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Full-Text Articles in Engineering

Development Of A 3-D Finite Element Program For Pavement Analysis, Volume 2: Appendix 2, Tatsaba Nilaward, Chiang Shih, Thomas D. White, E. C. Ting Jan 1998

Development Of A 3-D Finite Element Program For Pavement Analysis, Volume 2: Appendix 2, Tatsaba Nilaward, Chiang Shih, Thomas D. White, E. C. Ting

JTRP Technical Reports

A three dimensional finite element program is developed for the analysis of pavement systems. An explicit approach of the finite element analysis is adopted. This approach results in a vector formulation of the equation of motion. Large displacement is considered through the use of a co-rotational approach which considers small deformations and large rotations of the elements. For the convenience of application a two dimensional finite element program is also developed. An eight-node isoperimetric solid element is used for the three dimensional analysis, and a four-node element for the two dimensional analysis. Loading conditions are verified for static ramp and …


Controlling Air Content In Concrete That Is Being Pumped, A Synthesis Study, Charles F. Scholer, Jay Grossman Jan 1998

Controlling Air Content In Concrete That Is Being Pumped, A Synthesis Study, Charles F. Scholer, Jay Grossman

JTRP Technical Reports

Changes in the air content of fresh concrete that is being pumped can occur at a number of places. These locations include the initial loading of the concrete into the pump hopper, as it passes through the pump line, and when it exits the line. This synthesis reviews the findings of recent research studies which deal with air content change in pumped concrete and summarizes methods of reducing air loss caused by handling. Three main mechanisms by which air content is lost in fresh concrete that is being pumped have been noted. These factors include the high-pressure dissolution of air …


A Methodology For The Analysis Of Its Impacts On Mobility, Air Quality, And Land Use, Kumares C. Sinha, Srinivas Peeta, Muhammed Amer Sultan, Kamalakar Poonuru, Nadine-Jenelle K. Richards Jan 1998

A Methodology For The Analysis Of Its Impacts On Mobility, Air Quality, And Land Use, Kumares C. Sinha, Srinivas Peeta, Muhammed Amer Sultan, Kamalakar Poonuru, Nadine-Jenelle K. Richards

JTRP Technical Reports

The Indiana Department of Transportation (INDOT) is currently implementing (or has implemented) several components of Intelligent Transportation Systems (ITS). This includes a mini Advanced Traffic Management Systems (ATMS) implemented on a three-mile stretch of the Borman Expressway to evaluate advanced non-intrusive sensor systems and the associated communication infrastructure for the installation of a full-scale ATMS on the 16-mile stretch of the Borman Expressway. Potential specific ITS technologies that are either being implemented or are being considered include pre-trip information, en-route information, variable message signs, and Hoosier Helpers. It is expected that the implementation of various ITS technologies on the Borman …


A Tool For Evaluating Access Control On High Speed Urban Arterials, Part I, Henry C. Brown, Samuel Labi, Andrzej P. Tarko, Jon D. Fricker Jan 1998

A Tool For Evaluating Access Control On High Speed Urban Arterials, Part I, Henry C. Brown, Samuel Labi, Andrzej P. Tarko, Jon D. Fricker

JTRP Technical Reports

A highway system serves two needs: mobility and accessibility. Access control techniques are used to restrict access to the highway and improve vehicle flow. The objective of this research was to develop a comprehensive procedure to evaluate access control alternatives. The procedure includes the design and quantitative evaluation of alternatives to select the best one. Evaluation of each alternative includes prediction of turning volumes, delays, crash rates, and economic effectiveness. Several existing models predict traffic delays for signalized intersections and for minor streams at unsignalized intersections. Models are needed to predict delays of arterial streams caused by minor streams at …


A Tool For Evaluating Access Control On High Speed Urban Arterials, Part Ii: User's Manual, Henry C. Brown, Samuel Labi, Andrzej P. Tarko, Jon D. Fricker Jan 1998

A Tool For Evaluating Access Control On High Speed Urban Arterials, Part Ii: User's Manual, Henry C. Brown, Samuel Labi, Andrzej P. Tarko, Jon D. Fricker

JTRP Technical Reports

A highway system serves two needs: mobility and accessibility. Access control techniques are used to restrict access to the highway and improve vehicle flow. The objective of this research was to develop a comprehensive procedure to evaluate access control alternatives. The procedure includes the design and quantitative evaluation of alternatives to select the best one. Evaluation of each alternative includes prediction of turning volumes, delays, crash rates, and economic effectiveness. Several existing models predict traffic delays for signalized intersections and for minor streams at unsignalized intersections. Models are needed to predict delays of arterial streams caused by minor streams at …


An Integrated Transportation Use Modeling System For Indiana; Implementation Report And User's Manual, Andrew Ying-Ming Yen, Jon D. Fricker Jan 1998

An Integrated Transportation Use Modeling System For Indiana; Implementation Report And User's Manual, Andrew Ying-Ming Yen, Jon D. Fricker

JTRP Technical Reports

The principle objective of this research was to develop an integrated model to represent the interrelationships between land use and transportation, subject to the requirements of the ISTEA of 1991 and the CAAA of 1990. The integrated model includes two major parts: a land-use allocation module and a travel demand module. An interface module has also been built to transform data between these two modules. The land-use allocation module consists of a residential location model, an employment location model, a land use potential model, and a land consumption model. One unique feature of the residential and employment location models is …


An Integrated Transportation Use Modeling System For Indiana, Andrew Ying-Ming Yen, Jon D. Fricker Jan 1998

An Integrated Transportation Use Modeling System For Indiana, Andrew Ying-Ming Yen, Jon D. Fricker

JTRP Technical Reports

The principle objective of this research was to develop an integrated model to represent the interrelationships between land use and transportation, subject to the requirements of the ISTEA of 1991 and the CAAA of 1990. The integrated model includes two major parts: a land-use allocation module and a travel demand module. An interface module has also been built to transform data between these two modules. The land-use allocation module consists of a residential location model, an employment location model, a land use potential model, and a land consumption model. One unique feature of the residential and employment location models is …


Automation And Standardization Of Measuring Moisture Content And Density Of Soil Using The Technique Of Time Domain Reflectometry, Wei Feng, Chih-Ping Lin, Richard J. Deschamps, Vincent P. Drnevich Jan 1998

Automation And Standardization Of Measuring Moisture Content And Density Of Soil Using The Technique Of Time Domain Reflectometry, Wei Feng, Chih-Ping Lin, Richard J. Deschamps, Vincent P. Drnevich

JTRP Technical Reports

The methodology developed by Siddiqui and Drnevich (1995) for measuring soil water content and density using Time Domain Reflectometry (TDR) was extended for routine use in the quality control testing of compacted soils. The objectives of the study were to develop computer software to automate data interpretation and data reduction, develop prototype equipment for field use, compare the results of the TDR method with the sand cone and nuclear density methods on actual construction sites and develop draft specifications for ASTM and AASHTO. New prototype equipment was developed for compaction quality control testing. Waveform interpretation and data reduction were automated …


Assessing And Updating Indot's Traffic Monitoring System For Highways (2 Volumes), Samuel Labi, Jon Fricker Jan 1998

Assessing And Updating Indot's Traffic Monitoring System For Highways (2 Volumes), Samuel Labi, Jon Fricker

JTRP Technical Reports

This study evaluates the existing resources and procedures of INDOT’s current traffic monitoring program, with the objective of transforming this program into a comprehensive Traffic Monitoring System for Highways (TMS/H). Reliable traffic data is a valuable input for studies and decision-making at various levels and in various phases of highway management including planning and design, finance and taxation, legislation and safety. The nature and scope of the various components comprising a TMS/H for any state were identified in available literature such as the Federal Register and Traffic Monitoring Guide. A complete inventory of the existing resources (personnel and equipment) and …


Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord Gale, Jerry L. Pitt Jan 1998

Evaluation Of Toxicity, Bioavailability And Speciation Of Lead, Zinc And Cadmium In Mine/Mill Wastewaters, Mujde Erten-Unal, Bobby G. Wixson, Nord Gale, Jerry L. Pitt

Civil & Environmental Engineering Faculty Publications

The toxicity of common compounds of lead, cadmium and zinc was evaluated in waters similar to that found in the world's largest lead producing area in Missouri. Static, acute toxicity tests were performed using fathead minnows (Pimephales promelas) and water fleas (Daphnia magna) respectively. Test organisms were subjected to varying amounts of sulfide, carbonate, chloride and sulfate salts of lead, zinc and cadmium mixed in hard, alkaline waters typical to this region. Median lethal concentrations were calculated using nominal versus measured metal concentrations. Measured metal concentrations included four different metal fractionation (extraction/filtration) techniques at different pH …


Embankment Construction Using Shale, Tommy C. Hopkins, Tony L. Beckham Jan 1998

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 …


Kentucky Traffic Accident Facts 1998 Report, Kentucky Transportation Center, Kentucky State Police Jan 1998

Kentucky Traffic Accident Facts 1998 Report, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY’S TRAFFIC ACCIDENT FACTS report for 1998 is based on accident reports submitted to the Accident Unit housed in the Kentucky State Police Information Services Branch, Records Section. As required by Kentucky Revised statutes 189.635, “every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize date on traffic accidents” for such purposes as will improve the traffic safety program in the Commonwealth.” Data contained in …


Bs News Jan 1998

Bs News

Building Services Engineering

No abstract provided.


Strength And Durability Of Concrete: Effects Of Cement Paste-Aggregate Interfaces, Part Ii: Significance Of Transition Zones On Physical And Mechanical Properties Of Portland Cement Mortar, Turng-Fang F. Lee, Menashi D. Cohen Jan 1998

Strength And Durability Of Concrete: Effects Of Cement Paste-Aggregate Interfaces, Part Ii: Significance Of Transition Zones On Physical And Mechanical Properties Of Portland Cement Mortar, Turng-Fang F. Lee, Menashi D. Cohen

JTRP Technical Reports

This research was based on a two-part basic research investigation studying the effects of cement paste-aggregate interfaces (or interfacial transition zones-HZ) on strength and durability of concrete. Part I dealt with the theoretical study and Part II dealt with the experimental. Part I, the theoretical part, illustrates the effect of ITZ on the concrete properties by assuming its elastic moduli to be varied continuously in the region. A four-phase composite model is employed and three functions are chosen to model the moduli variation in the ITZ. A theoretical solution for an n-layered spherical inclusion model is used to estimate the …


Integration Of Real-Time Air Pollution Parameters Into The Decision Making Process Regarding Highway Construction Work Zone Traffic Flow Requirements (Phase 1), Ouattara Fatogoma, Todd A. Premo, Robert Bertram Jacko Jan 1998

Integration Of Real-Time Air Pollution Parameters Into The Decision Making Process Regarding Highway Construction Work Zone Traffic Flow Requirements (Phase 1), Ouattara Fatogoma, Todd A. Premo, Robert Bertram Jacko

JTRP Technical Reports

The Midac Fourier Transform Infrared air monitoring system was used to measure real-time vehicular exhaust emission concentrations of carbon monoxide (CO) and hydrocarbons (HCs) during the Purdue Vehicle Emission Monitoring and Modeling Project (PVEMP) conducted in spring and summer 1997. The experiments took place on the Borman Expressway, in Gary. Indiana and on 1-65, south of Lafayette, Indiana Concurrently, two speed-readings were acquired from the passing vehicles in the vicinity of the air monitoring system using a hand-held laser gun. The speeds were integrated to determine the speeds and accelerations of the passing vehicles at the spectrometer. An 8-mm camcorder …


Modeling And Optimization Of The Indiana Lane Merge Control System On Approaches To Freeway Work Zones, Part I, Andrzej P. Tarko, Sreenivasulu R. Kanipakapatnam, Jason S. Wasson Jan 1998

Modeling And Optimization Of The Indiana Lane Merge Control System On Approaches To Freeway Work Zones, Part I, Andrzej P. Tarko, Sreenivasulu R. Kanipakapatnam, Jason S. Wasson

JTRP Technical Reports

Severe traffic turbulence on entry sections of freeway work zones increases the delays and risk of crash. A new Indiana Department of Transportation system called Indiana Merge Lane System (IMLS) creates a dynamic no passing zone on the approach to the freeway work zone through the sequence of DO NOT PASS signs. The system is thought to encourage drivers to switch lanes well upstream of the discontinuous lane taper where the merging maneuver is safer and less intrusive. The IMLS is expected to impact drivers’ behavior, their perception of the traffic conditions, and traffic safety.

This research is focused on: …


Strength And Durability Of Concrete: Effects Of Cement Paste-Aggregate Interfaces, Part I: Theoretical Study On Influence Of Interfacial Transition Zone On Properties Of Concrete Materials, Yiguo Zhang, Wai-Fah Chen Jan 1998

Strength And Durability Of Concrete: Effects Of Cement Paste-Aggregate Interfaces, Part I: Theoretical Study On Influence Of Interfacial Transition Zone On Properties Of Concrete Materials, Yiguo Zhang, Wai-Fah Chen

JTRP Technical Reports

This research was based on a two-part basic research investigation studying the effects of cement paste-aggregate interfaces (or interfacial transition zones-HZ) on strength and durability of concrete. Part I dealt with the theoretical study and Part II dealt with the experimental. Part I, the theoretical part, illustrates the effect of ITZ on the concrete properties by assuming its elastic moduli to be varied continuously in the region. A four-phase composite model is employed and three functions are chosen to model the moduli variation in the ITZ. A theoretical solution for an n-layered spherical inclusion model is used to estimate the …


Assessing And Updating Indot's Traffic Monitoring System For Highways, Volume 1 - Main Report, Samuel Labi, Jon D. Fricker Jan 1998

Assessing And Updating Indot's Traffic Monitoring System For Highways, Volume 1 - Main Report, Samuel Labi, Jon D. Fricker

JTRP Technical Reports

No abstract provided.


Geotechnical Performance Of Highway Embankment Constructed Using Waste Foundry Sand, Patrick J. Fox, David G. Mast Jan 1998

Geotechnical Performance Of Highway Embankment Constructed Using Waste Foundry Sand, Patrick J. Fox, David G. Mast

JTRP Technical Reports

The purpose of this study was to evaluate the use of waste foundry sand (WFS) as a highway embankment material in a fullscale field demonstration project. This evaluation included geotechnical concerns, such as deformation, strength, hydraulic conductivity, and ease of construction. The report presents an introduction and previous research concerning WFS use in highway construction. A geotechnical laboratory testing program characterized the WFS used in the project, which was a waste product of Auburn Foundry, Inc., located in Auburn, Indiana. This study was also a part of the FHWA Priorities Technology Program. The project site was a 275 m section …


Implementation Of Subgrade Resilient Modulus For Pavement (2 Volumes), A. G. Altschaeffl, Ross A. Duckworth, M. K. Clough Jan 1998

Implementation Of Subgrade Resilient Modulus For Pavement (2 Volumes), A. G. Altschaeffl, Ross A. Duckworth, M. K. Clough

JTRP Technical Reports

This Implementation Project had two purposes: 1) to update the INDOT Division of Materials and Tests’ laboratory equipment and train personnel to properly conduct the testing for subgrade resilient modulus in accordance with new AASHTO testing protocol (AASHTO T0294-94(; 2) to educate and train the geotechnical engineering section in the procedures for determining the design resilient modulus with minimum required testing, while using the database of the previous report on this subject, FHWA/IN/JHRP-92/23, “Subgrade Resilient Modulus for Pavement Design and Evaluation,” Part I of the Final Report, the detailed “Laboratory Procedures Manual,” has been written for use by laboratory technicians …


Implementation Of Subgrade Resilient Modulus For Pavement: Laboratory Procedures Manual (2 Volumes), A. G. Altschaeffl, Ross A. Duckworth, M. K. Clough Jan 1998

Implementation Of Subgrade Resilient Modulus For Pavement: Laboratory Procedures Manual (2 Volumes), A. G. Altschaeffl, Ross A. Duckworth, M. K. Clough

JTRP Technical Reports

This Implementation Project had two purposes: 1) to update the INDOT Division of Materials and Tests’ laboratory equipment and train personnel to properly conduct the testing for subgrade resilient modulus in accordance with new AASHTO testing protocol (AASHTO T0294-94(; 2) to educate and train the geotechnical engineering section in the procedures for determining the design resilient modulus with minimum required testing, while using the database of the previous report on this subject, FHWA/IN/JHRP-92/23, “Subgrade Resilient Modulus for Pavement Design and Evaluation,” Part I of the Final Report, the detailed “Laboratory Procedures Manual,” has been written for use by laboratory technicians …


Identification And Quantification Of Radionuclides In Coal Ash, James E. Alleman, Franklyn M. Clikeman, Thomas Skronski Jan 1998

Identification And Quantification Of Radionuclides In Coal Ash, James E. Alleman, Franklyn M. Clikeman, Thomas Skronski

JTRP Technical Reports

One of the important environmental issues raised recently in regard to coal ash reuse for highway construction purposes (e.g., embankment development) is that of worker, and public, exposure to radiation which might possibly be emitted by these types of residuals. Radiation emission is, in fact, a natural phenomenon for most materials, both natural and man-made, but in the case of coal ash residuals the process of combustion produces an inevitable concentration of radionuclides from the original virgin coal. INDOT’s corresponding environmental concern consequently focuses on the following basic question: does this magnification of radionuclides found within these coal ash residuals …


Modeling And Optimization Of The Indiana Land Merge Control System On Approaches To Freeway Work Zones, Part I: Implementation Report; Part Ii: Manual Of The Indiana Lane Merge Control System (2 Volumes), Andrzej P. Tarko, Sreenivasulu R. Kanipakapatnam, Jason S. Wasson Jan 1998

Modeling And Optimization Of The Indiana Land Merge Control System On Approaches To Freeway Work Zones, Part I: Implementation Report; Part Ii: Manual Of The Indiana Lane Merge Control System (2 Volumes), Andrzej P. Tarko, Sreenivasulu R. Kanipakapatnam, Jason S. Wasson

JTRP Technical Reports

Severe traffic turbulence on entry sections of freeway work zones increases the delays and risk of crash. A new Indiana Department of Transportation system called Indiana Merge Lane System (IMLS) creates a dynamic no passing zone on the approach to the freeway work zone through the sequence of DO NOT PASS signs. The system is thought to encourage drivers to switch lanes well upstream of the discontinuous lane taper where the merging maneuver is safer and less intrusive. The IMLS is expected to impact drivers’ behavior, their perception of the traffic conditions, and traffic safety. This research is focused on: …


Performance Evaluation Of A Highway Embankment Constructed Using Waste Foundry Sand, Barry K. Partridge, James E. Alleman Jan 1998

Performance Evaluation Of A Highway Embankment Constructed Using Waste Foundry Sand, Barry K. Partridge, James E. Alleman

JTRP Technical Reports

Over 9 million Mg of waste foundry sands (WFS) are produced annually in the United States as a by-product of the metal casting industry. The majority of WFS are deposited in restricted or sanitary waste landfills. Considerable savings is available to the metal casting industry through the development of reuse applications for their WFS and generators are often willing to provide WFS to a job site at no cost to the end user. Laboratory investigations have indicated that WFS from ferrous foundries can provide the necessary engineering properties for a highway embankment and that the MicrotoxTM bioassay test can be …


Acid Characteristics Of Dissolved Organic Matter In Wastewater, Jianmin Wang, C. P. Huang, Herbert E. Allen, Luis R. Takiyama, Ira Poesponegoro, Haryanto Poesponegoro, Dan Pirestani Jan 1998

Acid Characteristics Of Dissolved Organic Matter In Wastewater, Jianmin Wang, C. P. Huang, Herbert E. Allen, Luis R. Takiyama, Ira Poesponegoro, Haryanto Poesponegoro, Dan Pirestani

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The presence of dissolved organic matter (DOM) in a wastewater treatment system can significantly affect the uptake of heavy metals by sludge particulates. The characteristics of DOM, its concentration, and the solution pH are important parameters governing the heavy metals uptake reaction. The characteristics of DOM of various wastewater and sludge (primary, secondary, and tertiary) samples collected from four municipal wastewater treatment plants were investigated. Results showed that the dissolution of DOM from sludge is significantly affected by pH and suspended solids concentration. Results also showed that DOM contains two discrete acid groups that are available for metals complexation. The …


Natural Treatment And On-Site Processes, Kevin D. White, Joel Gerard Burken Jan 1998

Natural Treatment And On-Site Processes, Kevin D. White, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.


Multiple Objective Structural Optimization With Genetic Algorithm And Fuzzy Logic, Franklin Y. Cheng, Dan Li, Jeffrey J.F. Ger Jan 1998

Multiple Objective Structural Optimization With Genetic Algorithm And Fuzzy Logic, Franklin Y. Cheng, Dan Li, Jeffrey J.F. Ger

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper presents a constrained multiobjecthe optimzation method in the form of a robust, practical, problem-independent algorithm, and investigates the effect of multiobjective optimization on structural design. The study includes properties and characteristics of multiobjective optimization and solutions. Design objectives, constraints, and design variables as well as their effect on structural design and behavior are investigated. Fuzzy set theory is also included to construct a fuzzy constrained environment. Two new genetic algorithm operators — multiobjective fitness function and niche method -- are proposed. A new genetic algorithm process, Pareto set filter, is added to genetic algorithms. A 10-story setback building …


Genetic Algorithm Development For Multiobjective Optimization Of Structures, Franklin Y. Cheng, Dan Li Jan 1998

Genetic Algorithm Development For Multiobjective Optimization Of Structures, Franklin Y. Cheng, Dan Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Genetic algorithms (GAs) have the characteristic of maintaing a population of solutions and can search in a parallel manner for many nondominated solutions. These features coincide with the requirement of seeking a Pareto optimal set in a multiobjective (multicriteria, vector) optimization problem. The retionale for multiobjective optimization via GAs is that at each generation, the fitness of each individual is defined according to its nondominated property. Because nondominated individuals are assigned the highest fitness values, the convergence of a population will go th the nondominated zone: the Pareto optimal set. Based on this concept, a Pareto, GA, whose goal is …


Contribution Of Externally Bonded Frp To Shear Capacity Of Rc Flexural Members, Ahmed Khalifa, William J. Gold, Antonio Nanni, M. I. Abdel Aziz Jan 1998

Contribution Of Externally Bonded Frp To Shear Capacity Of Rc Flexural Members, Ahmed Khalifa, William J. Gold, Antonio Nanni, M. I. Abdel Aziz

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Fiber reinforced polymer (FRP) materials are continuing to show great promise for use in strengthening reinforced concrete structures. These materials are an excellent option for use as external reinforcing because of their light weight, resistance to corrosion, and high strength. Externally bonded FRP sheets have been used to increase moment capacity of flexural members and to improve confinement in compression members. Investigations into the use of externally bonded FRP sheets for shear strengthening have also been conducted and have been shown to be viable. The objectives of this study were to review the current research on shear strengthening with FRP …


Optimizing Multiagent, Multi-Injected Swell Modifier, Marshall B. Addison, Thomas M. Petry Jan 1998

Optimizing Multiagent, Multi-Injected Swell Modifier, Marshall B. Addison, Thomas M. Petry

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Interactions of expansive clay soils with transportation facilities have caused billions of dollars of damage. In the process of determining agents and methodologies to overcome expansive clay behavior, multiple injections of chemical agents into the subgrade to modify clay behavior are most promising. A study was conducted to optimize a potassium-rich solution of four parts. The modifying solution has been injected into expansive clay subgrades with success since the early 1970s. A laboratory methodology was developed to inject specimens multiple times and to conduct swell tests. Screening tests were conducted to evaluate linear effects that each of the four constituents …