Structural Engineering Commons^™

Monotonic And Cyclic Response Of Single Shear Cold-Formed Steel-To-Steel And Sheathing-To-Steel Connections, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Monotonic and cyclic backbone load-deformation response models for single shear steel-to-steel and plywood, oriented-strand board, and gypsum board sheathing to cold-formed steel screw-fastened connections are developed with support from an experimental program. Connection strength, stiffness, and the probability of screw shear failure are correlated to fastener bearing strength of the two connected plies. Cyclic strength and stiffness degradation was negligible. Cyclic excursions resulted in increased connection stiffness from the screw bearing hardening the ply material and locking in the plies.

Super Thin Ultra-Light Posttensioned Flat Plate Floor Systems For Affordable Urban Housing, Zuzanna Sobczak

Research Opportunities for Engineering Undergraduates (ROEU) Program 2016-17

The objective of this research is the development of super thin ultra-light post-tensioned flat plate floor systems by using high performing ultra-light cementitious composites that lead to slender, sustainable structures to remove the limitations imposed by commodity materials on mid- and high-rise construction. This objective will be achieved by investigating the full-scale behavior of these super thin floor systems using high fidelity finite element analyses in terms of flexure, punching shear, long term deflections, and vibrations.

Inspire Newsletter Summer 2017, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.

Shape Memory Alloy Reinforced Concrete Frames Vulnerable To Strong Vertical Excitations, M A. Elfeki, Maged A. Youssef

Civil and Environmental Engineering Publications

Reinforced concrete (RC) framed buildings dissipate the seismic energy through yielding of the reinforcing bars. This yielding jeopardizes the serviceability of these buildings as it results in residual lateral deformations. Superelastic shape memory alloys (SMAs) can recover inelastic strains by stress removal. This paper extends previous research by the authors that optimized the use of SMA bars in RC frames considering the horizontal seismic excitation by addressing the effect of the vertical seismic excitation. A steel RC six-storey building designed according to current seismic standards is considered as case study. Five different earthquake records with strong vertical components are …

Ductile Corrosion-Free Gfrp-Stainless Steel Reinforced Concrete Elements, Maged A. Youssef, Mohamed E. Meshaly, Ahmed Elansary

Civil and Environmental Engineering Publications

Corrosion of steel rebars is known to cause deterioration of concrete structures that can lead to catastrophic failures. To mitigate this problem, steel rebars can be replaced with Glass Fiber-Reinforced Polymer (GFRP) rebars. However, the lack of ductility of GFRP-reinforced elements has prevented their use in many structural applications, especially in seismic areas. Stainless Steel (SS) rebars are corrosion resistant and have adequate energy absorption and ductility. However, they are much more expensive than steel rebars. This paper proposes the combined use of SS and GFRP rebars to achieve ductile and corrosion-free elements. The first challenge for such a proposal …

Restrained Shrinkage Of Fly Ash Based Geopolymer Concrete And Analysis Of Long Term Shrinkage Prediction Models, Md R. Islam, Mahbub K. Ahmed, Hosney Ara Begum, Erez N. Allouche

Journal of the Arkansas Academy of Science

The research presented in this manuscript describes the procedure to quantify the restrained shrinkage of geopolymer concrete (GPC) using ring specimen. Massive concrete structures are susceptible to shrinkage and thermal cracking. This cracking can increase the concrete permeability and decrease the strength and design life. This test is comprised of evaluating geopolymer concrete of six different mix designs including different activator solution to fly ash ratio and subjected to both restrained and free shrinkage. Test results obtained from this experimental setup was plotted along with the available empirical equation to observe the shrinkage strain of GPC and a model was …

Effects Of Mechanical Bar Splices On Seismic Performance Of Reinforced Concrete Buildings, Abdullah Al Hashib

Electronic Theses and Dissertations

Mechanical bar splices, which are commonly referred to as couplers, are currently used in reinforced concrete structures to directly connect steel bars in lieu of conventional lap splicing. With proper detailing, couplers can be utilized to connect precast beams and columns to accelerate the construction. However, the experimental and analytical studies regarding their effect on the performance of RC moment-resisting frames (MRFs) are scarce. Current ACI 318 restricts the use of couplers in plastic hinge regions of special moment-resisting frames (SMRFs). Nevertheless, they can be incorporated at any location of the intermediate and ordinary MRFs. The seismic performance of RC …

Compact Facility For Testing Steady And Transient Thermal Performance Of Building Walls, Aimee Byrne, Gerard Byrne, Anthony Robinson

Articles

Energy efficiency retrofit of buildings represents a key effort in reducing EU energy demand by 20% by 2020. However, predictions tend to overestimate savings by large percentages. The shortfall in savings can be attributed to incorrect predictive techniques, comfort takeback along with other behavioural and workmanship variables. Common predictive techniques related to heat loss tend to be based on the U-value of the building envelope. This paper presents the design of a more straightforward and compact version of the traditional Hot-Box apparatus (measures U-value) which instead determines the thermal resistance of samples of building envelope. U-value includes the need to …

Limited Bandwidth Wireless Communication Strategies For Structural Control Of Seismically Excited Shear Structures, Benjamin Winter

Dissertations, Master's Theses and Master's Reports

Structural control is used to mitigate unwanted vibrations in structures when large excitations occur, such as high winds and earthquakes. To increase reliability and controllability in structural control applications, engineers are making use of semi-active control devices. Semi-active control gives engineers greater control authority over structural response versus passive controllers, but are less expensive and more reliable than active devices. However, the large numbers of actuators required for semi-active structural control networks introduce more cabling within control systems leading to increased cost.

Researchers are exploring the use of wireless technology for structural control to cut down on the installation cost …

Investigating Composite Action At Ultimate For Commercial Sandwich Panel Composite Connectors, Salam Al-Rubaye, Taylor J. Sorensen, Marc Maguire

Faculty Publications

To achieve full or partial-composite action in prestressed concrete sandwich panel walls, the engineer must obtain a percent composite action from a connector manufacturer, making some engineers uncomfortable. Engineers are dependent upon the recommendations given by the connector manufacturers to establish their designs. This project tested six full-scale sandwich panel walls to evaluate the percent composite action of various connectors and compare the results to those provided by the composite connector manufacturers. This study concluded that the reported degrees of composite action from each manufacturer are considered conservative in all instances for the connectors tested in this paper. Additionally, the …

Load Estimation, Structural Identification And Human Comfort Assessment Of Flexible Structures, Ozan Celik

Electronic Theses and Dissertations

Stadiums, pedestrian bridges, dance floors, and concert halls are distinct from other civil engineering structures due to several challenges in their design and dynamic behavior. These challenges originate from the flexible inherent nature of these structures coupled with human interactions in the form of loading. The investigations in past literature on this topic clearly state that the design of flexible structures can be improved with better load modeling strategies acquired with reliable load quantification, a deeper understanding of structural response, generation of simple and efficient human-structure interaction models and new measurement and assessment criteria for acceptable vibration levels. In contribution …

Analytical Strip Method For Thin Cylindrical Shells, John T. Perkins

Theses and Dissertations--Civil Engineering

The Analytical Strip Method (ASM) for the analysis of thin cylindrical shells is presented in this dissertation. The system of three governing differential equations for the cylindrical shell are reduced to a single eighth order partial differential equation (PDE) in terms of a potential function. The PDE is solved as a single series form of the potential function, from which the displacement and force quantities are determined. The solution is applicable to isotropic, generally orthotropic, and laminated shells. Cylinders may have simply supported edges, clamped edges, free edges, or edges supported by isotropic beams. The cylindrical shell can be stiffened …

Site Specific Sinkhole Risk Assessment In Central Florida Using Cone Penetrometer Testing, Ryan Shamet

Electronic Theses and Dissertations

As Florida's population is expanding and greater fluctuations in groundwater levels are being recorded, Central Florida has been experiencing a higher frequency of sinkhole occurrences than ever before in recorded history. Sinkholes in Central Florida are formed by a combination of bedrock weathering and overburden soil erosion due to the groundwater recharge and are a part of Florida's past and future geology. The initial stage of a sinkhole is referred to as soil raveling and is the most effective time to perform soil improvement measures, such as grouting, to mitigate further expansion of a subterranean void. Subsurface exploration tests, commonly …

Air Injection As A Scour Countermeasure At Bridge Piers, Ravi Teja Reddy Tippireddy

Dissertations, Master's Theses and Master's Reports

Local scour is a major cause of concern for the stability of bridge piers and the safety of the public using the bridges. Structural countermeasures and flow-altering devices have been developed to deal with local scour. Many armoring structural countermeasures are very effective and efficient in clear water conditions but are susceptible to moving bed forms and leaching. The flow-altering devices are effective in both clear water conditions and moving bed forms, but are prone to clogging, less efficient in changing flow direction, etc. This study aims to reduce the local scour by injecting air in order to reduce the …

Detection Of Fatigue Damage In Shear Connections Using Acoustic Wave Propagation, Zichao Wang

Dissertations, Master's Theses and Master's Reports

Fatigue damage is an important concern in structural steel connections where frequent load reversals are expected. Detection of fatigue damage is typically done with infrequent visual inspections that are subjective and limited to surface features. A permanent embedded structural health monitoring (SHM) system could be helpful in detecting damage as it occurs. Current methods for detecting fatigue damage include inference of fatigue life expended through cycle counting from long-term strain measurement campaigns, and through short-term impedance measurements. The first approach has the advantage that it is relatively simple from an algorithmic point of view, but it is an indirect measure …

Uav-Based Bridge Inspection And Computational Simulations, Luis Duque

Electronic Theses and Dissertations

The use of Unmanned Aerial Vehicles (UAV), commonly known as drones, has significantly increased in the field of civil engineering due to the poor condition of the United States’ infrastructure. The American Society of Civil Engineers (ASCE) recently reported that more than 9.1% of the United States’ bridges were structurally deficient and required attention and maintenance to ensure appropriate structural performance. Meanwhile, current practices are expensive and unsafe for bridge inspectors, requiring innovative and safer methods for the study of bridges. The goal of this paper was to identify better techniques to not only inspect, quantify, and determine the effect …

Percy H. Perkins, Jr. Architectural Drawings, Zach S. Henderson Library Special Collections

Finding Aids

This collection consists of materials relating to author and gemologist Percy H. Perkins. Materials span 1923 to 1985, and consist of architecture drawings for various significant buildings in southeast Georgia, including a six room schoolhouse in Claxton, GA, Pembroke State Bank, the Stadium & Athletic Field for Morris Brown College, the Women's Dormitory School for Officers’ Training at The Salvation Army Headquarters, Bacon County Elementary School, Claxton High School, and Evans County Training School.

Find this collection in the University Libraries' catalog.

Enhancing Ductility Of Wwr Slabs, Mohamed Shwani, Taylor J. Sorensen, Ethan Pickett, Parker Syndergaard, Marc Maguire

Faculty Publications

A series of research studies have recently identified an issue called strain localization in welded wire reinforced (WWR) members. This phenomenon reportedly concentrates strains at welded cross wire locations and severely limit ductility. Those that identified the phenomenon used it to imply that WWR is unsafe because it does not warn of failure. This research program is investigating details to mitigate the strain localization effect and demonstrate the WWR can be used safely. Sixteen beams have been constructed using WWR and rebar with various cross wire spacing, using a realistic design. The strain localization phenomenon was not demonstrated, but WWR …

Linking Geospatial Engineering Into Collaborative Multidisciplinary Bim Projects - An Educational Perspective, Avril Behan, Helen Murray, Jonathan Argue, Ronan Hogan, Audrey Martin, Pat O'Sullivan, Robert Moore, Malachy Mathews

Conference papers

This paper describes the background to and execution of a postgraduate project undertaken by students on DIT's MSc in Geospatial Engineering (GeoEng) in support of a project on level 2 BIM being undertaken by students on the MSc in applied Building Information Modelling & Management (aBIMM) around the retrofit of and new build extension to the Grangegorman Clock Tower Building. In support of this requirement, an external and internal survey of the existing structure and its surrounding topography was required. The aBIMM students and staff acted as the Design Team who subcontracted the Geo Eng group who were organised into …

Inspire Newsletter Winter 2017, Missouri University Of Science And Technology. Inspire - University Transportation Center

INSPIRE Newsletters

No abstract provided.

Optimising The Performance Of Cement-Based Batteries, Aimee Byrne, Shane Barry, Niall Holmes Dr., Brian Norton

Articles

The development of a battery using different cement-based electrolytes to provide a low but potentially sustainable source of electricity is described. The current, voltage, and lifespan of batteries produced using different electrolyte additives, copper plate cathodes, and (usually) aluminium plate anodes were compared to identify the optimum design, components, and proportions to increase power output and longevity. Parameters examined include water/cement ratio, anode to cathode surface area ratio, electrode material, electrode spacing, and the effect of sand, aggregate, salts, carbon black, silica fume, and sodium silicate on the electrolyte. The results indicate that the greatest and longest lasting power can …