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Articles 2581 - 2610 of 2858
Full-Text Articles in Engineering
Accident And Economic Analyses Of Access Control On Several Bypasses, Kenneth R. Agent
Accident And Economic Analyses Of Access Control On Several Bypasses, Kenneth R. Agent
Kentucky Transportation Center Research Report
In an effort to relieve congestion on urban streets, bypasses have been built to provide through traffic a route by which the downtown areas can be avoided.
In many cases, though, bypasses have created a serious accident potential because they were built with at-grade intersections and no access control. This leads to commercial developments along the bypass and congestion at major intersections. Bypasses were constructed in this manner because of the high initial cost involved in building a bypass with access control and grade-separated interchanges. There is, therefore, a need to determine if the accident cost savings, along with time …
Application Of Gravity And Intervening Opportunities Models To Recreational Travel In Kentucky, Kenneth D. Kaltenbach
Application Of Gravity And Intervening Opportunities Models To Recreational Travel In Kentucky, Kenneth D. Kaltenbach
Kentucky Transportation Center Research Report
Weekend outdoor recreational travel has a major impact on the highway network in Kentucky. Data from a previous study (1) indicate that the number of people visiting 42 typical Kentucky outdoor recreation areas on an average summer Sunday in 1970 was approximately 260,000. Most of these 42 areas, by virtue of their outdoor nature, are located in rural settings. Most have access to major arterial highways only by means of narrow, low standard rural roads. Traffic generated by the recreation areas and their associated developments severely strains these secondary access highways and places a significant additional load on the rural …
Unstable Embankment: Us 119 Harlan-Pineville Road Stations 1260 To 1265, Tommy C. Hopkins
Unstable Embankment: Us 119 Harlan-Pineville Road Stations 1260 To 1265, Tommy C. Hopkins
Kentucky Transportation Center Research Report
In January I972, an in-depth investigation of an unstable embankment, Figure 1, on US 119 near Station 1262+00 was initiated. The site is approximately five miles southwest of Harlan and near Wilhoit. Figures 2 and 3 show a plan view and a typical cross-section, respectively. US 119 travels on a tangent from Station 1252+16 to 1255+54 in a northerly direction. From that point, the roadway gradually curves four degrees to the east, becoming tangent again near Station 1275+00. At about Station 1258+00, the roadway emerges from a cut, and near Station 1266+00 it reenters a small cut. Between the latter …
Skid Resistance Of Pavements [July 1972], Rolands L. Rizenbergs, James L. Burchett, Cass T. Napier
Skid Resistance Of Pavements [July 1972], Rolands L. Rizenbergs, James L. Burchett, Cass T. Napier
Kentucky Transportation Center Research Report
Standard pavement types and experimental surfaces on roads throughout Kentucky were evaluated in terms of skid resistance and effects of traffic, wear, and polishing. Friction-vs-speed gradients and the relationships between locked-wheel and incipient friction were determined. Class I bituminous pavements on high-speed, four-lane roads were found to be significantly more skid resistant than on two-lane highways and somewhat more skid resistant than concrete surfaces (especially those containing calcareous gravel aggregates). Sand-asphalt surfaces containing significant proportions of limestone sands showed inadequate level of friction for the traffic sustained. Several experimental sand asphalts without limestone sands exhibited greater skid resistance; Kentucky rock …
High-Intensity Reflective Materials For Signs, Rolands L. Rizenbergs
High-Intensity Reflective Materials For Signs, Rolands L. Rizenbergs
Kentucky Transportation Center Research Report
The intuitive need for improved sign legibility has increased through the years as traffic volumes, speeds and roadway designs have advanced. Because of increased traffic volumes, low-beam headlight illumination at night has become more imperative. Signs are being located farther from the travelled lanes; higher speeds are requiring messages to be more legible at greater distances (for driver decision and response). Recent studies have indicated that even Engineering Grade (2200 and 3200 Series) Scotchlite or materials designated as Type I, Class A in S.P. No. 89-A, may be inadequate for some signing situations. Signs may be made larger and(or) incorporate …
Proposed Remedies: Unstable Embankment At Mile Post 188 And Channel Erosion At Mile Post 190-191; I 64, Boyd County, David R. Houchin, James H. Havens
Proposed Remedies: Unstable Embankment At Mile Post 188 And Channel Erosion At Mile Post 190-191; I 64, Boyd County, David R. Houchin, James H. Havens
Kentucky Transportation Center Research Report
The Department became aware of fill slippage on I 64 some 300 feet east of mile post 188 during the summer of 1967. In September of that year Mr. L. E. Richardson, Division of Maintenance, and Mr. Gordon D. Scott, Division of Research, made an inspection of the area. Mr. Scott reported cracking of shoulder, movement of the guard rail, and a failure in the berm along the toe. However, subsequent inspections showed the slip to be stabilizing by itself until late in 1970 when some additional movement was observed. In January of 1971, the most conspicuous pavement failure was …
Expansive Limestone Aggregate In A Concrete Pavement, James H. Havens, Assaf S. Rahal
Expansive Limestone Aggregate In A Concrete Pavement, James H. Havens, Assaf S. Rahal
Kentucky Transportation Center Research Report
Recurrent blowups and surface cracking are common symptoms of distress in concrete pavements. Premature appearance of distress symptoms is alarming because the materials used in the concrete become suspect. Criteria for design, quality of materials, and construction are necessarily re-evaluated. Indeed, a dutiful effort to discover the cause(s) and to provide future safeguards is reasonably expected.
The analysis of causative factors besetting I 65-1(13)13 was complicated by an intuitive notion that blowups and surface cracks might be separate and independent problems. The crack pattern resembled the configuration of the wire mesh -- which was vibrated into position after the concrete …
An Operational Analysis Of The I 64, I 65, I 71 Route Junction In Louisville, Jerry G. Pigman, William M. Seymour, Kenneth R. Agent, Don L. Cornette
An Operational Analysis Of The I 64, I 65, I 71 Route Junction In Louisville, Jerry G. Pigman, William M. Seymour, Kenneth R. Agent, Don L. Cornette
Kentucky Transportation Center Research Report
The Kennedy Interchange in Louisville is the most geometrically complicated of any in Kentucky; it is the junction of three interstate routes, I 64, I 65, and I 71. The many diverging, weaving, and merging movements demand a driver's attention. One merging situation collapses into an impasse during peak-hour traffic. This study is responsive to certain inquiries by the Department concerning safety and possible discovery of design deficiencies at this interchange. It was not intended to be an in-depth study but rather an exploratory identification of problems and their locations; more comprehensive studies, by others, would ensue if needed. The …
Comparative Evaluation Of Raygo 404 Vibratory Roller, Jerry D. Ross, Herbert F. Southgate, Donald C. Newberry Jr.
Comparative Evaluation Of Raygo 404 Vibratory Roller, Jerry D. Ross, Herbert F. Southgate, Donald C. Newberry Jr.
Kentucky Transportation Center Research Report
Roller evaluations are rather phenomenological -- that is, one must rely somewhat on observations. Density measurements following each excursion of the compactor may not relate directly to the work done in compressing the layer. When no increase in density is realized, no work is accomplished. Work is defined here in the classical sense. Energy expended without producing an increase in density is wasted. Thereafter, the only way additional classical work can be done on the layer is to reduce density.
The number of excursions necessary to achieve an acceptable or comparable density generally reflects efficiency of the compactor. Much may …
Noise Pollution And Abatement: A Review Of Literature, Kenneth R. Agent, Robert C. Deen
Noise Pollution And Abatement: A Review Of Literature, Kenneth R. Agent, Robert C. Deen
Kentucky Transportation Center Research Report
Complaints concerning traffic noise and possibly seismic vibrations emanating from highways would probably have been adjudicated on the basis of common law doctrines pertaining to "nuisances", "common enemy'', and ''power of relief" were it not for recent legislation and regulations directed toward protection of the total environment. In effect, "freedom from noise" has been added to the clean water, clean air, clean earth policies. Surely each of those policies are founded on public sentiment.
There have been a few instances where the Department has yielded relief because of traffic noise. Now safeguarding regulations seem inevitable.
In the past, this Division …
Stress Histories Of Bridge Members From Scratch Gage Records, Ronald D. Hughes
Stress Histories Of Bridge Members From Scratch Gage Records, Ronald D. Hughes
Kentucky Transportation Center Research Report
This report describes the use of scratch gages for obtaining strain histories of bridge members. Basic components of the gage are designated and its operation is described in general terms. Stress histories, deduced from strain records, for various members of three bridges obtained through use of the gages are presented. A procedure for use in replicating sections of deteriorated members is described.
Bridges: Synthesis Of Load Histories And Analysis Of Fatigue, James H. Havens, Robert C. Deen
Bridges: Synthesis Of Load Histories And Analysis Of Fatigue, James H. Havens, Robert C. Deen
Kentucky Transportation Center Research Report
Repeated stressing of metals above certain limits induces inter- and intra-crystalline dislocations and cleavages and eventually cracks which propagate to failure. Some authorities consider crack propagation to be a separate and discrete stage in the failure process. The internal damage is insidiously cumulative and irreversible. This phenomenon was recognized as early as 1829 and was termed fatigue as early as 1839(1). From the beginning of fatigue testing (Wohler, 1858-1870), results have been reported as S-N, S-log N, or log S-log N curves, where N is the number of repetitions of stress S. From a structural design point of view, …
Chronological Listing Of Research Reports, Division Of Research, Kentucky Department Of Highways
Chronological Listing Of Research Reports, Division Of Research, Kentucky Department Of Highways
Kentucky Transportation Center Research Report
No abstract provided.
Experimental Overlay Of Glazon Over Two Bridge Decks, Assaf S. Rahal, A. B. Blankenship
Experimental Overlay Of Glazon Over Two Bridge Decks, Assaf S. Rahal, A. B. Blankenship
Kentucky Transportation Center Research Report
In accordance with a Personal Service Agreement entered into with the Glazon Industries, Inc., on July 2, 1971, the two subject decks were patched and overlayed with Glazon. On July 27, 1971, work started on RP 106-286-HG3, KY 395 bridge over I 64 in Shelby County. Work consisted of routing old concrete and sandblasting the surface (Figures 1 and 2). State personnel and equipment were used for all cleaning operations. The same procedures were followed to clean HM 99-1324A-MB3 in Powell County near Clay City.
On July 28, 1971, Glazon personnel and equipment arrived at the work site in Shelby …
Subject Listing Of Research Reports, Division Of Research, Kentucky Department Of Highways
Subject Listing Of Research Reports, Division Of Research, Kentucky Department Of Highways
Kentucky Transportation Center Research Report
No abstract provided.
Summary Of Pavement Surface Texture Measurement Methods, Jerry G. Rose
Summary Of Pavement Surface Texture Measurement Methods, Jerry G. Rose
Kentucky Transportation Center Research Report
This tabular summary represents an expanded version of a draft prepared under the direction of Prof. Bob M. Gallaway of Texas A & M University. The table was compiled from a literature survey conducted during spring 1970. A survey of all states and agencies engaged in quantitative measurements of surface texture would be helpful for updating and finalizing the table. In the meantime, any comments or suggestions concerning any of the tabular entries or other methods of surface texture measurement should be addressed to Dr. J. G. Rose, Research Engineer, Division of Research, Kentucky Department of Highways, 533 South Limestone, …
Relationship Between Soil Support Value And Kentucky Cbr, Tommy C. Hopkins
Relationship Between Soil Support Value And Kentucky Cbr, Tommy C. Hopkins
Kentucky Transportation Center Research Report
Three slightly different correlations between Kentucky CBR's and the AASHO Road Test soil support values were developed. The first relationship was made by assuming a logarithmic scale between Kentucky CBR's of 5.2 and 100, which corresponded to values on the soil support scale of 3 and 10, respectively. The Kentucky CBR of 5.2 was determined by performing tests on the AASHO road subgrade soils. For practical purposes, the AASHO Road Test crushed stone base material was assumed to be a "100 percent CBR material" (this assumption was based on CBR data previously reported by Shook and Fang). The second correlation …
Statistical Quality Control Of Highway Construction And Materials, J. B. Venable
Statistical Quality Control Of Highway Construction And Materials, J. B. Venable
Kentucky Transportation Center Research Report
The objective of this report is to review existing local practices used in establishing and enforcing highway specifications and construction processes and to compare these practices. With procedures based on statistical quality control concepts. In order that statistical quality control concepts may be properly used where applicable, the first part of this report considers the general theory underlying the use of statistical control methods and the development of different types. Of acceptance plans which may be used in the highway construction industry. The second portion of the report is concerned with analyzing and comparing Kentucky's current specification requirements with typical …
Continuously Reinforced Concrete Pavement, James H. Havens
Continuously Reinforced Concrete Pavement, James H. Havens
Kentucky Transportation Center Research Report
A sampling-type crack survey was made in July 1969; 200 feet in each 1000 feet were sampled. The average interval between cracks was 5.78 feet. Paving was completed in late 1968. The average crack interval in July 1970 was 4.14 feet. The 1970 survey was also a sampling type.
It is apparent that cracking approached maturity or equilibrium during the first year. Apparently, too, most of the cracking occurred during the first few weeks after construction – which suggests curing shrinkage as a contributory cause. A discussion of the significance of time and temperature will follow the presentation of other …
Evaluation Of Cored Specimens From Timber Caisson Beneath Pier No. 2 Of The Us 25 Bridge Over The Ohio River Between Covington And Cincinnati, James H. Havens, Assaf S. Rahal
Evaluation Of Cored Specimens From Timber Caisson Beneath Pier No. 2 Of The Us 25 Bridge Over The Ohio River Between Covington And Cincinnati, James H. Havens, Assaf S. Rahal
Kentucky Transportation Center Research Report
Pier No. 2 of the former C&O Bridge at Covington is off-shore from the Kentucky side of the Ohio River. It was built in 1887. In 1927, this pier was extended downstream to support a new railroad bridge. The other three piers remained independent. The original structure was then converted to highway use and was purchased by the Commonwealth of Kentucky in 1937. In 1968, an engineering analysis of the superstructure indicated critical deficiencies in terms of "safety factors", and the bridge was closed to all traffic. Subsequently, various plans for reconstruction came under consideration. Of greatest significance here is …
Development Of Specifications For Reflex-Reflective Materials, Ronalds L. Rizenbergs
Development Of Specifications For Reflex-Reflective Materials, Ronalds L. Rizenbergs
Kentucky Transportation Center Research Report
Evolutionary changes in highway design, automobiles and retro-reflective products prompted Kentucky to undertake a study to update specification requirements for signing materials, delineators and coating compounds. The study was primarily concerned with geometric relationships between the driver, headlamps and traffic signs; investigation of reflectivity, color, durability and other properties of available reflective materials; adoption of testing apparatus to measure material properties; and development of test procedures.
A review of specific sign viewing conditions on the road indicated the appropriateness of reflectivity testing at 0.5-degrees and 0.2-degrees angles of divergence. These angles, however, limit examination of materials at viewing distances in …
Experimental Sand-Asphalt Surface, Robert L. Florence, Herbert F. Southgate
Experimental Sand-Asphalt Surface, Robert L. Florence, Herbert F. Southgate
Kentucky Transportation Center Research Report
Wearing surfaces of Kentucky rock asphalt applied in thin layers were used extensively in Kentucky for many years. Sand asphalts, which generically include rock asphalt, are now a reemergent generation of surfacings to be investigated (1,2,3). An interim report (4) related the construction and interim performance of trial surfacings in Logan County. Two bridge deck sand-asphalt surfacings have been reported (5). This report covers sand-asphalt construction and performance since 1966. Pertinent project data and comments are contained in Appendix A. The several Special Provisions are included in Appendix B.
Interest in sand-asphalt wearing surfaces issues from the skid-resistant qualities which …
Replication Of Eye-Bars And Measurement Of Losses In Cross Section Due To Corrosion, Assaf S. Rahal, J. R. Philpot
Replication Of Eye-Bars And Measurement Of Losses In Cross Section Due To Corrosion, Assaf S. Rahal, J. R. Philpot
Kentucky Transportation Center Research Report
Recent availability of high pressure water blasters made it possible to remove rust accumulated between the eye-bars near pin connections on the Central Bridge (Figure 1) over the Ohio River at Newport. Previously, they had never been thoroughly cleaned. Cleaning of two connections on a trial basis enabled an inspection between the bars. It was apparent then that the deterioration was critical enough to necessitate examination of the several bar groups and to accurately measure their least cross sections.
The Research Division undertook the task of replicating and measuring the bars. Figures 2 and 3 show one set of bars …
A Study Of The Secant Law For Sporadic E, Ruey-Yuan Han
A Study Of The Secant Law For Sporadic E, Ruey-Yuan Han
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The secant law is the relationship between the frequencies of a vertically incident wave and an obliquely incident wave that are reflected from the same level (i.e., density) of a stratified ionosphere. This thesis investigates the validity of the secant law applied to sporadic E.
Sporadic E data from two backscatter sounders and one vertical incidence ionosonde located in Japan were studied to test the validity of the secant law. The B-scan photos of the backscatter sounders were searched for Es patches which were then compared with the sporadic E parameters defined for vertical incidence ionograms.
Finally, two theoretical …
Median Design And Accident Histories, Gordon R. Garner
Median Design And Accident Histories, Gordon R. Garner
Kentucky Transportation Center Research Report
The purpose of this study was to provide information concerning the accident histories of various median types to verify minimum requirements for width and cross section. Previous accident studies failed to disclose significant relationships between median width and accident rates. Those studies did not recognize or control several important variables that were controlled in the present study. The efforts here are to compare median types on rural, four-lane, fully controlled access facilities with similar geometries other than median types. An attempt was made to account for some of the Variability in the accident data. Thus, this study gives information on …
Legal Aspects And Guidelines Pertaining To Drainage Of Surface Waters, D. W. Mclellan Jr., Victor Fox
Legal Aspects And Guidelines Pertaining To Drainage Of Surface Waters, D. W. Mclellan Jr., Victor Fox
Kentucky Transportation Center Research Report
A previous study ("Research Relating to State Highway Laws", reported January 1967) afforded us an opportunity to review a vast array of literature and statutory law pertaining to enabling legislation and administrative authority to construct and maintain highways. It was surprising to find that the statutes are void of guidance on certain subjects: there are great "bodies" of unwritten or non-statutory laws which are referred to as "common law" and "civil law", which are deeply rooted in the past; many are doctrinal or equitable; many are extraordinary and argumentative -- they should not be confused with Civil Procedure. They have …
Pavement Slipperiness Studies, James L. Burchett Jr., Ronalds L. Rizenbergs
Pavement Slipperiness Studies, James L. Burchett Jr., Ronalds L. Rizenbergs
Kentucky Transportation Center Research Report
Studies of pavement skid resistance in Kentucky have been in progress since 1956. In 1964, an extensive investigation into the use of an automobile as a testing tool was undertaken and an interim standard method of test was selected. Since then, investigations with the device have continued, both to facilitate meaningful interpretation of skid-test data and to evaluate the skid resistance performance of pavement surfaces.
Variables associated with the testing device, procedures and pavement surfaces were investigated. Several paving projects were tested to determine the number of sites required to obtain a representative result. It was found that on most …
Slurry Seal Maintenance Applications, Robert L. Florence, Herbert F. Southgate
Slurry Seal Maintenance Applications, Robert L. Florence, Herbert F. Southgate
Kentucky Transportation Center Research Report
A slurry seal mixture consists of graded fine aggregate (normally minus 3/8-inch material), mixing grade emulsified asphalt (SS-1 or SS-lH), and water. The water is added to aid in mixing and to provide a free-flowing consistency so that the mixture can be spread in thin layers on the surface of an existing pavement. After the mixture is spread, the water evaporates and the remaining material, aggregate and base asphalt, forms a thin seal on the pavement surface which resembles a fine-grained asphaltic-concrete surface. As a result of the free-flowing consistency and the fineness of the aggregate, a slurry mixture readily …
Final Performance Report On Experimental Use Of Thermoplastic Pavement-Striping Materials, Assaf S. Rahal, Ronald D. Hughes
Final Performance Report On Experimental Use Of Thermoplastic Pavement-Striping Materials, Assaf S. Rahal, Ronald D. Hughes
Kentucky Transportation Center Research Report
This study was undertaken in order to: 1) evaluate the performance of thermoplastic striping materials, 2) compare their performance on both portland cement concrete and bituminous concrete pavements to that of conventional traffic paints, and 3) to evaluate the economics of thermoplastics in terms of cost per mile per day of useful life. The performance of two brands of thermoplastic striping materials and conventional traffic paints applied at nine test sites in both rural and urban areas is reported herein. Application procedures, site locations, repair histories and materials specifications are included. Accumulative costs for each material at all sites for …
Freeze-And-Thaw Phenomena In Concretes And Aggregates, James H. Havens
Freeze-And-Thaw Phenomena In Concretes And Aggregates, James H. Havens
Kentucky Transportation Center Research Report
This report summarizes several years of research relating to damage to concrete and aggregates undergoing freezing and thawing. Basic principles involving freezing and attendant pressures are considered. Application of these principles to the evaluation of concrete was accomplished in experiments on concrete having low and high air contents. The effects of air entrainment upon freeze-thaw resistance were demonstrated.
Freeze-thaw characteristics of saturated aggregates relative to their physical properties such as porosity, absorption and bulk specific gravity were studied by submerging individual particles in pre-chilled mercury. Pressures associated with popouts in concrete were monitored and are presented along with accompanying theoretical …