Meeting local needs for training, technical assistance, and research in transportation

FY-2017 and FY-2016 Research Projects are listed below:
 
More on KU Transportation Research
To view prior KDOT-funded KU transportation research projects, go to the KDOT Research Library link below to generate a list of reports or search for a particular topic or report.

 

2017 KU Transportation Center Projects

 
Principal Investigator/Co-Principal Investigator Project Description
Han, Jie/Parsons, Robert
KDOT has installed a large number of corrugated steel pipes in transportation projects for decades.  With time, steel rusts and some of these steel pipes have corroded badly, resulting in structural section loss and water leakage.  The structural section loss is expected to reduce the load-carrying capacity of the pipe and increase its deformation under a load.  In other words, the serviceability of the corroded pipe is degraded.  Water leakage erodes soil below and around the pipe, resulting in not only ground settlement but also loss of subgrade support for the pipe.  The loss of subgrade support further reduces the serviceability of the corroded pipe.  HDPE liner pipes have been used inside corroded pipes to improve hydraulic capacities and prevent further soil erosion around the corroded pipes.  Grout has been used to fill the space between the corroded pipe and the liner pipe and voids around the corroded pipe.  However, grouting is often done under pressure, which will apply loads on the corroded pipe and the liner pipe.  Corroded pipes and HDPE liner pipes have limited structural capacities and they may deform and collapse under excessive grouting pressure.  In addition, grouting may induce a peaking effect of the pipe, which results in higher stresses on top of the pipe crown.In this research, three full-scale box tests will be performed at the University of Kansas to evaluate grouting effects on lined, corroded steel pipes buried in soil, including one pipe fully-corroded at the bottom with subgrade support, one fully-corroded pipe at the bottom with loss of subgrade support, and one fully-corroded pipe at bottom with voids around the pipe.  The large test box (10 ft x 7 ft x 7 ft high) has been successfully used to test steel-reinforced HDPE pipes buried in soil for a previous K-TRAN project.  Thisresearch is expected to assess the grouting effects on deformations of corroded steel pipes and HDPE liner pipes and stresses around corroded pipes.      
Parsons, Robert/Han, Jie
KDOT has used lime treatment for subgrade improvement for many years with generally good performance.  However, lime is an expensive additive which requires an extensive cure period.  Contractors have pushed for permission to use lime kiln dust (LKD) as a value engineering substitute.  Lime kiln dust is composed of 55-80% calcium oxide1. It is known to improve soil properties and has been used on a small scale for a number of years, particularly in combination with fly ash, however research to quantify the benefits has been limited and more research is needed. The objective of the proposed research is to investigate the benefits of LKD for stabilization in comparison with lime.  Four soils for which lime is scheduled to be used will be selected.  Samples will be prepared in the lab with both lime and LKD and tested for strength, rate of strength gain, durability (soaking), and control of swelling potential.  KU will also visit up to three test sections constructed during the project and monitor construction practice and measure the strength by DCP and stiffness by LWD of the compacted stabilized subgrade. KU will use the DCP and LWD results to develop correlations between field measurements and the unconfined compression strength of lab samples for use in design and quality assurance. 

Kondyli, Alexandra/Schrock, Steven

Highway agencies are tasked with collecting accurate and reliable traffic data to operate their roadway network and plan for future growth. Due to the varied types of data collection systems (hand counts/in-pavement sensors/roadside sensors), there is some question about the accuracy (and therefore usefulness) of the data that are collected.  Currently, the Kansas Department of Transportation (KDOT) is facing with the issue that the data collected through the existing sensors (Wavetronix) are not considered accurate relative to other methods. Therefore, although the vehicle detection infrastructure is in place, it is not possible to obtain reliable information on traffic flows to be used for planning applications. As such, KDOT oftentimes resolves to outsourcing data collection efforts. The goal of this research is to improve the accuracy of the Wavetronix data that KC Scout and the Wichita Traffic Operations Center collect, and expand the application possibilities of these data.  The primary objective of the proposed project is to reconcile traffic data collected through the Kansas’ traffic management systems with field measured data in order to improve the accuracy of the measurements. This research will essentially provide a calibration process in order for the Scout data and the data collected through the Wichita Traffic Operations Center to meet KDOT’s requirements. 

Han, Jie/Parsons, Robert

For Portland Cement Concrete Pavements (PCCP) in small communities or areas, granular bases, such as AB-3 aggregate, have been used on natural subgrade instead of cement-treated base and lime-treated subgrade.  In addition, reclaimed asphalt pavement (RAP) aggregate and recycled concrete pavement (RCP) aggregate have been increasingly used as a base course material for roadway construction.  To minimize intermixing between aggregate and subgrade soil and lateral spreading of granular base under traffic loading, geosynthetics, such as nonwoven geotextile, woven geotextile, and geogrid, have been used.  However, the performance of granular bases (AB-3, RAP, and RCP) and the benefits of geosynthetics under PCCP have not been evaluated well and a comprehensive study is warranted. This three-phase research project will examine granular base options for PCCP.  The first phase is focused on a large box study, in which cyclic plate loading tests will be conducted on PCCP with different granular base options at the University of Kansas (KU).  The different granular base options will be evaluated and their performances will be ranked based on this study.  The highly ranked granular base options will be evaluated at Kansas State University (KSU) using the accelerated pavement testing facility in the second phase.  Based on the research results from the KU and KSU studies, a field study will be performed jointly by KU and KSU in the third phase of this project.  This research only focuses on the first phase study, i.e., the large box study on granular base options for PCCP.
   

 

2016 KU Transportation Projects

Principal Investigator Project Description
Bennett KDOT currently has approximately 450 aluminum sign trusses that support signage over active highways, and all of these structures utilize an identical coupler connection between the truss and the end support columns.  Notably, aluminum structures cannot reach an infinite fatigue life as steel structures can, which carries the weighty implication that at some point all of these structures will experience fatigue failures.  When the standard KDOT coupler connection was designed in the early 1970s , ultimate strength – not fatigue – was the design criterion.  A project is proposed in which a series of physical fatigue tests are performed to establish the fatigue resistance of the coupler connections.  The fatigue tests are augmented by 3D finite element models of the sign structures, with detailed modeling of the coupler connections.  It is anticipated that the physical fatigue tests would be performed on a simplified two-member assemblage, comprised of an aluminum column pipe and an aluminum truss chord pipe connected by a coupler.  Since it will be important to “match” the flexural stiffness of these elements to that of the end support and the main sign truss in typical sign structures, dimensions of the pipe elements will be determined after finite element analysis of a typical sign structure has been performed.  
McEnroe
Most new and replacement culverts with an inside vertical dimension of 48 inches or greater must be embedded and backfilled below the grade of the streambed by one foot or more to comply with environmental permit requirements.  KDOT’s Road Design Manual (Part C) does not address the hydraulic analysis and design of embedded culverts.  Most of the hydraulic relationships for pipe culverts in current manual are applicable only to circular and rectangular cross-sectional shapes with uniform roughness characteristics.  They do not apply to embedded circular cross-sections with flat bottoms or to conduits with rough bottoms and smooth sides and tops.  The inlet-control rating tables for circular pipe culverts are clearly not valid for embedded pipes.  New hydraulic analysis/design procedures are needed for embedded culverts in general and embedded pipe culverts in particular.  
Zheng
In a previous project with KDOT completed in 2013, it has been found that the spinning blades from wind turbines can create turbulence and that these rotational vortices can sustain strength and carry for miles, which may cause conflicts with the safe operation of aircraft.  Two general aviation airports in Kansas, the Rooks County Regional Airport and the Pratt Regional Airport, were used as examples of proposed wind farms that would be in relatively close proximity to an airport. As the results show, consideration must be given during the planning stage of wind farm development in relationship to its position near an airport or an area of high aircraft use, such as aerial applicators and air ambulance providers. In this proposed project, studies will be performed to draw the proper correlation between the hazard index developed and the safe operation of aircraft at low airspeeds and at low flight altitudes near or at a general aviation airport. Classifications of general aviation aircraft types and the relative locations and sizes of wind turbines to specific airports will be investigated using both theories and measurement.
Kondyli
Increased congestion levels at urban areas are forcing many agencies to consider alternative strategies for making better use of the existing capacity. Ramp metering is a strategy that has been widely used and it has been shown to be efficient and cost-effective in managing freeway facilities. Ramp metering has already been implemented along I-435 in the Kansas City area since 2008. There are plans to install ramp metering along I-35 (both directions), between K7 and the Kansas/Missouri state line, at seven on-ramps. The actual installation and operation of the ramp meters will occur in 2016. The goal of this project is to perform a before and after evaluation of ramp metering operations along the corridor.  Both traffic flow (e.g., speeds, travel times, throughput) and safety (number and type of accidents) measures will be used to evaluate ramp metering at the study corridor. 
 
 

KUTC Other Projects
  • Kansas Healthy Communities Initiative
  • K-TRAN Research Project Coordination
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