Development of ESAL Forecasting Procedures for Superpave Pavement Design

This report documents the analysis methods used to develop the Equivalent Single Axle Load (ESAL) forecasting program for Superpave projects. In addition, this report discusses the procedures used in the ESAL forecasting program to forecast ESALs in the design lane for pavement resurfacing/overlay projects which are consistent with the Superpave process of asphaltic mixture design

Edge Drain Performance

Edge drain systems are used on new highway construction projects and rehabilitation projects to reduce the moisture content of the pavement block and subgrade. Maintaining dry conditions in and around these components increases the subgrade strength and extends a pavement’s surface life. Edge drain systems can only operate effectively, however, if the entire subsurface drainage system functions properly. While many studies have demonstrated the benefits of edge drain systems, no comprehensive investigation of their performance has been undertaken in the state of Kentucky in over 20 years. After the Kentucky Transportation Cabinet (KYTC) identified problems with an edge drainage system along a segment of Interstate 275 in Kenton County, the agency commissioned researchers at the Kentucky Transportation Center (KTC) to evaluate the performance of edge drains on roadway segments that will be resurfaced in the coming years. Researchers comprehensively inspected 10 roadway segments, assessing several components of their edge drain systems. For edge drain systems with headwalls, researchers found that all headwalls (n =126) were in good condition and free of structural issues. Roughly 29% of the outfall waterways prevented the flow of water from the headwall, while 65% of the outlet waterways were blocked to some extent by gravel, mud, silt, or other debris, and 61% of the outlet pipes were obstructed. Of the edge drain systems draining to catch basin inserts or ditch bottom inlets (n = 110), outfall waterways were clear on 97% of the systems, but just 14% of the edge drains were unobstructed. Based on inspections, edge drain systems were classified as good, compromised, or undetermined (the final designation being used if conditions prevented a full inspection) and identified a probable failure mode. Approximate 75% of the problems found during inspections were related to maintenance, with the remainder the product of construction activities. To preserve edge drains in a functional condition, post-installation inspections should be conducted, and yearly inspections and cleanings of headwalls and outlet pipes completed. Other methods for outletting water (e.g., dry wells) can also be explored

Full-Depth Reclamation of Asphaltic Concrete Pavements

The Kentucky Transportation Cabinet (KYTC) has used a full-depth reclamation (FDR) process over the past few years to rehabilitate asphalt pavements exhibiting widespread base failures. FDR transforms existing hot-mix asphalt (HMA) pavement and underlying granular materials into a stabilized base layer. The stabilized layer is then overlaid with a new pavement surface layer. Until now, deciding when and how to use the FDR process has not been well specified in Kentucky — the Cabinet has commonly used a Special Note for Cement Stabilized Roadbed as guidance and relied on the contractor for acceptable materials design. Previous research conducted by the Kentucky Transportation Center (KTC) and funded by KYTC proposed guidelines for FDR pavements and considered various binding compounds including, cement, asphalt emulsion, and foamed asphalt. Guidance also included a process for identifying potential projects for the FDR process and recommendations for examining material sampling, testing, mixture design, structural design parameters, and selection requirements for FDR treatment established through preconstruction planning activities. It also addressed quality control and quality assurance. This report builds on those guidelines by providing a special note for the use of the FDR in Kentucky

Forensic Pavement Evaluation for US 31 W, Jefferson County, Kentucky Using Ground Penetrating Radar

The Kentucky Transportation Center (KTC) utilized ground penetrating radar technology to provide a forensic evaluation of the existing pavement structure for the US31W pavement rehabilitation Project in Jefferson County, KY. Processed ground penetrating radar data indicated that the integrity of the underlying concrete pavement beneath the asphalt pavement appears to be competent and structurally sound. The clay soil beneath the concrete pavement appears relatively dry and well compacted. The analyzed GPR data also indicated that the average asphalt layer varied by lane throughout the project from 4.89 to 7.59 inches +/- ½ inch and that the underlying concrete layer average varied by lane throughout the project from 6.59 to 8.12 inches +/- ½ inch. This information was shared with design engineers in efforts to select the most appropriate pavement rehabilitation repair

Evaluations of Wall Structures in Kentucky (KYSPR-85-107)

Approximately 209 retaining wall structures were visually evaluated under this study for long-term performance. The inspection included concrete crib, single-barrel and double-barrel culvert wing, metal bin, Gabion, rigid concrete, Keystone block, tiedback, mechanically stabilized earth (M.S.E.), Tech Wall, and sound walls. Significant structural distress was observed in several of the wall systems. This report discusses the performance of each wall system and makes recommendations on the future use of these systems

Evaluation of Corrugated Steel Pipe Culverts on KY 61, Cumberland County

In February of 1998, the Kentucky Transportation Cabinet requested that the Kentucky Transportation Center investigate three corrugated metal pipe culverts on the relocation project of KY 61. The pipes were installed in June and July of 1997. The embankments over the three pipes were completed In October of 1997. Based on the information that was gathered, it appears that the pipes were manufactured according to specifications. The gage of the pipe is on the lower end of acceptance. The pipes appear to have been well aligned and properly bedded. Some of the dents and buckles in the pipe may have been induced during the early stages of construction. The CL backfill along with the 10 gage pipe should have not been used together. At this time, the deflection monitoring points indicate that the culverts appear to be stable (A vertical change of l-Inch was recorded at Station 226+60. 250 feet from the inlet on April 8. 1997. This reading needs to be verified). It is evident that the clay backfill is the controlling factor at tho time. At the time the soil samples were taken, on the average for all three culverts the degree of saturation was 83 percent. It is uncertain at this time if the soil will become further saturated

Procedures for Determining a Working Capacity for Disadvantaged Business Enterprises (DBE) for Highway Construction and Consulting Projects in Kentucky

This report documents the working capacity of the Disadvantaged Business Enterprise (DBE) community performing on federal aid highway projects over the last four federal fiscal years 1995- 98. This includes the work performed by Minority Business Enterprises (MBE), Minority Women Business Enterprises (MWBE) , and Women Business Enterprises (WBE) construction firms serving both as a prime contractors and subcontractors. The work of DBE design consultants was not included as part of this study. The impact of five DBE firms who should be graduating from the program is also discussed. In addition several different scenarios are discussed relating to the adjustment of the current DBE federal goal, and to identify if the DBE community will be able to perform the adjusted volume of work in fiscal year 2000 if the current goal is reduced

Evaluation of Working Capacity for Disadvantaged Business Enterprises (DBE) For Highway Construction in Kentucky, FY 2004 Update

The Kentucky Transportation Center gathered the appropriate information, performed a series of computations and analyses, prepared the attached documentation, and makes the following recommendations to the Kentucky Transportation Cabinet for their DBE goal for Federal Fiscal year 2004 (October 1, 2003 - September 30, 2004). KTC recommends an overall DBE goal of 9.26%, of which 1.931% is anticipated to be satisfied by race/gender neutral prime contracts, and the resultant 7.33% should established as race/gender conscious subcontracts. The overall DBE goal figures stated here addresses an adjustment of 1.326% for the positive historical goal variance observed for the past eight years

Economic Impact of Heavy Loads On the Highway Infrastructure

During the 1986 General Assembly the Extended-Weight Coal Haul Road System was created by the Kentucky State Legislature. This system was defined to include those highways where more than 50,000 tons of coal had been hauled during the previous year. Trucks hauling coal on the extended-weight system were authorized to exceed the normal weights limits through the payment of an annual decal fee. In efforts to identify the benefactors of the extended coal haul system legislation, this study has been conducted to identify the overall economic impact of hauling heavier total gross weights by coal truck on the highway infrastructure in Kentucky in 1996. In order to identify the overall economic impact of hauling heavier weights by coal truck an economic analysis had to be preformed. This economic analysis compared the monetary benefits achieved by all users for hauling heavier weights by coal truck to the additional expenses incurred by allowing heavier weights to be hauled on the highway infrastructure

Evaluation of Edge Drains on Interstate 64 Fayette, Scott, and Woodford Counties

This report documents findings of the investigation of edge drains and their associated outlets on Interstate 64 from Milepost 65 to Milepost 75.6 in Fayette, Scott, and Woodford Counties. The study was initiated due to significant amounts of water and fines coming up through the AC surface. State and Federal Officials were concerned that possible failures in the edge drains were causing pumping and staining which will ultimately lead to premature pavement failure. Several factors appear to be contributing to the staining and pumping at the surface. These factors are discussed in the report