Comprehensive Subgrade Deflection Acceptance Criteria - Pilot Implementation Report

This report has presents the findings of implementations of pilot specifications for subgrade acceptance based on measured deflections. The reconfigured rolling wheel deflectomter (RWD), portable truck-mounted deflection measurement systems, and dynamic cone penetrometer (DCP) were utilized on four subgrade construction projects during the 2001 construction season. Comparative nuclear density readings were obtained at selected locations within each project. Comparative soil stiffness gauge readings were also obtained on 2 of the pilot projects The research findings from this and previous study phases indicate that deflection test results may be appropriate for identifying areas of poor in-place stability within constructed subgrades. However, deflection testing alone may not provide all of the data necessary to properly differentiate acceptable and non-acceptable subgrade stabilities. It is important to note that deflection test results are related to the moisture-density conditions at the time of testing. Soils that show acceptable results (i.e., low deflections) may subsequently weaken due to changes in moisture content, freezing/thawing, etc. In instances where subgrade acceptance is well in advance of base course application, subgrade moisture changes may result in decreased soil support. For those conditions where soil compaction has been conducted at a moisture state near optimum, surface deflections should be correlated to the achieved level of compaction. The overall objectives of this research have been met, particularly in the development of useful correlations between subgrade deflections and in-place subgrade stability as measured by the California Bearing Ratio (CBR). Deflection data collected to date using instrumentation on the axles of loaded quad-axle trucks indicates this data source should be adequate for acceptance testing. It is recommended that implementations of deflection acceptance testing be conducted during the 2002 construction season on selected projects using a deflection threshold of 1.50 inches to identify areas which would not provide sufficient stability for subsequent construction operations. For use within Year 2002 implementations, this threshold value is recommended for use to identify potentially “failed” test locations. The project engineer should retain the right to require corrective actions to improve subgrade conditions based on the magnitude and extent of failed readings

Development of Comprehensive Subgrade Deflection Acceptance Criteria - Phase 3 Report

This report has presented the findings of Phase III of research conducted to aid in the development of subgrade deflection acceptance criteria for WisDOT. The reconfigured rolling wheel deflectomter (RWD), portable truck-mounted deflection measurement systems, and automated dynamic cone penetrometer (DCP) were utilized on subgrade construction projects throughout the 2000 construction season. Laboratory analysis of soil properties, including Proctor, CBR and unconfined compression tests, were also conducted. The research findings have validated the concept of using deflection testing results to identify areas of poor in-place stability within constructed subgrades. It is recommended that pilot implementations of deflection acceptance testing be conducted in conjunction with subgrade penetration testing and moisture controls until more data has been collected, especially in moisture sensitive fine grained soil types. The use of deflection acceptance testing, in conjunction with in-situ penetration tests, should provide the data necessary to determine if the in-place support capacity for a given soil is sufficient to provide a stable construction platform for subsequent paving operations. However, it is important to note that both the RWD and DCP test results are related to the moisture-density conditions at the time of testing. Soils that show acceptable results (i.e., low deflections) may subsequently weaken due to changes in moisture content, freezing/thawing, etc. In instances where subgrade acceptance is well in advance of base course application, subgrade moisture changes may result in decreased soil support

Marquette Interchange Phase I Final Report

This report provides details on the design, installation and monitoring of a pavement instrumentation system for the analysis of load-induced stresses and strains within a perpetual HMA pavement system. The HMA pavement was constructed as part of an urban highway improvement project in the City of Milwaukee, Wisconsin. The outer wheel path of the outside lane was instrumented with asphalt strain sensors, base and subgrade pressure sensors, subgrade moisture and temperature sensors, HMA layer temperature sensors, traffic wander strips and a weigh in motion system. Environmental sensors for air temperature, wind speed and solar radiation are also included. The system captures the pavement response from each axle loading and transmits the data through a wireless link to a resident database at Marquette University. The collected data will be used to estimate the fatigue life of the perpetual HMA pavement and to modify, as necessary, pavement design procedures used within the State of Wisconsin

Perpetual Pavement Instrumentation for the Marquette Interchange Project-Phase 1

This report provides details on the design, installation and monitoring of a pavement instrumentation system for the analysis of load-induced stresses and strains within a perpetual HMA pavement system. The HMA pavement was constructed as part of an urban highway improvement project in the City of Milwaukee, Wisconsin. The outer wheel path of the outside lane was instrumented with asphalt strain sensors, base and subgrade pressure sensors, subgrade moisture and temperature sensors, HMA layer temperature sensors, traffic wander strips and a weigh in motion system. Environmental sensors for air temperature, wind speed and solar radiation are also included. The system captures the pavement response from each axle loading and transmits the data through a wireless link to a resident database at Marquette University. The collected data will be used to estimate the fatigue life of the perpetual HMA pavement and to modify, as necessary, pavement design procedures used within the State of Wisconsin

Aquaponics: A Sustainable Food Production System That Provides Research Projects for Undergraduate Engineering Students

Aquaponics is a closed-loop, recirculating water system in which plants and fish grow together mutualistically. Aquaponics resembles a natural river or lake basin in which fish waste serves as nutrients for the plants, which in turn clean the water for the fish. Tilapia and salad greens or herbs are common fish and plants grown in an aquaponics system. The external inputs to an aquaponics system are fish food, minimal amount of water, and energy for lighting and heating the water for the fish and plants. Aquaponics is a sustainable, efficient system to raise fish protein and vegetables for human consumption. Aquaponics systems can be located anywhere in the world where there is adequate energy with a minimal amount of water. Aquaponics is particularly suited to arid climates because it uses much less water to grow plants than soil-based systems. In fact, the only water that is lost is evaporation and transpiration from the plants. Although the field of aquaponics is growing world-wide, the capital and operational costs of producing the plants and fish have not been quantified intensively in the peer-reviewed literature. The relationship between the amount of external energy (fish food plus energy for light and heat) to the output (weight of fish and plants) has not been measured well for aquaponics units in temperate climates. The lack of quantification of the input-output has suppressed aquaponics progress because it is difficult to compare the cost of fish and salad greens grown with aquaponics and conventional methods, such as aquaculture and soil-based methods. The diverse nature of aquaponics and the need to quantify the relationship between input-output presents opportunities for research projects for undergraduate engineering students in Mechanical, Electrical, and Civil Engineering. The following are examples: Sensors: What type of sensors are ideal to measure air and water temperature, water PH, dissolved O2, and nitrates? Thermodynamics: What type of water heating system is most efficient to maintain desirable water and air temperature? Water Quality: What are the optimal methods to filter out the solid fish waste (feces) and introduce necessary bacteria into the system? Hydraulics: What size of pump and diameter of pipe are needed to maintain optimal flow rate? System Design: What are the optimal ratios between fish tank volume and grow area volume? What is the optimal drop in water level between components to utilize the gravity system? Marquette University College of Engineering is building a laboratory to conduct aquaponics research. The design of the system along with the lessons learned will be presented, along with a detailed list of specific projects for engineering students. Lessons learned from this research will aid the development of aquaponics in temperate climates but also possibly in subtropical and tropical region

Marquette interchange perpetual pavement instrumentation project : phase I final report

158 p.This report provides details on the design, installation and monitoring of a pavement instrumentation system for the analysis of load-induced stresses and strains within a perpetual hot mix asphalt (HMA) pavement system. The HMA pavement was constructed as part of an urban highway improvement project in the City of Milwaukee, Wisconsin. The outer wheel path of the outside lane was instrumented with asphalt strain sensors, base and subgrade pressure sensors, subgrade moisture and temperature sensors, HMA layer temperature sensors, traffic wander strips and a weigh in motion system. Environmental sensors for air temperature, wind speed and solar radiation are also included. The system captures the pavement response from each axle loading and transmits the data through a wireless link to a resident database at Marquette University. The collected data will be used to estimate the fatigue life of the perpetual HMA pavement and to modify, as necessary, pavement design procedures used within the State of Wisconsin