Engineering Commons^™

Modeling Resilient Modulus Of Unbound Granular Materials Under Repeated Loading, Cheng Chen, Louis Ge, Jia Sheng Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Resilient modulus of unbound granular materials is a key design parameter for mechanistic empirical pavement design. But the complexity of the affected factors has made it challenging and difficult for practical designers and researchers to find an appropriate model to describe the entire stress-strain response where the plastic deformation is accumulated during the repeated loading condition. a cyclic plasticity model based on fuzzy sets plasticity theory is presented in this paper to model the resilient modulus and permanent strain behavior of unbound granular materials under repeated loading. the concept of the fuzzy set plasticity is first introduced, followed by its …

Ultrasonic Pulse Velocity Tests On Compacted Soil, David M. Weidinger, Louis Ge, Richard Wesley Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In This Paper, Results of a Series of Ultrasonic Pulse Velocity Tests on Compacted Soil Were Presented and Discussed. Ultrasonic Pulse Velocity Tests Provide Compression and Shear Wave Velocity Information that Can Be Used in Calculating Dynamic Elastic Moduli Such as Young's Modulus and Shear Modulus. from the Test Results, Calculated Poisson's Ratio Shows a Linear Relation with the Water Content in Compacted Soil, Which Leads to a Linear Trend in Both P and S Wave Velocity Against Water Content. Furthermore, Presenting Plots in Bulk Density Versus Wave Velocity Gives a Clearer Trend Than Dry Density Versus Wave Velocity. © …

Settlement Of Reinforced Subgrades Under Dynamic Loading, V. K. Puri, S. Kumar, B. M. Das, Shamsher Prakash, B. Yeo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Model tests were conducted in the laboratory to study the settlement behavior of small size footing resting on geogrid reinforced sand layer and subjected to dynamic loads. Tests were conducted by first subjecting the footing to an initial sustained static load and then superimposing additional predetermined dynamic loads. the frequency of dynamic load was kept at 1 Hz which was well below the resonant frequency of the system. based on the observed test results, the nature of variation of the permanent settlement of the foundation with intensity of static loading and the amplitude of cyclic load are presented in this …

Structural Damage Localization With Tolerance To Large Time Synchronization Errors In Wsns, Guirong Yan, Shirley J. Dyke, Wei Song, Gregory Hackmann, Chenyang Lu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

With Recent Technological Advances in Smart Sensor Platforms, Structural Condition Monitoring Implementations based on Wireless Sensor Networks (WSNs) Have Received Considerable Attention. Modal Identification is an Integral Step in Many Structural Condition Monitoring Systems. However, Accurate Time Synchronization is Not Always Possible, Leading to Incorrect Identification of the Mode Shapes. Although Strict Time Synchronization of the Wireless Sensors Has Been Viewed as Crucial for the Identification of Mode Shapes, a New Perspective is Taken Herein. the Distortion in the Identified Mode Shapes is Characterized and Accommodated. Then the Resulting Mode Shapes Are Used with a Flexibility-Based Damage Detection Approach to …

Use Of In-Planta Solid Phase Sampling Devices To Delineate Voc Plumes, Joel Gerard Burken, Kendra Waltermire, Emily Sheehan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Plants Directly Interact with Surrounding Water, Air, and Soil, Collecting and Storing Chemicals and Elements from the Surrounding Environment. Two New and Innovative Sampling Methods in Which This Valuable Data Can Be Accessed to Replace as Well as Supplement Contaminated-Site Investigations Have Been Developed. When Determining the Extent of the Plume on a Contaminated Site, Groundwater Sampling May Be Limited Due to Time, Site Access, and Expense. by using New Techniques that Place Sampling Devices Inside the Trees on Site, We Can Sample Trees Naturally Occurring on a Contaminated Site or Those Planted in Phytoremediation or Redevelopment Efforts, Evaluate the …

Model For Reinforced Concrete Members Under Torsion, Bending, And Shear. I: Theory, Gary Greene, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A model has been developed that can predict the load-deformation response of a reinforced concrete (RC) member subjected to torsion combined with bending and shear to spalling or ultimate capacity. the model can also be used to create interaction surfaces to predict the failure of a member subjected to different ratios of applied torsion, bending, and shear. the model idealizes the sides of a reinforced concrete member as shear "wall panels." the applied loads are distributed to the wall panels as uniform normal stresses and uniform shear stresses. the shear stress due to an applied torsional moment and shear force …

Model For Reinforced Concrete Members Under Torsion, Bending, And Shear. Ii: Model Application And Validation, Gary Greene, Abdeldjelil Belarbi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A model was recently proposed for predicting the load-deformation response of a reinforced concrete member under torsion combined with bending and shear to spalling or ultimate. This paper shows the application of the model to create interaction surfaces to predict the failure of a member subjected to different ratios of applied torsion, bending, and shear. the model was validated by comparing the predicted and experimental behavior of 28 members from three experimental studies available in the literature. the members were loaded under torsion combined with different ratios of bending, and shear. the torque-twist behavior, reinforcement stress, and concrete surface strain …

Lignin And Lipid Impact On Sorption And Diffusion Of Trichloroethylene In Tree Branches For Determining Contaminant Fate During Plant Sampling And Phytoremediation, Gayathri Gopalakrishnan, Joel Gerard Burken, Charles J. Werth

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Plants Draw All They Need from their Surrounding Environment and in Doing So Also Draw Anthropogenic Contaminants from their Surroundings. Several Natural Processes (E.g., Active Transport, Diffusion, Sorption, and Degradation) Occur within Trees and Affect Chemical Concentrations in Tree Samples. This Study Elucidates Tree Contaminant Chemical Interactions on Equilibrium Sorption and Diffusion into Branch Tissue (I.e., Wood Core and Bark), Specifically the Impacts of Lipid and Lignin Content. Five Tree Species Were Selected to Span a Range of Lignin and Lipid Contents. Linear Isotherms Were Obtained for All Sampled Species over a Limited Concentration Range (2 Μg/ ML < C Gas < 12 Μg/mL), and Equilibrium Distribution Coefficients (Kd) Were Linearly Correlated to Lipid (R2 > 0.83) But …

The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern

Other resources

This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …

Conference Review - 4th International Phytotechnologies Conference, Denver, Co, September 24-26, 2007, Jason C. White, Joel G. (Gerard) Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu

Conference Papers

Research studies have shown that the initial energy embodied in a building can be as much as 67% of the operational energy over a 25 year period. With growing global concerns over material and resource consumption and the emissions of CO2 into the atmosphere, the energy embodied in buildings constructed in town and cities becomes important and one of the key issues that needs to be tackled in the design stages in order to strive towards sustainable buildings design. In this paper, a hybrid embodied carbon dioxide equivalent (CO2eq) methodology used to assess the CO2eq embodied in buildings is presented. …

Land Conservation And Land Use In New England: Trends, Challenges & Opportunities, Amanda Loomis, Tom Devine, Andrea Small, Brittany Howard, Brett Richardson, Stephanie Dulac

Land Conservation

Sprawling development patterns accelerated across the New England landscape in the last three decades and consumed the region‘s forests, farms, and open spaces at an unprecedented rate. New England‘ers in all six states formed land trusts, supported statewide conservation organizations, and collaborated with state and federal partners to protect some of their most-prized recreation lands, wildlife habitats, and working lands. The current economic recession has slowed development pressures across the region and offers an opportunity to build on recent successes. The time is right to plan a coordinated New England conservation strategy that protects and links the region‘s natural assets. …

Why Is Fresh Self-Compacting Concrete Shear Thickening?, Dimitri Feys, Ronny Verhoeven, Geert De Schutter

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Rheological Properties of Fresh Concrete Are Mostly Described by Means of the Bingham Model. for Self-Compacting Concrete, the Bingham Model is Applicable in a Lot of Cases, But Some Authors Report that the Rheological Behavior is Non-Linear. the Apparent Viscosity Increases with Increasing Shear Rate and the SCC Shows Shear Thickening Behavior. Shear Thickening Becomes Important in Operations Occurring at High Shear Rates, Like Mixing and Pumping. in These Cases, Shear Thickening Should Not Be Forgotten in Order to Avoid Breaking of the Mixer, Pump or Pipes. This Paper Will Describe Two Possible Theories for Shear Thickening Behavior of …

South Burlington Vt: New Urbanist South Village, Jack Kartez, Richard Barringer

Planning

The 220 acre master plan for South Village, the largest project in the City of South Burlington’s history, encompasses multiple housing types and innovative provisions for affordable housing. It integrates housing with open space and natural resource conservation, including a major Community Supported Agriculture project developed by a nonprofit partner, the Intervale Foundation. While not a mixed-use project (that is, commercial as well as residential development), South Village nonetheless represents a qualitative change in approach for South Burlington by incorporating large-scale open space preservation as part of development and multiple housing-types in one project. The case study recounts events leading …

Interview With Kirk Davis, Glumac International, 2009 (Audio), Kirk Davis

All Sustainability History Project Oral Histories

Interview of Kirk Davis by Jay Fielding at Glumac International, Portland, Oregon on May 22nd, 2009.

The interview index is available for download.

Sustainable Portland: Implementation Series 2, New England Environmental Finance Center

Climate Change

The Portland Municipal Climate Change Working Group prepared a report in March 2008 that outlined several recommendations as a commitment by the City to address greenhouse gas emissions (GHG) produced during daily municipal operations. The Municipal Climate Action Plan was written in partnership with Clean Air – Cool Planet and Portland officials, and acknowledges under Recommendation #2 that an employee energy efficiency program would provide significant positive impact on the City’s reduction of greenhouse gas emissions. Best practices from three cities show that focus on the greening of City Hall is critical in developing a program that promotes partnerships, community …

Integration Approach Of The Couette Inverse Problem Of Powder Type Self-Compacting Concrete In A Wide-Gap Concentric Cylinder Rheometer. Part Ii. Influence Of Mineral Additions And Chemical Admixtures On The Shear Thickening Flow Behaviour, G. Heirman, R. Hendrickx, L. Vandewalle, D. Van Gemert, D. (Dimitri) Feys, G. De Schutter, B. Desmet, J. Vantomme

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Influence of Mineral Additions and Chemical Admixtures on the Shear Thickening Flow Behavior of Powder Type Self-Compacting Concrete (SCC) is Studied by Means of a Wide-Gap Concentric Cylinder Rheometer. the Couette Inverse Problem is Treated by Means of the Integration Method in Order to Derive the Flow Curve Τ(Γ̇) from the Torque Measurements. According to the Experimental Results, the Shear Thickening Effect is Found to Be Strongly Influenced by the Addition of the Chemical Admixture (A Polycarboxylate Ether based Superplasticizer), Whereas Mineral Additions Were Found to Modify the Intensity of Shear Thickening. the Limestone, Quartzite and Fly Ash Addition …

Preserving Assets In At-Risk Municipalities: Financial Strategies For Climate Change Adaptation, New England Environmental Finance Center

Climate Change

A large share of America's population, businesses and economic activity now occurs in coastal areas. At the same time, during this century many coastal communities are likely to be severely impacted by sea level rise and increased storm surge and tidal flooding.

“What to do” about this vulnerability is the subject of this brief. It is intended to help municipalities identify courses of action and steps they might take toward increasing their resilience, especially regarding financial resources that will need to be allocated toward the various strategies identified.

Taproot™ Technology: Tree Coring For Fast, Noninvasive Plume Delineations, Joel Gerard Burken, Sallie Bailey, Matt Shurtliff, Jeff Mcdermott

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In Efforts to Evaluate the Use of Plants as a Forensic Tool for Delineating Contaminated Soil and Groundwater, a Laboratory Experiment and a Field Sampling Effort Were Undertaken. Site Assessments Are Often Costly and Inaccurate, Requiring Multiple Mobilizations to Hone in on Source Areas and Getting Accurate Estimates of Contaminant Extent and Distribution. as These Extensive Site Delineations Take Place, Valuable Time and Resources Are Lost. the Findings of This Study Show that Plants Can Be Used as a Tool to Evaluate a Variety of Subsurface Contaminants, Either in the Vadose Zone or in the Saturated Zone. in the First …

Predicting The Perforation Response Of Honeycomb Sandwich Panels Using Ballistic Limit Equations, William P. Schonberg, Frank Schäfer, Robin Putzar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Man-made debris from previous spacecraft missions poses a serious threat to spacecraft that are launched to operate in Earth orbit because it can strike such spacecraft at extremely high velocities and consequently damage mission-critical systems. Most satellites are constructed with honeycomb sandwich panels as their primary structural elements. to be able to perform a risk analysis, it is important to know, in the event of such a meteoroid or orbital debris particle impact, whether or not the impacting particle or parts thereof will exit the rear of the sandwich panel. a recently developed set of ballistic limit equations for two …

Risk Indexes For Draft Ccl3 Chemicals, J. Alan Roberson, Matthew Lueders, Craig Adams, Jeffrey S. Rosen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

To supplement the processes used for developing the draft third Contaminant Candidate List (CCL3) and better inform decisions made by the US Environmental Protection Agency on future CCLs, the authors offer an evaluation tool for efficiently synthesizing, visualizing, and organizing data for effective comparisons among contaminants. Graphical presentations of health effects-occurrence indexes were developed for more than 300 chemical contaminants, including those on the draft CCL3. a risk indexes framework was then used to elucidate the extent of available data, the data quality, and the underlying uncertainties for occurrence and toxicity. Choosing the appropriate contaminant for regulation is a complex …

Managing Risks Associated With The Jbcc(Principal Building Agreement) From Thesouth African Contractor’S Perspective, Ayman Ahmed Ezzat Othman, Nishani Harinarain

Architectural Engineering

Construction is a complex and risky business. It is a time-consuming process involving a multitude of organisations with different objectives and skills. In addition, increasing client expectations coupled with the technological development of materials and equipment made the construction industry subject to more risks than any other industry. Contracts are essential tools for organising the relationship between involved parties and managing associated risk. For years the South African construction industry had a very poor reputation in managing construction risks. In order to improve the image of the South African construction industry and to assist contractors to develop their proper risk …

Damage Characterization Of Beam-Column Joints Reinforced With Gfrp Under Reversed Cyclic Loading, Aly M. Said

Civil and Environmental Engineering and Construction Faculty Research

The use of fiber reinforced polymer (FRP) reinforcement in concrete structures has been on the rise due to its advantages over conventional steel reinforcement such as corrosion. Reinforcing steel corrosion has been the primary cause of deterioration of reinforced concrete (RC) structures, resulting in tremendous annual repair costs. One application of FRP reinforcement to be further explored is its use in RC frames. Nonetheless, due to FRP's inherently elastic behavior, FRP-reinforced (FRP-RC) members exhibit low ductility and energy dissipation as well as different damage mechanisms. Furthermore, current design standards for FRP-RC structures do not address seismic design in which the …

Heat Transfer Correlations For Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

The experimental performance of an open industrial scale cooling tower, utilising small approach temperature differences (1–3 K), for rejection of heat at the low water temperatures (11–20 °C) typical of chilled ceilings and other sensible air–water heat dissipation systems in buildings, is examined. The study was carried out under temperate maritime climatic conditions (3–18 °C wet-bulb temperature range). Initially a theoretical analysis of the process at typical conditions for this climate was conducted, which indicated that a water to air (L/G) mass flow rate ratio of less than 1.0 was required for effective operation. Consequently for these low L/G ratios, …