core wall, steel sections and plates are confirming to ASTM-A992-Gr:70Ksi are considered for built-up column sections and floor

beams. In addition shear studs conforming to ASTM-A106-Gr:1020 with composite metal deck have also been considered to be have as rigid diaphragm to act as monolithic unit against the heavy lateral loads. This paper clearly show that the design and constructability considerations, serviceability requirements and international codes compliances such as ACI-318, ASCE-7, IBC-2011, UBC-1997, further, it proves that the combination of R.C.  concrete and steel composite sections could be the best solution for such tall skyscrapers.

Gintaris Kaklauskas is a Professor of Department of Reinforced Concrete Structures and Geotechnical Engineering and Director of Research Institute of Building Structures at Vilnius Gediminas Technical University (VGTU). He received his PhD and DrSc (Habilitation doctor) degrees from VGTU. He is Member of Lithuanian Academy of Science and recipient of ASCE best paper Moisseiff Award 2013, Lithuanian Science Prize 2013 and Marie Curie (Senior Research category) grant. He is Visiting Professor (under Fulbright fellowship) at University of Illinois, Urbana-Champaign. His research interests include service ability analysis and constitutive modeling of concrete structures.

The current study proposes a new concept of crack analysis of reinforced concrete (RC) members. The novel philosophy behind the proposed concept is to establish the mean crack spacing and width through the compatibility of the stresstransfer and mean deformation approaches by equating the mean strains of the tensile reinforcement defined analytical techniques. The concept considers primary cracks at the stage of stabilised cracking assuming that a single RC block of a length of the mean crack spacing represents the averaged deformation behaviour of the cracked member. Based on the experimental evidence, reinforcement strain within the block is characterized by a strain profile consisting of straight lines. The latter represent three different zones that are described by different bond characteristics. Crack spacing is defined as the sum of lengths of these zones within the length of the block. The proposed model involves the least amount of empiricism and is devoid of empirically established effective area of concrete. A preliminary statistical analysis of mean crack spacing using limited test data has demonstrated good predictive capabilities of the model resulting in 15% of the coefficient of variation. The proposed approach allows a critical assessment of the classical bond theory in regard to its fundamental statement relating crack spacing to Ø/pef ratio. A preliminary study has shown that the larger are the member’s section depth and the reinforcement ratio, the more the classical approach deviates from reality. It can be deduced that crack spacing is mostly governed by four geometrical parameters given in the order of importance: section height, reinforcement ratio, bar diameter and cover.