Using Acoustic Emission To Quantify Freeze–Thaw Damage Of Mortar Saturated With Nacl Solutions,
2014
Columbia University
Using Acoustic Emission To Quantify Freeze–Thaw Damage Of Mortar Saturated With Nacl Solutions, Ye Qian, Yaghoob Farnam, Jason Weiss
International Conference on Durability of Concrete Structures
Mortar samples were saturated with NaCl solutions of various concentrations and subjected to freeze– thaw cycles. Passive and active acoustic emission (AE) testing was conducted. The freezing temperature of the NaCl solutions in mortar corresponded with the sudden observation of passive AE events. The acoustic energy and damage parameter were calculated to evaluate the extent of freeze–thaw damage. The influence of the NaCl solution concentration and whether the solution freezes on freeze–thaw damage are discussed.
Physical Model And Mesoscale Simulation Of Mortar And Concrete Deformations Under Freeze–Thaw Cycles,
2014
Hokkaido University
Physical Model And Mesoscale Simulation Of Mortar And Concrete Deformations Under Freeze–Thaw Cycles, Fuyuan Gong, Evdon Sicat, Yi Wang, Tamon Ueda, Dawei Zhang
International Conference on Durability of Concrete Structures
The degradation of concrete material under multiple freeze–thaw cycles is an important issue for structures in cold and wet regions. This paper proposed a physical and mechanical model to explain the deformation behavior observed in previous experiments, from internal pressure calculation to mesoscale simulation, and for both closed and open freeze–thaw tests. Three kinds of internal pressures are considered in this study: hydraulic pressure due to ice volume expansion, crystallization pressure, and cryosuction pressure due to liquid–ice interface. The hydraulic pressure model combines Power’s model with poromechanical theories, which can well explain the reverse phenomenon (from expansion to contraction) observed …
A Multi-Criteria Methodology For Measuring The Resilience Of Transportation Assets And Prioritizing Security Investments,
2014
Purdue University
A Multi-Criteria Methodology For Measuring The Resilience Of Transportation Assets And Prioritizing Security Investments, Michelle S. Dojutrek, Samuel Labi, J Eric Dietz
International Institute for Infrastructure Resilience and Reconstruction (I3R2) Conference
Transportation project prioritization uses performance measures that are related to the transportation asset, its operations, and its environment. However, in the state of practice, evaluation does not consider directly the likelihood of natural or man-made threats, the infrastructure resilience, or the consequences of the infrastructure damage in the event that the threat occurs. Thus, during the prioritization of investments, assets of low security do not receive the due attention they deserve. In defining security as the lack of risk of damage from threats due to inherent structure or functional resilience, this paper is based on the premise that the inclusion …
Motive And Conflict In The Disaster Recovery Process Of Housing Reconstruction In Sri Lanka After The 2004 Indian Ocean Tsunami,
2014
University of Tokyo
Motive And Conflict In The Disaster Recovery Process Of Housing Reconstruction In Sri Lanka After The 2004 Indian Ocean Tsunami, Chang Yeol Choi, Riki Honda
International Institute for Infrastructure Resilience and Reconstruction (I3R2) Conference
Normative solutions for the successful recovery from large-scale disasters have been presented by various researches, but implementation requires a long process, and mechanism for the process to continue is necessary. We consider the consistency among strategies of stakeholders such as government and NGOs. These players make a decision based on not only direct motive but various complex motives and interaction with other players. This paper considers interactive decision-making as a game among stakeholders. As a case to study, we analyze housing reconstruction project in Sri Lanka after the 2004 Indian Ocean Tsunami. There was relatively abundant financial support, but the …
Concrete Carbonation And Chloride Resistance Under Initial Hot Water Curing,
2014
China University of Mining and Technology - Xuzhou
Concrete Carbonation And Chloride Resistance Under Initial Hot Water Curing, Guo Li, Xiaoling L. Li, Rongrong R. Wei, Jianmin M. Du, Xiaosuo S. Wu
International Conference on Durability of Concrete Structures
Three concrete mix proportions were designed and prepared, respectively, such as fly ash concrete (abbreviated as “FAC”) with 30% fly ash replacement ratio of cement, fly ash, and slag concrete (abbreviated as “FSC”) with each of 20% fly ash and slag replacement ratio and ordinary Portland cement concrete (abbreviated as “OPC”) for the research of carbonation and chloride resistance of concrete under different initial hot water curing. Specimens with precuring were put into 20°C water tank for curing firstly until a certain compressive strength of 14 MPa reached after demolding, while specimens without precuring were put into 40, 60, and …
Coupled Sediment Yield And Sediment Transport Model To Support Navigation Planning In Northeast Brazil,
2014
Wayne State University
Coupled Sediment Yield And Sediment Transport Model To Support Navigation Planning In Northeast Brazil, Calvin Trebor Creech
Wayne State University Dissertations
Deposition of sediment (shoaling) in commercial waterways is a major obstacle to maintaining sustainable riverine transportation of bulk goods (primarily agricultural and mining commodities). The rate of aggradation of sediment in a waterway is directly related to both the rate of sediment erosion from upland and river bank sources (sediment yield) and the energy in the river to effectively transport the sediment through the waterway system (sediment transport). Historically, methods used for waterway development have included trial and error or rules of thumb associated with river training structures and chute cut-off canals or engineering of navigation locks and dams. More …
Field Tests And Numerical Modeling Of Vehicle Impacts On A Boulder Embedded In Compacted Fill,
2014
Pennsylvania State University
Field Tests And Numerical Modeling Of Vehicle Impacts On A Boulder Embedded In Compacted Fill, Lynsey Reese, Tong Qiu, Daniel Linzell, Edward O'Hare, Zoltan Rado
Department of Civil and Environmental Engineering: Faculty Publications
Landscape Vehicular Anti-Ram (LVAR) systems are a group of protective barriers, which are designed using natural materials (e.g., boulders) and have proven to both effectively protect sensitive structures against threats and be aesthetically pleasing. This paper presents two consecutive vehicular crash tests hitting the same single boulder embedded in AASHTO coarse aggregate fill. A LS-DYNA model was developed to simulate the field-scale tests, which were instrumented with high-speed cameras and pressure cells. A readily available truck model from the National Crash Analysis Center was modified and implemented in the LS-DYNA model. The boulder and surrounding soil were modeled using the …
Freeze Thaw Durability Of Internally Cured Concrete Made Using Superabsorbent Polymers,
2014
Purdue University
Freeze Thaw Durability Of Internally Cured Concrete Made Using Superabsorbent Polymers, Wesley A. Jones, W. Jason Weiss
International Conference on Durability of Concrete Structures
The use of superabsorbent polymers (SAPs) to produce internally cured concrete has been shown to be effective in reducing the potential for restrained shrinkage cracking of high performance concrete mixtures. However, not much is known regarding the freeze–thaw durability of concrete mixtures that incorporate SAPs for internal curing (IC). When SAP particles desorb (or partially desorb) the “water” (pore fluid) they contain for the purposes of IC, some believe that the void space created by these particles can provide enough empty voids to accommodate the additional volume caused by water expansion upon freezing. This paper investigates the freeze–thaw durability of …
Painted Rumble Stripes: Alternatives To Raised Pavement Markers (Rpms),
2014
The College of New Jersey
Painted Rumble Stripes: Alternatives To Raised Pavement Markers (Rpms), Thomas M. Brennan Jr, Stuart R. Mikey, Darcy M. Bullock
JTRP Posters
This poster highlights research completed by the Joint Transportation Research Program (JTRP) led by Darcy Bullock, Lyles School of Civil Engineering, Purdue University, for JTRP Project SPR-3528, "Alternatives to Raised Pavement Markers (RPMs)." The poster includes photos taken at a construction site on State Road 25 located near Shadeland, Indiana. The top photo demonstrates how the center line corrected a driver when snow covered to avoid oncoming traffic. Photo was taken on US 231 near Country Road 800 in Tippecanoe County.
2013-14 Indiana Interstate Mobility Summary,
2014
Purdue University
2013-14 Indiana Interstate Mobility Summary, Steve M. Remias, Howell Li, Darcy M. Bullock
JTRP Posters
These posters highlight the speed and mobility metrics on four of Indiana’s interstates (I-94, I-65, I-465, and I-70). The posters are part of the effort by the Indiana Department of Transportation to characterize mobility concerns on the statewide interstate system.
Co2 Sequestration In Cement-Based Materials During Mixing Process Using Carbonated Water And Gaseous Co2,
2014
Queen's University Belfast
Co2 Sequestration In Cement-Based Materials During Mixing Process Using Carbonated Water And Gaseous Co2, Jacek Kwasny, P. A. Muhammed Basheer, Mark I. Russell, William Doherty, Kieran Owens, Neil Ward
International Conference on Durability of Concrete Structures
This paper presents selected findings from a recently completed research project, aimed at the investigation of CO2 sequestration in cement-based materials during the early stages of hydration when the cement paste is being mixed. Portland cement pastes were carbonated during the mixing process, using both carbonated water and gaseous CO2, and their properties were compared to the control non-carbonated mix. All mixes were prepared in a purpose-designed chamber that permitted carbonated water and gaseous CO2 to be mixed with the cementbased materials during the mixing process, without losses of CO2 to the external environment. Temperature …
Striping Truck Utilization Project,
2014
Purdue University
Striping Truck Utilization Project, Jon R. Padfield, James Handy
JTRP Posters
This poster highlights research completed by the Joint Transportation Research Program (JTRP) led by Jon Padfield and James Handy, Purdue University for JTRP project SPR-3722, “Striping Truck Utilization for Crawfordsville and Greenfield District.” This poster highlights the transformation of striping trucks at both districts using Value Stream Mapping (VSM) through the Technical Assistance Program.
Bs News January/February,
2014
Technological University Dublin
Numerical Simulations Of Dynamic Behavior Of Polyurea Toughened Steel Plates Under Impact Loading,
2014
Purdue University
Numerical Simulations Of Dynamic Behavior Of Polyurea Toughened Steel Plates Under Impact Loading, Chien-Chung Chen, Daniel G. Linzell
Department of Civil and Environmental Engineering: Faculty Publications
The objective of the work discussed herein is to develop a nonlinear 3D finite element model to simulate dynamic behavior of polyurea toughened steel plates under impact loading. Experimental and numerical work related to model development are presented. Material properties are incorporated into numerical models to account for strain-rate effects on the dynamic behavior of polyurea and steel. One bare steel plate and four polyurea toughened steel plates were tested under impact loading using a pendulum impact device. Displacement time-history data from experimental work was used to validate the numerical models. Details on material model construction, finite element model development, …
Assessment Of Load Sharing Members In An Anti-Ram Bollard System,
2014
Hinman Consulting Engineers, Alexandria, Virginia
Assessment Of Load Sharing Members In An Anti-Ram Bollard System, Scott Kinney, Daniel Linzell, Edward O'Hare
Department of Civil and Environmental Engineering: Faculty Publications
Due to the increased frequency, scale, and danger of malicious attacks carried out by Vehicle Borne Improvised Explosive Devices (VBIEDs), anti-ram bollards have become a key element in the protection of critical structures. This study focused on the evaluation of above grade load sharing members in a steel anti-ram bollard system in an attempt to develop efficient load sharing mechanisms that improve the structure’s ability to resist vehicle impacts, while concurrently remaining aesthetically pleasing to the general public. A computational assessment was completed using calibrated LS-DYNA finite element models to determine if effective load sharing member configurations and designs could …
Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods,
2014
Portland State University
Wider Dissemination Of Household Travel Survey Data Using Geographical Perturbation Methods, Kelly J. Clifton, Steven R. Gehrke
Civil and Environmental Engineering Faculty Publications and Presentations
Public agencies spend vast amounts of money collecting information about passenger travel in household travel surveys. These data are valuable for the rich and detailed information they provide, which contribute to regional and statewide travel demand models. These data have utility beyond travel demand modeling in their application to transportation policy and travel behavior research. As the demand on these data increase, so have the quantity of information collected. Detailed geospatial referencing of the home, work and other travel destinations are common practice and permit the integration with other spatially archived data sources, such as land use characteristics, transportation system …
Responses Of Underground Structures Subjected To Blast Loading,
2014
CUNY City College
Responses Of Underground Structures Subjected To Blast Loading, Soufiane Nezilli
Dissertations and Theses
Terrorism against American citizens and assets is real and growing. The number and intensity of domestic and international terrorist events, along with the September 11, 2001, attacks, change the way Americans think and live. According to the Blue Ribbon Panel (BRP) on Bridge and Tunnel Security assigned by AASHTO, the US transportation system consists of 337 highway tunnels and 211 transit tunnels in 2003. The number is expected to grow in the near future. These tunnels are subjected to the threats of internal explosion, either accidental or maliciously intentional. Explosions inside transportation tunnels would result in direct casualties; and the …
Examining Optimal Form Of Two Scale Approximation (Tsa) For Calculating Snl Source Term,
2014
University of North Florida
Examining Optimal Form Of Two Scale Approximation (Tsa) For Calculating Snl Source Term, Dorukhan Ardag
UNF Graduate Theses and Dissertations
Nonlinear four-wave interactions (Snl) are critical for acquiring realistic spectra needed by operational wave models. High computational demand to calculate these interactions led to an approximation method named the Discrete Interaction Approximation (DIA) to be used broadly in the major operational wave models for a long time. However, the accuracy of the DIA has been controversial since it was first introduced and more precise approximations such as the Two Scale Approximation (TSA in short) are now available. The only issue with the initial TSA`s efficiency is performing an order of a magnitude slower than the DIA in speed. …
Evaluation Of The Empirical Deck Design For Vehicular Bridges,
2014
University of North Florida
Evaluation Of The Empirical Deck Design For Vehicular Bridges, Georges El-Gharib
UNF Graduate Theses and Dissertations
This research evaluated the feasibility of the empirical design method for reinforced concrete bridge decks for the Florida Department of Transportation [FDOT]. There are currently three methods used for deck design: empirical method, traditional method and finite element method. This research investigated and compared the steel reinforcement ratios and the stress developed in the reinforcing steel for the three different methods of deck design. This study included analysis of 15 bridge models that met the FDOT standards. The main beams were designed and load rated using commercial software to obtain live load deflections. The bridges were checked to verify that …
Factors Affecting Storm Characteristics In The Battery And Vicinity,
2014
University of North Florida
Factors Affecting Storm Characteristics In The Battery And Vicinity, Shannon A. Kay
UNF Graduate Theses and Dissertations
Tropical cyclones (TCs) Irene and Sandy caused major damages in back to back years to the most densely populated city in the United States stunning the residents with storms linked to seemingly impossible probabilities. Such activity has raised questions about the effect of non-stationary aspects within atmospheric circulation on storm behavior and some assumptions inherent in previous hazard studies of the New York City (NYC) area. This study analyzes statistical aspects of hazard quantification for this area related to this non-stationarity and statistical characterization. In particular this study investigates the presence of multiple populations of storms, it also tests current …
