Pavement Underdrain to Achieve Longer Life Pavement Structure

Drainage as the key to pavement performance has been suggested since the early design of modern pavement structures. In fact, the three parameters for pavement performance are drainage, drainage and drainage. Drainage is so important to the performance of pavement that many state DOTs mandate a pavement underdrain system for routes with medium to high truck traffic. In the current evolution of pavement underdrain design, the speed of water removal from the soil foundation is the key issue. In a recent field investigation, some pavement sections with an underdrain system are not immune to pavement structural deterioration. It was determined that proper construction of the underdrain system is the key to ensuring that water will not accumulate in the soil foundation. This presentation will explore the requirements, design, construction, and performance of the underdrain system

Correlation between Resilient Modulus (M\u3csub\u3eR\u3c/sub\u3e) of Soil, Light Weight Deflectometer (LWD), and Falling Weight Deflectometer (FWD)

INDOT adopted the Mechanistic-Empirical Pavement Design Guide (MEPDG) beginning January 1, 2009, which is based on the FHWA Long Term Pavement Performance (LTTP) field study. The resilient modulus of the soil, MR, is required to implement the new design guide, as well as the pavement input parameters. The soil resilient modulus test requires special, expensive, equipment, significant time investment and effort, which has led researchers to develop MR prediction models and alternative methods to estimate the resilient modulus using non-destructive tests such as Falling Weight Deflectometer, FWD, Light Weight Deflectometer, LWD, and Dynamic Cone Penetrometer, DCP. The objectives of the project are geared toward a practical approach for pavement design procedures to effectively determine the soil resilient modulus for rehabilitation projects, targeting specifically untreated subgrade soils type A-6 and A-7-6. A total of four sites in Indiana were selected to conduct FWD, LWD, and DCP tests, as well as resilient modulus tests in the laboratory. In addition to the output from the four sites, additional data were collected from the data repository of INDOT which has geotechnical and pavement information. Extensive analysis and comparisons were done in an attempt at establishing relationships between the field tests and the laboratory results. The study showed the following: (1) high quality FWD tests conducted on top of the pavement can be used to estimate the subgrade MR, as long as site conditions and pavement layers thickness are well known; (2) the results of FWD tests on top of the subgrade are not reliable, as they are affected by the low confinement of the soils; and (3) LWD and DCP tests can be used to provide and assessment of the quality and uniformity of the subgrade, but do not provide reliable estimates of the stiffness of the subgrade

Structural Evaluation of Full-Depth Flexible Pavement Using APT

The fundamentals of rutting behavior for thin full-depth flexible pavements (i.e., asphalt thickness less than 12 inches) are investigated in this study. The scope incorporates an experimental study using full-scale Accelerated Pavement Tests (APTs) to monitor the evolution of each pavement structural layer\u27s transverse profiles. The findings were then employed to verify the local rutting model coefficients used in the current pavement design method, the Mechanistic-Empirical Pavement Design Guide (MEPDG). Four APT sections were constructed using two thin typical pavement structures (seven-and ten-inches thick) and two types of surface course material (dense-graded and SMA). A mid-depth rut monitoring and automated laser profile systems were designed to reconstruct the transverse profiles at each pavement layer interface throughout the process of accelerated pavement deterioration that is produced during the APT. The contributions of each pavement structural layer to rutting and the evolution of layer deformation were derived. This study found that the permanent deformation within full-depth asphalt concrete significantly depends upon the pavement thickness. However, once the pavement reaches sufficient thickness (more than 12.5 inches), increasing the thickness does not significantly affect the permanent deformation. Additionally, for thin full-depth asphalt pavements with a dense-graded Hot Mix Asphalt (HMA) surface course, most pavement rutting is caused by the deformation of the asphalt concrete, with about half the rutting amount observed within the top four inches of the pavement layers. However, for thin full-depth asphalt pavements with an SMA surface course, most pavement rutting comes from the closet sublayer to the surface, i.e., the intermediate layer. The accuracy of the MEPDG’s prediction models for thin full-depth asphalt pavement was evaluated using some statistical parameters, including bias, the sum of squared error, and the standard error of estimates between the predicted and actual measurements. Based on the statistical analysis (at the 95% confidence level), no significant difference was found between the version 2.3-predicted and measured rutting of total asphalt concrete layer and subgrade for thick and thin pavements

SR25 Roller-Compacted Paving Shoulder Case

This presentation will discuss roller-compacted concrete (RCC) paving, one of the Midwest’s most sought-after paving alternatives. A case study/ video presentation of the 2013 SR 25 project will be followed by a panel discussion of RCC experts from IMI Concrete, E&B Paving, IRMCA, and INDOT, who will offer insight and guidance about materials, testing, paving/construction techniques, best practices, benefits, and other aspects of this pavement option

Evaluation of Zero Velocity Deicer Spreader and Salt Spreader

Increasing traffic volumes and declining resources have led to a need for innovative winter maintenance strategies, techniques, equipment and materials while not sacrificing the safety of the traveling public. Any reduction of salt usage will ease fund for other maintenance operations while minimizing salt runoff on surface and ground waters and effect of road salt on roadside vegetation. In the past, conventional spreaders have been designed for sand and are generally incapable of metering the lower, more precise amount of salt desired. The use of materials in solid form demands critical timing of the application to minimize loss of the material by being blown off the road by traffic, especially by high speed and commercial vehicles. Further loss of a straight solid salt can occur during application with conventional spreaders because of the particles bouncing off the pavement. Advancements in the design of zero velocity spreaders have enabled the placement of solid chemicals on the pavement with minimum bounce. The basic principle of the zero velocity spreader is rather simple. The zero velocity spreader ejects salt particles at zero velocity relative to the roadway. With this principle, salt particles are “placed” to the intended area on the roadway and a lot less to the area outside the roadway. Based on the tests, the Zero Velocity Systems will give excellent performance with a large number of cost savings due to the accurate placement of salt particles on the roadway. However, on the slower truck speed, a modified system such as the Y system or Muncie system, can give a satisfactory result as well

High Performance Concrete Pavement in Indiana

Until the early 1990s, curling and warping of Portland cement concrete pavement did not concern pavement engineers in many transportation agencies. Since beginning construction of the interstate system in the United States in the late 1950s through the late 1980s, the performance of Portland cement concrete pavement has been associated with properties of concrete as a pavement material. In those years developed standards and design guidelines emphasized better concrete materials and construction control. At the time, combining curling and loading stresses was quite controversial due to the nature of the load-carrying capacity of concrete pavement and the occurrence of types of loads. Arguments developed that the types of loads (traffic and curling) rarely occurred at the same time of day. The concrete pavement design principle did not include the effects of curling and warping of concrete pavement as determining design factors in pavement performance. This research project was initiated as a response from the INDOT Pavement Steering Committee related to the joint spacing of Jointed Plain Concrete Pavement in Indiana. There was an initiative in the Committee to reduce the joint spacing from 18 feet to 15 feet as a way to reduce premature concrete pavement deterioration. There was an indication that some newly paved JPCP had transverse cracks even before the pavement section was opened to traffic. In this experimental study, several important conclusions were drawn from temperature analysis, stress-strain analysis, and other data analysis. The analysis from this experimental study supports the decision by INDOT to shorten the concrete pavement joint spacing to increase the performance of Jointed Plain Concrete Pavement in Indiana

I-65 South Split Continuously Reinforced Concrete Pavement

Continuously reinforced concrete pavement (CRCP) is constructed with reinforcing steel placed in along the entire length of the pavement. CRCP forms tight transverse cracks to evenly transfer loads without the need of contraction joints. The result is a continuous, smooth-riding pavement surface capable of accommodating heavy traffic loads in a severe environmental condition. First constructed in Indiana more than 75 years ago on US-50, CRCP became popular with the construction of the Interstate Highway system in the 1960s and 1970s. Many sections of interstate and non-interstate highways constructed at that time are still in service today, having outperformed their original design-life predictions. After more than 30 years’ absence from Indiana pavement construction, the CRCP is making a successful comeback in the interstate pavement. This presentation will discuss the design principle and construction of the newest CRCP pavement in Indiana on I-65 South Split

Best Practices for Bridge Deck Overlays

This presentation discusses recent research regarding alternative bridge deck overlay methods and best practices associated with their use

Pavement Rehabilitation Options in Indiana for INDOT

Many pavement rehabilitation options are now available to maintain the function and structure of a pavement section, and pavement engineers can choose an option that is suitable for the existing pavement condition. Many agencies today use traditional pavement rehabilitation techniques such as patching, overlay, and mill and fill. Recent developments in materials and construction have made available new rehabilitation options that are not only cost effective but also increase the use of recycled materials. This presentation will feature hot-in-place recycling, cold-in-place recycling, and full-depth reclamation techniques used successfully with recently rehabilitated pavement sections in Indiana