Civil Engineering Commons^™

Optimal Design Of Grillage Structures With Steel Crossed Beams Using Genetic Algorithms, Ersilio Tushaj, Niko Lako, Fatjon Saliu

UBT International Conference

The optimal problem in the structural design is an important issue in the engineering design. Various authors have analyzed the optimization of steel structures using algorithmic approaches. These techniques are generally grouped in deterministic or meta-heuristic techniques. From the introduction of structural optimization in the 1960’ up to now, various methods have been proposed. A genetic algorithm, is built and applied in this study using MatLab soft R2017a to a crossed beams system. The structural analysis is done with the direct stiffness method with constraints verification based on EuroCode 3:2005 criteria. Results are reported in the study.

Beam- Column Joints For R/C Structures According To En 1998-1:2004, Xhemshir Mulliqi

UBT International Conference

Joints are crucial zones for the transfer internal forces effectively between the connecting elements like beams and columns .The behaviour of reinforced concrete moment resisting frame structures in recent earthquakes all over the world has highlighted the consequences of poor performance of beam column joints. The basic requirement of design is that the joint must be stronger than the adjoining hinging members, usually the beams or columns. This paper aims to present design approach for Beam- Column joints for reinforced concrete (R/C) structures according to the EN 1998-1:2004.

The Effect Of Elevated Temperature On The Lightweight Concrete Containing Waste Pet Aggregate, Semiha Akçaözoğlu

UBT International Conference

In this study, the effect of waste PET as lightweight aggregate (WPLA) replacement with conventional aggregate on the some physical and mechanical properties and residual compressive strength of concrete was investigated. For this purpose, five different mixtures were prepared (the reference mixture and four WPLA mixtures including 30%, 40%, 50% and 60% waste PET aggregate by volume). The fresh and dry unit weights, compressive strengths, flexural-tensile strengths, water absorption and porosity ratios of the mixtures were measured. In addition the specimens exposed to elevated temperatures at 150, 300 and 450 °C and the residual compressive strengths were measured. Test results …

The Effect Of Fine Material Amount On Optimum Water Content Of Roller Compacted Concrete, Kubilay Akçaözoğlu, Bedrettin Menemencioğlu

UBT International Conference

In this study the effect of fine material amount on the optimum water content of roller compacted concrete (RCC) was investigated. The fine aggregate was replaced with calcite which maximum particle size was 63 μ, in amount of 0%, 2%, 4%, 6%, 10% and 14% by weight of total aggregate. Six different mixtures were prepared in the study. The optimum water contents of the mixtures were determined by using modified proctor test. Optimum water content, maximum dry unit weight and maximum fresh unit weight of produced specimens were measured. Optimum water content of specimens decreased depending on increasing fine aggregate …

Sustainability Of Community-Managed Rural Water Supply Systems In Amazonas, Peru: Assessing Monitoring Tools And External Support Provision, Jacob E. Mangum

USF Tampa Graduate Theses and Dissertations

Globally, there is still a large number of people without access to safe drinking water; a known health risk. In rural areas of countries like Peru, when potable water systems are built the responsibility for maintaining these systems is given to volunteer water committees. Despite its prevalence as a management model, there is a consensus that community management alone cannot ensure sustainable water service. Therefore, the overall goal of this research is to assess the sustainability of community-managed water systems in rural areas of the department of Amazonas, Peru. Specifically, this research examines two mechanisms that have been shown to …

Safety Effectiveness Of Pedestrian Crossing Treatments, Christopher Monsere

PSU Transportation Seminars

Over the last decade, the transportation agencies in Oregon have systematically enhanced many pedestrian crossings at mid-block locations with Rectangular Rapid Flashing Beacons (RRFBs), Flashing Yellow Beacons (Flash), and high visibility crosswalk markings (Hi-Vis). Enhancements often included the installation of refuge medians. This study explored the safety performance of these enhanced crossings, categorized by enhancement type. Data were collected on 191 crossings that included installation year, geometric features, surrounding land use, traffic volumes, and the number of crashes. Because pedestrian volume at the locations was unavailable, a pedestrian activity level variable was developed. Target crashes for analysis were identified as …

Performance Evaluation Of Rice Husk Ash (Rha) Modified Concrete, Mohammad Badrul Ahsan

Student Theses and Dissertations

Rice husk ash (RHA) is an agricultural by-product that has the potential of a pozzolanic material. It can be used as a partial replacement of Ordinary Portland Cement (OPC) in concrete. The present study investigates the performance of RHA-modified concrete with two amounts (10% and 20% by weight) of three types of RHA. Test results of RHA-modified concrete samples have been compared with those of the Control (no RHA) as well as concrete modified with a commonly used modifier called Class C fly ash (CFA) with 10% replacement. Effects of alkali-silica reaction (ASR) and deicing chemicals have also been evaluated …

Datumate, Purdue Ect Team

ECT Fact Sheets Archive

Datumate is digitally transforming civil engineering processes used in construction, surveying and infrastructure inspection markets with fully automated, highly precise, cost effective and safe tools. It utilizes state-of-the-art image processing and advanced drones and camera technologies dramatically reducing the amount of time surveying crews spend in the field, speeding up construction progress checks and shortening infrastructure inspection duration, while maintaining survey grade accuracy. The intuitive, simple and automated solutions increase productivity by saving field and office time in civil engineering and inspection projects of roads, intersections, stockpile volumes, topography, piping, industrial facilities, bridges, property surveys, building facades, railways, cellular infrastructure …

Erosion Behavior And Scour Risk Of Extremely Coarse Streambeds, Abolfazl Bayat

Dissertations

Bridge scour, which is the erosion of soil and rock around bridge abutments and piers, is the principal cause of bridge failure in the United States and around the world. Previous investigations of scour have focused mostly on fine sediments such as sand, silt, and small gravel, because such alluvium underlies a majority of bridges. The erosion resistance of coarser sediments has received limited attention to date, even though they dominate many small to medium-size rivers in the northern tiers of the United States, Europe, and Asia. This study focuses on the scour behavior of extremely coarse particles (ECP), namely …

A Comparative Study On The Durability Of Geopolymer Mortars Produced With Ground Glass Fiber, Fly Ash, And Glass-Powder In Sodium Sulfate Solution, Hassan Rashidian-Dezfouli, Prasada Rao Rangaraju

Publications

An experimental investigation was conducted to investigate the performance of geopolymers made with three different precursors consisting of fly ash, Ground Glass Fiber (GGF), and Glass-Powder (GLP) exposed to sodium sulfate solution. Precursors were activated using either sodium hydroxide solution or combinations of sodium hydroxide and sodium silicate solution with varying levels of sodium and silica content. Among the mixtures with each of the three precursors, mortar mixtures with the highest compressive strength were selected to test their resistance against exposure to a 5% sodium sulfate solution. Changes in the weight and compressive strength of the specimens were monitored up …

Geopolitical Relations: Uganda’S Role In The Development Of The River Nile, Jordan Williams

Independent Study Project (ISP) Collection

This study examined the geopolitical relations of the Nile Basin by looking at Uganda as a case study, and analyzed Uganda’s use and development of the River Nile. It reviews the history of transboundary politics and treaties along with Uganda’s development projects in the region. The paper then discusses modern relations and agreements, with a focus on the most recent agreement between the Riparian States, the Cooperative Framework Agreement, and how Uganda fits into them with regards to their interest in hydropower development within their borders on the Nile. It then explores possible future developments on the river and the …

Reliability Analysis Of Active Earth Pressure For Cantilever Walls On Mudflows And Residual Soils Of The Aburrá Valley, Juan David Castro, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

According to the variability of the local geology of the Aburrá Valley, two geological strata with similar grain size distribution were analyzed. The geologies are composed of mudflows and residual soils from the San Diego stock in the Poblado neighborhood. These soils show a similar mechanical behavior in relation to the number of blows of the standard penetration test SPT. The analysis was carried out by reliability methods for the determination of the active earth pressure for the geotechnical design of a cantilever walls. The analysis consists in the variation of the height of the retaining wall between 1 and …

Reliability Analysis Of Geosynthetic Reinforced Soil Walls, Michael Powers

Graduate Theses & Non-Theses

Geosynthetic reinforced soil walls have been widely used for earth retention and stabilization in many geotechnical applications. In the traditional design of geosynthetic reinforced soil walls, Allowable Stress Design (ASD) is used to address the uncertainties. However, it cannot explicitly consider the uncertainties in a systematic way in the design process; especially geotechnical uncertainties are typically at high levels and problem-specific. Traditional methods usually result in over-conservativeness, inconsistence, and empiricism in the design practice. Recently there has been a trend of the application of reliability methods for design of geosynthetic reinforced soil walls to explicitly address uncertainties in the design …

Performance-Based Contracting For Rest Area Maintenance, Michael Powers

Graduate Theses & Non-Theses

To maintain rest area stops in the United States, three methods are used. They are the In-House method, Method-Based Contracting (MBC), and Performance-Based Contracting (PBC). In recent years, the PBC method has become increasingly popular because this method reduces the strain of managing In-House employees or MBC contracts, generates more business in the public sector, can increase the level of service (LOS), and generally reduces the costs of maintaining rest area stops up to 5%. In the United States, no less than 15 states use the PBC method to maintain their rest area stops, and the results from switching to …

Geology Influence In The Slope Stability Analysis By Limit Equilibrium, Finite Elements And Random Finite Elements Methods, Juan Camilo Viviescas, Juan Pablo Osorio

Conference papers

Slope stability analyzes correspond to the evaluation of the safety factors commonly performed through the limit equilibrium and finite element methods. Due to the uncertainty of the geotechnical parameters, different statistical methods have emerged such as the limit equilibrium combined with the Monte Carlo simulation method and the random finite elements, which have been widely accepted in recent years. Normally, these analyzes are not performed taking into account the geological influence on the geotechnical properties, so in this work we proceed with the comparison of several geometrical typologies of slopes for mudflows and a residual soils of the Stock San …

Chemical Variations And Engineering Implications Of Reclaimed Asphalt Pavement And Chemically Modified Asphalt Binders, Md Shahriar Al Alam

Student Theses and Dissertations

Petroleum crude oil, the prime source of asphalt binder, originates from many naturally occurring crude sources, which vary widely in chemical compositions. These compositions are defined as Saturates, Aromatics, Resins, and Asphaltenes (SARA) fractions. Physical properties of an asphalt binder are closely linked to its crude-inherited SARA fractions. Thus, asphalt binders differ significantly from one another, while they are intended to serve the same way under a specified traffic loading intensity and temperature. To serve this need, asphalt binders are often modified chemically. Sometimes, Reclaimed Asphalt Pavement (RAP) is added to this binder because of the limited supply of virgin …

Climate, Not Conflict, Explains Extreme Middle East Dust Storm, Anthony J. Parolari, Dan Li, Elie Bou-Zeid, Gabriel Katul, Shmuel Assouline

Civil and Environmental Engineering Faculty Research and Publications

The recent dust storm in the Middle East (September 2015) was publicized in the media as a sign of an impending ‘Dust Bowl.’ Its severity, demonstrated by extreme aerosol optical depth in the atmosphere in the 99th percentile compared to historical data, was attributed to the ongoing regional conflict. However, surface meteorological and remote sensing data, as well as regional climate model simulations, support an alternative hypothesis: the historically unprecedented aridity played a more prominent role, as evidenced by unusual climatic and meteorological conditions prior to and during the storm. Remotely sensed normalized difference vegetation index demonstrates that vegetation cover …

Hydrologic Transport Of Dissolved Inorganic Carbon And Its Control On Chemical Weathering, Salvatore Calabrese, Anthony J. Parolari, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Chemical weathering is one of the major processes interacting with climate and tectonics to form clays, supply nutrients to soil microorganisms and plants, and sequester atmospheric CO₂. Hydrology and dissolution kinetics have been emphasized as factors controlling chemical weathering rates. However, the interaction between hydrology and transport of dissolved inorganic carbon (DIC) in controlling weathering has received less attention. In this paper, we present an analytical model that couples subsurface water and chemical molar balance equations to analyze the roles of hydrology and DIC transport on chemical weathering. The balance equations form a dynamical system that fully determines …

A Comparative Life Cycle Assessment Between A Metered Dose Inhaler And Electric Nebulizer, Brandon Goulet, Lars E. Olson, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Life cycle assessment (LCA) evaluates the environmental impact of a product based on the materials and processes used to manufacture the item as well as the item’s use and disposal. The objective of this LCA was to evaluate and compare the environmental impact of a metered dose inhaler, specifically the Proventil® HFA inhaler (Merk & Co., Inc., Kenilworth, NJ, USA), and an electric nebulizer, specifically the DeVilbiss Pulmo-Aide® nebulizer (DeVilbiss, Port Washington, NY, USA). GaBi LCA software was used to model the global warming potential (GWP) of each product by using substantiated data and well-justified assumptions for the components, manufacturing, …

Boom And Bust Carbon-Nitrogen Dynamics During Reforestation, Anthony J. Parolari, Megan L. Mobley, Allan R. Bacon, Gabriel Katul, Daniel Deb. Richter, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Legacies of historical land use strongly shape contemporary ecosystem dynamics. In old-field secondary forests, tree growth embodies a legacy of soil changes affected by previous cultivation. Three patterns of biomass accumulation during reforestation have been hypothesized previously, including monotonic to steady state, non-monotonic with a single peak then decay to steady state, and multiple oscillations around the steady state. In this paper, the conditions leading to the emergence of these patterns is analyzed. Using observations and models, we demonstrate that divergent reforestation patterns can be explained by contrasting time-scales in ecosystem carbon-nitrogen cycles that are influenced by land use legacies. …

Increasing Atmospheric Humidity And Co2 Concentration Alleviate Forest Mortality Risk, Yanlan Liu, Anthony J. Parolari, Mukesh Kumar, Chang-Wei Huang, Gabriel Katul, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Climate-induced forest mortality is being increasingly observed throughout the globe. Alarmingly, it is expected to exacerbate under climate change due to shifting precipitation patterns and rising air temperature. However, the impact of concomitant changes in atmospheric humidity and CO₂ concentration through their influence on stomatal kinetics remains a subject of debate and inquiry. By using a dynamic soil–plant–atmosphere model, mortality risks associated with hydraulic failure and stomatal closure for 13 temperate and tropical forest biomes across the globe are analyzed. The mortality risk is evaluated in response to both individual and combined changes in precipitation amounts and their seasonal …

Mechanical And Economical Impacts Of Adding Polymers Into Asphalt Mixtures, Mena Souliman, Waleed Zeiada, Lubinda Walubita

Civil Engineering Faculty Publications and Presentations

Load associated fatigue cracking is one of the major distress types occurring in flexible pavements. Flexural bending beam fatigue laboratory test has been used for several decades and is considered an integral part of the Superpave advanced characterization procedure. One of the most significant solutions to sustain the fatigue life for an asphaltic mixture is to add sustainable materials such as polymers to the asphalt mixture. A laboratory testing program was performed on two gap-graded mixtures: unmodified and polymer-modified asphalt mixtures. Strain controlled fatigue tests were conducted according to the AASHTO T321 procedure. The results from the beam fatigue tests …

A Hierarchical Modelling Approach For Assessing The Impact Factors Of The Measured Of Mobility And Safety At Intersections, Hiba Eyesha Abou-Kassem

Civil and Environmental Theses

Measuring safety and mobility for various types of intersections is crucial in any transportation study. Many factors contribute to changing the effectiveness of the different types of intersections on mobility and safety. Deciding which type of intersection is most suitable in a particular environ and prevailing traffic conditions depends on the number of crashes, injuries, delay time, etc. This study focuses on two intersection types; signalized intersections and non-signalized intersections (only roundabouts). The aim of this research is to devise a theoretical modeling framework and hence a statistical-based methodology that can be used to assess the safety and mobility measures …

Hydrologic Impacts Of Bioswale Porous Media On Parking Lot Drainage, Jungseok Ho, James Jihoon Kang

Civil Engineering Faculty Publications

Bioswales are stormwater control structures designed stormwater runoff volume and filter stormwater solids and pollutant from surface runoff. Bioswale generally consists of sloped surface ground with native wetland plants to lead stormwater percolation and infiltration, porous media to allow for stormwater retention and stormwater contaminant filtration, and stormwater drain conduit under the porous media. In this study, we monitored the bioswale evaluation factors of stormwater total volume reduction, peak flow rate reduction, and peak time attenuation. It is concluded that, based on a total of 29 monitoring of storm events, pumice is a hydrologically best performing material for the bioswale …

Vulnerability Model Of Residential Structures Subject To Hurricane Induced Wind, Surge And Inundation, Mohammad Baradaranshoraka

Theses and Dissertations

Annualized hurricane-related losses to the built environment in the United States are in the billions of dollars. According to the National Oceanic and Atmospheric Administration, in 2010 39% of the United States population, or 123.3 million inhabitants, lived in a coastal county. This population is expected to increase by 8% from 2010 to 2020. The majority of these people live in buildings prone to hurricanes. The hurricanes can result in wind damage (due to high wind and/or wind-driven rain infiltration) and water damage (due to storm surge and waves or freshwater flooding) to the building and its contents, which are …

Bs News September/October

Building Services Engineering

No abstract provided.

Performance Evaluation And Development Of Mechanistic Empirical Pavement Design Procedure Of Thin Rcc Pavements, Moinul Islam Mahdi

LSU Doctoral Dissertations

With the increasing shale gas exploration, agricultural and logging activities on the low volume roadways, the Louisiana Department of Transportation and Development (LADOTD) and the Louisiana Transportation Research Center (LTRC) are interested in thin applications of Roller Compacted Concrete (RCC) to be used as a design alternative for those low volume roadways having frequently heavy truck trafficking. The objectives of this research were: (1) to evaluate the structural performance and cracking failure mechanism of thin RCC pavements; (2) to develop a mechanistic-empirical based RCC pavement thickness design procedure for LADOTD to use in their low-volume pavement design.

In this study, …

Characterization Of Asphalt Healing And Incorporation In A Fatigue Damage Model, Umme A. Mannan

Civil Engineering ETDs

Healing is defined as the restoration of the material property during the rest period after damage. The healing property of the asphalt binder is opposite to fatigue damage, which occurs due to repeated traffic loading. On the other hand, healing occurs in the rest period between loading. Most of the existing methods for characterizing the fatigue damage and healing of asphalt are empirical in nature and do not consider the mechanism of healing. Although the asphalt concrete is a mixture of asphalt binder, fines and aggregates, most of the healing occurs in the asphalt binder. Therefore, it is important to …

A Decision Making Tool For Incorporating Sustainability Measures In Rigid Pavement Design, Neveen Samy Talaat Soliman

LSU Doctoral Dissertations

One of the most important tools in assessing rigid pavement design sustainability (or environmental impact) is a lifecycle assessment (LCA), which may be applied in any stage of a product’s lifecycle from cradle to grave, such as pavements. Although LCA was the focus of much research and codification by organizations such as the International Organization for Standards and the Society of Environmental Toxicology and Chemistry, limitations exist, such as a) LCA is time consuming; and b) the used data may become outdated, inaccurate, biased, incomplete, and/or expensive to use. These limitations are not a deficiency in LCA as a tool, …

On The Ramberg-Osgood Stress-Strain Model And Large Deformations Of Cantilever Beams, Ronald J. Giardina Jr

LSU New Orleans Theses and Dissertations

In this thesis the Ramberg-Osgood nonlinear model for describing the behavior of many different materials is investigated. A brief overview of the model as it is currently used in the literature is undertaken and several misunderstandings and possible pitfalls in its application is pointed out, especially as it pertains to more recent approaches to finding solutions involving the model. There is an investigation of the displacement of a cantilever beam under a combined loading consisting of a distributed load across the entire length of the beam and a point load at its end and new solutions to this problem are …