Engineering Commons^™

Numerical Approximation Of The Ground Reaction And Support Reaction Curves For Underground Limestone Mines, Jesus Castillo Gomez

Theses and Dissertations--Mining Engineering

Pillar stability has been a matter of study for the last 70 years. The determination of pillar strength had taken different solutions and approaches over that time. This research has led to numerous empirical formulations that have reduced the number of pillar failures worldwide. However, new numerical approaches are being studied. In the last 20 years, the Ground Reaction Curve concept has been examined as a way of understanding the convergence of the rock-mass. Although the Ground Reaction Curve was first introduced in the civil tunneling industry, several authors have introduced the Ground Reaction Curve concept as an approach for …

Designing And Redesigning Products, Processes, And Systems For A Helical Economy, Ryan Bradley, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

The Circular Economy (CE) concept has promised to unlock trillions of dollars in business value while driving a significant reduction in the world’s resource consumption and anthropogenic emissions. However, CE mainly lives in ambiguity in the manufacturing domain because CE does not address the changes needed across all of the fundamental elements of manufacturing: products, processes, and systems. Conceptually, CE is grounded in the concept of closed-loop material flows that fit within ecological limits. This grounding translates into a steady state economy, a result that is not an option for the significant portion of the world living in poverty. Therefore, …

Sloped And Mitered Concrete Headwalls, Kean H. Ashurst Jr., Brad W. Rister, Eileen Grady, Jason K. Ward

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) currently uses several pipe culvert end treatments, including standard headwalls, slope and flared headwalls, sloped and parallel headwalls, and safety metal ends. These treatments, however, can pose a safety hazard to motorists and those performing landscaping work (e.g., mowing). Crash statistics from 2012 through 2016 for Kentucky reveal that 49 fatalities and 148 incapacitating injuries occurred in incidents where culverts/headwalls were coded as the first harmful event on the police report. One solution to the safety hazards associated with standard pipe culvert headwalls is to use sloped and mitered concrete headwalls instead. To evaluate the …

Computational Materials Characterization, Discovery, And Design With High Performance Computing, Qunfei Zhou, Xiaotao Liu, Tyler Maxwell, Thomas John Balk, Matthew J. Beck

Commonwealth Computational Summit

No abstract provided.

Pulsed Laser Beam Welding Of Pd43Cu27Ni10P20 Bulk Metallic Glass, Ling Shao, Amit Datye, Jiankang Huang, Jittisa Ketkaew, Sung Woo Sohn, Shaofan Zhao, Sujun Wu, Yuming Zhang, Udo D. Schwarz, Jan Schroers

Electrical and Computer Engineering Faculty Publications

We used pulsed laser beam welding method to join Pd₄₃Cu₂₇Ni₁₀P₂₀ (at.%) bulk metallic glass and characterized the properties of the joint. Fusion zone and heat-affected zone in the weld joint can be maintained completely amorphous as confirmed by X-ray diffraction and differential scanning calorimetry. No visible defects were observed in the weld joint. Nanoindentation and bend tests were carried out to determine the mechanical properties of the weld joint. Fusion zone and heat-affected zone exhibit very similar elastic moduli and hardness when compared to the base material, and the weld joint shows high …

Benefits From Constructability Reviews, Nikiforos Stamatiadis, Roy Sturgill, Kiriakos Amiridis

Civil Engineering Faculty Publications

Constructability review is a process used during project design to infuse construction knowledge into the design process. There is industry impetus encouraging early construction involvement in project development. State transportation agencies often have to abide by legislation restricting these procurement methods leaving construability review as the only opportunity for early construction involvement. Staffing and budgetary constraints lead to state transportation agencies being very cautious in the practices and processes they implement that seemingly lie outside the main missions of project development and delivery. Without straightforward and documented savings of constructability review processes, these methods may also be eliminated. After streamlining …

Transition Zone Design Final Report, Nikiforos Stamatiadis, Adam J. Kirk, Andrea Cull, Austin Dahlem

Kentucky Transportation Center Research Report

The purpose of this report is to document the activities of the research effort and present the findings of the work accomplished. Transition zone is the area in which it is communicated to drivers that the roadway environment is changing (i.e., from rural to built-up) and that their speed should change as well. This study evaluated treatments that could advise drivers to this. Based on the study findings, it is recommended to add additional speed warning sites to such transition zones.

Tools For Applying Constructability Concepts To Project Development (Design), Nikiforos Stamatiadis, Paul Goodrum, Emily Shocklee, Roy Sturgill, Chen Wang

Kentucky Transportation Center Research Report

The purpose of this report is to document the activities of Phases I and II of the research effort and present the findings of the work accomplished. Phase I developed the Constructability Review Database for the Kentucky Transportation Cabinet and Phase II conducted a benefit analysis of the constructability review process. The database provides the basis for entry and collection of constructability reviews and allows for the identification of trends leading to potential improvements of the process. The database can be used to summarize activities, generate reports for a project, and be capable of quantifying the benefits from the process. …

Tools For Applying Constructability Concepts To Project Development (Design), Nikiforos Stamatiadis, Paul Goodrum, Emily Shocklee, Chen Wang

Kentucky Transportation Center Research Report

The purpose of this report is to document the activities of Phase I of the research effort and present the development of the Constructability Review Database developed for the Kentucky Transportation Cabinet. The database provides the basis for entry and collection of constructability reviews and allows for the identification of trends leading to potential improvements of the process. The database can be used to summarize activities, generate reports for a project, and be capable of quantifying the benefits from the process.

A Case Study Analysis Of The Kentucky Transportation Cabinet’S Design/Build Pilot Projects, Paul M. Goodrum, Mohammad Moin Uddin, Bradley J. Faulkenberg

Kentucky Transportation Center Research Report

The current economic climate has forced transportation agencies to evaluate opportunities to save money. One possible opportunity lies in Design/Build (DB) delivery. In 2006, with the approval of the Kentucky General Assembly, The Kentucky Transportation Cabinet selected ten projects to be developed through the Design/Build method. DB delivery offers many attainable advantages, the most notable being expedited delivery. The research described herein presents a case study of these DB pilot projects in order to capture lessons learned on the use of the DB delivery method on future projects. In order to determine which projects are suitable for DB delivery, a …

Resilient Modulus Of Compacted Crushed Stone Aggregate Bases, Tommy C. Hopkins, Tony L. Beckham, Charlie Sun

Kentucky Transportation Center Research Report

In recent years, the American Association of State Highway Transportation Officials (AASHTO) has recommended the use of resilient modulus for characterizing highway materials for pavement design. This recommendation evolved as result of a trend in pavement design of using mechanistic models. Although much progress has been made in recent years in developing mathematical, mechanistic pavement design models, results obtained from those models are only as good as the material parameters used in the models. Resilient modulus of aggregate bases is an important parameter in the mechanistic models. The main goal of this study was to establish a simple and efficient …

Bearing Capacity Analysis And Design Of Highway Base Materials Reinforced With Geofabrics, Tommy C. Hopkins, Liecheng Sun, Mikhail E. Slepak

Kentucky Transportation Center Research Report

The primary objective of this study was to develop and implement mathematical bearing capacity models originally proposed by Hopkins (1988, 1991) and Slepak and Hopkins (1993; 1995). These advanced models, which are based on limit equilibrium and are operated together, can be used to analyze the bearing capacity, or stability, of early construction of loads on a single layer of material, two-layered problems involving a layer of base aggregate and subgrade, and a foundation involving multiple layers of different materials, such as a flexible asphalt pavement. A Prandlt-type shear surface is used in the model analyses of layered foundations. In …

Resilient Modulus Of Kentucky Soils, Tommy C. Hopkins, Tony L. Beckham, Charlie Sun, Bixian Ni

Kentucky Transportation Center Research Report

In recent years, the American Association of State Highway Transportation Officials (AASHTO) has recommended the use of resilient modulus for characterizing highway materials for pavement design. This recommendation evolved as of a result of a trend in pavement design of using mechanistic models, which are based on the theory of elasticity (layered elastic analysis) or linear and non-linear, finite elements (and finite difference methods), or a combination of both of those theoretical approaches. Although much progress has been made in recent years in developing mathematical, mechanistic pavement design models, results obtained from those models are only as good as the …

Pavement Design Guide: A Short Course, Kentucky Transportation Center

Kentucky Transportation Center Research Report

The purpose of this short course is to provide information to the registered engineer (with no previous background in pavement design or pavement technology) on the structural design of pavements. Included in this course is a summary of background information on the materials used in pavement construction and on the history and evolution of pavement design. Included with this course is an updated Design Guide or catalog to be used for designing new pavements in Kentucky. The intent of the guide or catalog is to provide the road\\ a) designer with a simplified, straightforward methodology for developing structural designs of …

Ventilation System Design Parameters For Greenhouses For Tobacco Production, R. S. Gates, George A. Duncan

Agricultural Engineering Extension Updates

Methods for germination and initial growth of tobacco have changed rapidly in recent years, moving from outside float beds into double-layer plastic greenhouses. Typically, these "tobacco greenhouses" consist of sidewall curtains, which run the entire length of both sides of the house. They may also have modest mechanical ventilation.

Ventilation of greenhouse structures is a mature field, with engineering practices for proper design given by numerous organizations including ASAE. In this article we briefly outline the important features of ventilation of concern to tobacco greenhouse operators.

Embankment Construction Using Shale, Tommy C. Hopkins, Tony L. Beckham

Kentucky Transportation Center Research Report

Shales have been used extensively in the construction of highway embankments, and other earthen structures, because of the vast amounts of these materials located in many areas of the country and the lack of economical and alternate available materials. Because shales exhibit a wide range of engineering properties and behaviors, many problems have occurred. Numerous shale embankment failures have occurred generally some 1 to 10 years after construction. Settlements of 1 to 3 feet (0.3 - 0.9 m) have been observed in many old embankments and required numerous asphaltic overlays. Shale embankments that settle continuously have been observed to fail …

Subsurface Drainage Of Highway Pavements, David Q. Hunsucker, Bobby W. Meade

Kentucky Transportation Center Research Report

Properly designed and constructed drainage layers can be used for effective control of surface water infiltration. Former pavement design methods often have resulted in base courses that have not drained well, thereby resulting in some premature failures of the pavement structure. The Kentucky Department of Highways is currently reviewing proposed guidelines for design of highway pavements. The guidelines propose the use of open graded, free draining, aggregate bases for controlling infiltrated surface water. However, interim design guidelines do not specifically address the design of aggregate drainage blankets. The purpose of this study was to develop recommendations relating to the specification, …

Cost Estimating And Forecasting For Highway Work In Kentucky [1996], James D. Stevens, Jennifer R. Walton

Kentucky Transportation Center Research Report

There is a need for better cost estimating and forecasting for highway work in the Commonwealth of Kentucky. KRS45.245 grants the Interim Joint Committee on Transportation oversight of the biennial highway plan, including a review of all authorized highway project phases that exceed their estimates by 15%. In recent years, the Kentucky Transportation Cabinet has suffered the loss of many resources necessary to produce good cost estimates.

Estimates developed using current methods are not sufficiently accurate to preclude cost overruns in excess of 15%. Over the 1992 and 1994 bienniums, 362 overruns totaling $162,487,511 have been submitted to the Committee. …

Best Practices For Commercial Vehicle Monitoring Facilities Design, Nikiforos Stamatiadis, R. Clark Graves, John E. Schmidt

Kentucky Transportation Center Research Report

The great technological advances that were made over the last decade in monitoring traffic and the increased emphasis on highway safety for truck traffic have prompted a need to determine more effective ways to monitor and inspect truck traffic. Commercial Vehicle Monitoring (CVM) facilities provide the highway community with the means of supervising truck traffic. However, in an era with limited funds and space for roadway expansion. some consideration must be given to the types of facilities needed and the most efficient way to spend the available funds. Hence, a research study was initiated to determine the successful practices for …

Modification Of Highway Soil Subgrades, Tommy C. Hopkins, Tony L. Beckham, David Q. Hunsucker

Kentucky Transportation Center Research Report

Major study objectives were to develop highway pavement subgrade stabilization guidelines, examine long-term benefits of chemical stabilizers, such as cement, hydrated lime, and two byproducts from industrial processes, and to establish a subgrade stabilization program in Kentucky. In developing a program, a number of design and construction issues had to be resolved. Factors affecting subgrade behavior are examined. Changes in moisture content and CBR strengths of untreated and chemically treated subgrades at three experimental highway routes were monitored over a 7- year period. CBR strengths of the untreated subgrades decreased dramatically while moisture contents increased. CBR strengths of subgrade sections …

Selection Of Design Strengths Of Untreated Soil Subgrades And Subgrades Treated With Cement And Hydrated Lime, David Q. Hunsucker, Tony L. Beckham

Kentucky Transportation Center Research Report

Selection of design strengths of soil subgrades and subgrades treated with cement or hydrated lime is a problem in pavement design analysis and construction because a variety of different types of soils may exist in a highway corridor and a wide range of different strengths may exist after the soils are compacted to form the pavement subgrade. The selected subgrade strength will largely affect the pavement thickness obtained from the design analysis, the future pavement performances, and the overall bearing capacities of the subgrade during construction and the pavement structure after construction. In developing the proposed selection scheme, a newly …

Micro-Sprinkler And Fan Cooling For Dairy Cows: Practical Design Considerations, Larry W. Turner, Richard C. Warner, John P. Chastain

Agricultural Engineering Extension Publications

Research and on-farm demonstrations have shown that micro-sprinklers, spray jets and fan cooling systems can be effective in relieving heat stress in dairy cows under hot, humid conditions. Based on these results, many dairymen are considering installing sprinkler and fan cooling. Several Kentucky dairymen have already installed sprinkler cooling systems, but they could improve their performance by modifying them to take into account the principles involved and the components used in sprinkler and fan cooling.

Bearing Capacity Analysis Of Pavements, Tommy C. Hopkins

Kentucky Transportation Center Research Report

A multilayered, mathematical model for analyzing the ultimate bearing capacity of soil subgrades and asphalt pavements is presented. Theoretical considerations and mathematical derivations of limit equilibrium equations, based on plasticity principles, for analyzing the ultimate bearing capacity of soil subgrades and partially completed asphalt pavements, and the extension of these equations to the analyses of asphalt pavements composed of multiple layers, are presented. The model is unique since shear strength parameters, Φ and c, (the angle of internal friction and cohesion, respectively) are used to describe each layer of material of the pavement structure and a factor of safety against …

Excessive Beam Deflections On The Ky-52 Bridge Over Dix River (Boyle-Garrard County Line), Theodore Hopwood Ii, Vishwas G. Oka, David Q. Hunsucker, James H. Havens

Kentucky Transportation Center Research Report

Upon rehabilitation, beams and deck of the Ky 52 bridge over Dix River were observed to have excessive deflections. An investigation of the problem included field inspections, structural analyses, and interviews with relevant KYDOH and other personnel.

Field measurements were made of the beam deflections. Those were compared to construction field measurements and dead-load calculations.

The beam deflection problem is attributed to 1) a failure to provide for sufficient camber in the beams to accommodate for construction dead loads, and 2) pre-existing sags in the beams when placed prior to casting the deck. Part of the deck deflection problem can …

Design Of Highway Embankment On Unstable Natural Slopes, Charles S. Bishop, Donald W. Armour Jr., Tommy C. Hopkins

Kentucky Transportation Center Research Report

Sections of the new Alexandria-Ashland (M) highway in northeastern Kentucky must be located on and through natural slopes of the Kope and Crab Orchard Formations that consist mainly of shales. Numerous highway embankment and cut slope failures have occurred In these two geologic formations In past years. The shales of these formations have very poor and undesirable engineering properties. Many stability problems encountered with the Kope and Crab Orchard shales are caused primarily by the tendency of those shales to breakdown when exposed to water and produce clays and clayey silts of relatively low shear strengths. Construction of highway embankments …

Hydraulic Design Algorithms For Upgrading And Enhancing Water Distribution Systems, Don J. Wood, William T. Gilbert

KWRRI Research Reports

The primary objective of this work was to develop algorithms for directly determining design characteristics for effectively enhancing, modifying or adding to existing water distribution systems. This is accomplished by modifying the basic hydraulic network equations to explicitly determine required design parameters to just meet specified conditions. Initially work was completed on directly determining pipeline diameters and directly determining pipeline and network resistance characteristics. This work was published in technical journals and established the feasibility of the approach but did not demonstrate the scope and versitility of the proposed approach. In this report a general approach is developed and tested …

Stability Of Embankments On Clay Foundations, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Ninety-one well-documented geotechnical failures are reviewed. The case studies involved the failure of embankments, footings and load tests, excavated slopes, and natural slopes. Seventy-five of the geotechnical failures had been analyzed using total stress analysis. Sixteen of the case failures had been analyzed using effective stress analysis. Based on a review of these case studies, there are discrepancies between predicted and actual stabilities of geotechnical structures and there is a tendency tu overestimate the factor of safety. Differences that may arise between predicted and actual performances are discussed and examined and guidelines are proposed for evaluating the potential of successfully …

Long-Term Movements Of Highway Bridge Approach Embankments And Pavements, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Long-term movements of highway bridge approach embankments and pavements are described and factors that may lead to settlement of highway bridge approach pavements are discussed. Six case histories are presented. The bridge approach sites were observed at different times during the period 1966 to 1985. At four sites, lateral movements, measured from slope inclinometers, of the approach embankments were monitored over time periods ranging from 8 to 14 years. Settlements of the highway bridge approaches were monitored some three to four years after paving. Estimated and observed settlements of the foundations at the study sites were obtained for a length …

Unstable Subgrade, I 65, Hardin County (I 65 - 5 (17) 92; Fsp 047-0065-091-0396), Tommy C. Hopkins, Gary W. Sharpe

Kentucky Transportation Center Research Report

During construction of the southbound lanes of I 65, Stations 120+00 to 218+00, in Hardin County, Kentucky, near Elizabethtown, large deformations were observed when dense-graded aggregate (DGA) base courses were loaded with construction traffic. Rutting and cracking of the DGA also was noticeable. A study was performed to determine the causes of the unstable subgrade and base, recommend remedial actions, and evaluate the effectiveness of the remedial measures. The stability, or bearing capacity, of the unstable pavement was determined for different construction stages and combinations of pavement layer thicknesses using a relatively new stability model HOPK-I. The stability of the …

A Review And Analysis Of Pile Design, David L. Allen

Kentucky Transportation Center Research Report

A review of lateral load design of piles is presented. It appears many different methods and allowable lateral loads are permitted by the states. One particular method is discussed in detail, and from that method two charts are presented that relate pile deflection to lateral load. Recommendations are given on design criteria for lateral loads.

A review of allowable axial stresses is also presented. The results of a brief finite element analysis of pile tip settlement versus load for various conditions are also presented. These results are compared to data obtained from the literature. Recommendations on maximum allowable axial stress …