Civil Engineering Commons^™

A Better Way To Build Plant Models, Dean Holzworth, Hamish Brown, Neil Huth

International Congress on Environmental Modelling and Software

The plant modelling framework (PMF) in the next generation of APSIM enables plant models to be constructed in a novel, more reliable and robust manner. It provides a library of small processes that can be aggregated into bigger processes which in turn can be combined into larger constructs, ultimately forming a plant model. The user interface supports a workflow that allows the model builder to collate and store experimental data, construct the model (by process aggregation), create and run simulations of the experimental data and graphically view the performance of the model. The model builder can then iteratively modify the …

Towards Standard Variable Names For Environmental Chemistry: Semantic Mediation And Extensions To The Csdms Standard Names, Scott Dale Peckham

International Congress on Environmental Modelling and Software

When a model needs to obtain the values of its input variables from another model or from a data file, it is necessary to reliably match the internal vocabularies of the coupled resources (e.g. models or data sets). In addition, spatial regridding, time interpolation and unit conversion may be required. In order to automate this semantic matching and variable exchange process in a model coupling framework, the internal vocabularies of the resources to be coupled must be mapped to a controlled vocabulary in a hub-and-spoke manner. The CSDMS Standard Names provide a domain-independent set of conventions and rules for constructing …

How Modellers Frame Uncertainty In Scientific Publications: Review And Reflections, Joseph H.A. Guillaume, Casey Helgeson, Sondoss Elsawah, Anthony J. Jakeman, Matti Kummu

International Congress on Environmental Modelling and Software

Uncertainty is recognised as an essential issue in environmental modelling. As modellers, we notably use a variety of tools and techniques within an analysis, for example related to uncertainty quantification and model validation. We also address uncertainty by how we present results. For example, experienced modellers are careful to distinguish robust conclusions from those that need further work, and the precision of quantitative results is tailored to their accuracy. In doing so, the modeller frames how uncertainty should be interpreted by their audience. This is an area which extends beyond modelling to fields such as philosophy of science, semantics, discourse …

Modelling Combinations Of Economic Instruments To Eliminate Depletion In The Alto Guadalentín Aquifer (Se Spain), David Martínez-Granados, Javier Calatrava

International Congress on Environmental Modelling and Software

This paper analyses the cost-effectiveness of combining several policy instruments to address the problem of non-renewable pumping in the Alto Guadalentín aquifer in Southeast Spain, one of the most extreme cases of aquifer depletion in Europe. Their economic impact is assessed using a partial equilibrium non-linear mathematical programming model that maximises the farm net margin resulting from the use of the available water resources for irrigation in the area. Our results show that all the alternatives have significant economic impacts, although the future availability of desalinised resources would notably mitigate them, as farmers can substitute groundwater with desalinised water. …

Lifelong Housing Design: User Feedback Evaluation Of Smart Objects And Accessible Houses For Healthy Ageing, Matteo Zallio, Niccolò Casiddu

Conference Papers

According to the latest research by the European Community and ISTAT (Italian National Institute of Statistics) surveys, Europe has the highest average age for its population. According to those data, in the near future, it could be necessary to move from a welfare model based on the centralization of care systems, to a system based on the distribution of certain healthcare facilities [1]. This means that the ageing population is ever increasing, thanks to better lifestyles, innovative medical care and wider access to different services. This work seeks to observe and analyse key implications of architectural and interior design features …

Experimental And Numerical Evaluation Of A New Composite Pressure Pipe For A Trenchless Rehabilitation Technology, Xuanchen Yen

Doctoral Dissertations

The information presented in this dissertation is based on research work conducted at Trenchless Technology Center (TTC) at Louisiana Tech University. This work was performed through a contract with China University of Geoscience (CUG) for a gas company. China's gas pipelines need replacement or rehabilitation after 15 to 30 years of service. China's gas industry is looking for suitable techniques to transfer into their market.

When compared to conventional excavation pipeline renewal or replacement methods, there are obvious advantages of TRT for gas pipelines that can impact the triple bottom-line of economic, social and environmental benefits. An introduction of TRT …

The Experiment And Analysis Of Active Mechanisms For Enhancing Heat And Mass Transfer In Sorption Fluids, Ziqi Shen

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This project was funded by American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE RP-1462). It is a three years’ research, including the literature review, labs construction, experiments and data analysis.

In this thesis, first of all, we conducted literature review of mechanism motion influence on heat and mass transfer and additive effect in absorption chiller. This part helps us understand the basic idea of how mechanism motion affects the heat and mass transfer of sorption fluids and gives us reference on how to select the experiment instrument and the experiment operation range.

In the second part, the instrument selection …

Correlating Interlaminar Fatigue Fracture Behavior To Nde Parameters In Carbon/Epoxy Composites Containing Voids And Delamination, Issa Hakim, Norbert Meyendorf, Steven L. Donaldson, René Laquai, David Walter, Bernd Müller, Paul Graja

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Carbon fiber composites have been increasingly used in aerospace, military, sports, automotive and other fields due to their excellent properties, including high specific strength, high specific modulus, corrosion resistance, fatigue resistance, and low thermal expansion coefficient. Delamination, or interlaminar fracture, is a serious failure mode leading to a loss in composite stiffness and strength. Manufacturing process defects such as voids degrade the fatigue life and delamination resistance of the composite. This study investigates the effect of voids on fatigue interlaminar fracture behavior of carbon fiber composites. Samples with different vacuum levels: 0%, 50% and 100% were fabricated by varying the …

Global Sensitivity Analysis Of Mat Foundation Behavior By Using Finite Element Modeling, Yang Zhao

Civil & Environmental Engineering Theses & Dissertations

Mat foundation is used mostly for high-rise buildings and, since the demand for high- rise buildings is growing, having extensive understanding of mat foundation behavior leads us into more efficient structural design. Mat foundation behaviors are affected mostly by soil’s materials properties, foundation size, and thickness and loading conditions. In this study, the sensitivity of mat foundation structural responses to some of the design parameters are evaluated. Sobol decomposition, which is a variance-based technique, is used to perform the global sensitivity analysis. In this study, Patran, a finite element-based software, is used for modeling and simulations.

Approximate flexible method is …

Bs News July/August

Building Services Engineering

No abstract provided.

A Tool For Downscaling Weather Data From Large-Grid Reanalysis Products To Finer Spatial Scales For Distributed Hydrological Applications, Avirup Sen Gupta, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

A downscaling tool was developed to provide sub-daily high spatial resolution surfaces of weather variables for distributed hydrologic modeling from NASA Modern Era Retrospective-Analysis for Research and Applications reanalysis products. The tool uses spatial interpolation and physically based relationships between the weather variables and elevation to provide inputs at the scale of a gridded hydrologic model, typically smaller (∼100 m) than the scale of weather reanalysis data (∼20–200 km). Nash-Sutcliffe efficiency (NSE) measures greater than 0.70 were obtained for direct tests of downscaled daily temperature and monthly precipitation at 173 SNOTEL sites. In an integrated test driving the Utah Energy …

Cfd Study Of Decay Function Of Wall Shear Stress With Scour Around Complex-Shape Bridge Pier, Chen Li

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Pier scour problem is close related to the safety of bridges. The Federal Highway Administration of the United State also has a great interest in studying the relation between hydraulic loadings and scour depth. The current technological problem of directly measuring hydraulic loadings on a dynamic bed using physical experiments and the weak capacity to simulate the real scour processes with CFD methods inspired the development of a hybrid approach by combining them to study pier scour.

This research specifically focuses on the CFD part of the hybrid method. A series of three-dimensional (3-D) CFD models were developed with unsteady …

Automated Device To Measure Slurry Properties In Drilled Shafts, Miles Patrick Mullins

USF Tampa Graduate Theses and Dissertations

Slurry is the fluid within a drilled excavation that is introduced when an excavation is deeper than the water table or where additional stability is needed for loose sandy dry soils. Although construction practices vary greatly throughout the country and the world, slurry levels should be maintained above the existing ground water level by a suitable margin. The most widely used slurry type is mineral slurry formed by mixing dry clay powder with water; either bentonite or attapulgite powder may be used (attapulgite being used in saline water conditions). Regardless of whether the slurry material is mineral, polymer or natural, …

Modeling Human-Structure Interaction Using A Controller System, Albert Ricardo Ortiz Lasprilla

Theses and Dissertations

The effects of human loads on structures are difficult to predict because they depend on the type of activity people are performing. However, models for typical activities such as standing, sitting and jumping have been proposed in the literature. Traditional models represent the human body as a system of lumped masses, dampers and springs arranged in a system with multiple degrees of freedom. Arguably, these models might not fully represent the human body because lumped masses, dampers and springs cannot add energy to the overall system. Furthermore, people could react differently to different levels of excitation and other environmental conditions. …

Multiscale Modeling Of Water Transport And The Influence Of Water Quality Parameters On Membrane Processes, Linkel Kwabena Boateng

Theses and Dissertations

Membrane-based desalination processes have become a viable means of producing potable water to meet water resource needs in both industrialized and developing nations. Extensive experimental investigation, in conjunction with computational modeling is critical in the development of sustainable and cost-effective desalination technologies. The overall goal of this dissertation is to develop a multiscale modeling framework to elucidate water and salt transport mechanisms and the influence of water quality parameters on membrane processes. The key tasks involved in this study are: establish a criterion for estimating water flux using Bayesian inference; develop a multiscale framework to connect molecular dynamics (MD) simulations …

Evaluation Of Spillway Stilling Basin Performance And Reservoir Sediment Flushing In A Physical Model Case Study: Due Hydroelectric Project In Ecuador, Ali Habibzadeh, Brian Hughes, Hernan Barahona

International Symposium on Hydraulic Structures

The Due Hydroelectric Project is a proposed 50 MW run-of-river hydroelectric project being developed by Hidroalto SA. The project will be located on the Rio Due in Ecuador. The civil works of the intake facility will be comprised of a 133.45 m wide diversion weir, with two overflow spillways and six gated sluice channels; a four bay intake structure with sediment excluder; and, a fish bypass facility. Northwest Hydraulic Consultants (NHC) evaluated the initial design of the Due intake and spillway facilities using a 1:35 Froude-scaled physical model for river discharges ranging from the intake design discharge of 57.2 m3 …

Decision-Making Through Sustainability, F. Pardo-Bosch, A. Aguado

International Symposium on Hydraulic Structures

From immemorial time, dams have contributed significantly for the progress of civilizations. For this reason, nowadays, there is a vast engineering heritage. Over the years, these infrastructures can present some ordinary maintenance issues associated with their normal operation or with ageing processes.

Normally, these problems do not represent an important risk for the structure, but they have to be attended. To do it, owners of dams have to finance many ordinary interventions. As it is impossible to carry out all of them at the same time, managers have to make a decision and select the most “important” ones. However, it …

Computational Code For Optimization Of Thermal Treatment Of Fine Grained Soils As A Method Of Expediting Their Load Induced Consolidation, Radhavi Abeysiridara Samarakoon

USF Tampa Graduate Theses and Dissertations

Construction in soft soils has been a challenging task for engineers due to the excessive time taken for dissipation of construction induced pore water pressure and the ensuing postconstruction settlement. Use of vertical drains has proven to be an effective and economical method for soft ground improvement and hence extensive research has been carried out to further improve its efficiency. Effect of temperature on radial consolidation is one aspect of such research among many others that have been pursued.

Elevated temperature certainly has a pronounced effect on the hydraulic conductivity due to the reduction it causes in the viscosity of …

Development Of An Instrument To Measure The Entrepreneurial Mindset Of Engineering Students, Cheryl Q. Li, Ronald S. Harichandran, Maria-Isabel Carnasciali, Nadiye O. Erdil, Jean Nocito-Gobel

Civil Engineering Faculty Publications

This work in progress describes the development of an instrument to measure entrepreneurial mindset of engineering students. The need for developing the entrepreneurial mindset of engineering students is being recognized by many universities. However, very few comprehensive, generalized and well-validated instruments are available for assessing the entrepreneurial mindset of engineering students. Most research and educational efforts focus on the design and implementation of engineering entrepreneurship programs, but assessment practices have not kept up.1-2 There are several reasons for the shortfall in assessment practices: 1) Introducing engineering students to entrepreneurship is a relatively new trend and it will take time for …

Why This Flip Wasn't A Flop: What The Numbers Don't Tell You About Flipped Classes, Heather Noel Fedesco, Troy Cary

IMPACT Publications

This paper details the conversion of a large, required Civil Engineering fluid mechanics course into a more student-centered, active learning-oriented course through the flipping of one lecture per week. In the flipped class, students collaboratively solve homework problems in groups while receiving “expert” feedback from instructors and TAs. To offset the lost lectures, some course material that has been delivered in traditional lectures has been placed online in the form of short videos and textbook readings, with low-stakes quizzes for assessment.

Student learning gains were quantitatively assessed by comparing quiz and final exam scores for three semesters (1 pre-flip and …