FINAL DATA REPORT FOR THE SOILS DENSITY GAUGE (SDG) AND PAVEMENT QUALITY INDICATOR (PQI) LIMITED OBJECTIVE EXPERIMENT (LOE)

Transcription

1 FINAL DATA REPORT FOR THE SOILS DENSITY GAUGE (SDG) AND PAVEMENT QUALITY INDICATOR (PQI) LIMITED OBJECTIVE EXPERIMENT (LOE) November 2008 Fort Leonard Wood, Missouri SOILS DENSITY GAUGE PAVEMENT QUALITY INDICATOR 1

2 US Army Operational Test Command (OTC) Test and Evaluation Coordination Office () Fort Leonard Wood, Missouri TEOT-MST 6 January 2009 MEMORANDUM FOR: See Distribution SUBJECT: Final Data Report for the Soils Density Gauge (SDG) and Pavement Quality Indicator (PQI) Limited Objective Experiment (LOE) 1. Provided for your use is the Final Data Report for the Soils Density Gauge (SDG) and Pavement Quality Indicator (PQI) Limited Objective Experiment (LOE). A Microsoft Access database containing all data collected accompanies this report. 2. POC is Mr. Fred Cook, Chief, Test and Evaluation Coordination Office () or Mr. Clay Thompson, Experiment Officer,, Fort Leonard Wood, MO, phone (573) Distribution APM CE/MHE Attn: Lorraine Maynard 6501 East Eleven Mile Road Mail Stop 401, Room 2640 Warren, MI Freddie W. Cook Chief, OTC/ ASMRD-TAR-D/CE Tank-Automotive Research, Development and Engineering Center Construction Equipment Engineering Team Attn: Jeramie Childers 6501 East Eleven Mile Road Warren, MI DOTLD Directorate of Training and Leader Development U.S. Army Engineer School Attn: SFC Patterson, Michael T. 320 MANSCEN Loop, Ste 370 Fort Leonard Wood, MO

3 FINAL EXPERIMENT DATA REPORT FOR THE SDG and PQI LOE November 2008 REPORT PREPARED BY Mr. Clayton K. Thompson - EXPERIMENT OFFICER Mr. Clayton K. Thompson - DATA COLLECTOR Ms. Clara Leeber - 3

4 US ARMY OPERATIONAL TEST COMMAND TEST AND EVALUATION COORDINATION OFFICE FORT LEONARD WOOD, MISSOURI TEOT-MST 6 January 2009 MEMORANDUM FOR: U. S. Army Maneuver Support Center (MANSCEN), Capabilities Development and Integration Directorate (CDID), Requirements Determination Division (RDD) Assured Mobility, 320 MANSCEN Loop, Suite 141, Fort Leonard Wood, MO SUBJECT: Soils Density Gauge (SDG) and Pavement Quality Indicator (PQI) Limited Objective Experiment (LOE) Experiment Data Report 1. References: a. Capabilities Production Document (CDP) for Tester, Construction Materials, Moisture and Density, Draft Version, 24 July 2008 b. Limited Objective Experiment Plan, 29 October 2008, subject: Limited Objective Experiment (LOE) Plan for the Soils Density Gauge (SDG) and the Pavement Quality Indicator (PQI) 2. Introduction 2.1 Purpose: The purpose of the LOE was to determine if the TransTech Soils Density Gauge (SDG) and the Pavement Quality Indicator (PQI) are safe and viable alternatives to the Campbell Pacific MC-1 Nuclear Densometer currently used by the U.S. Army. Measurements taken on soil and asphalt test lanes by the Campbell-Pacific MC-1 Nuclear Densometer were compared to readings taken by the SDG and the PQI. The Campbell-Pacific MC-1 Nuclear Densometer requires special training, a license to operate, and has become increasingly difficult to transport. 2.1 System Description: The SDG and PQI are hand-held measuring/testing instruments developed by Trans-Tech. Both instruments are easily transported and do not contain nuclear material. See table 1-1 for Key Specifications as reported by TransTech. Also provided are the specifications for the Campbell-Pacific MC-1 Nuclear Densometer. 4

5 Table 1-1 Key Specifications as reported by TransTech Soil Density Gauge Pavement Quality Indicator Unit Dimensions 13 x 11 x x x 11 Unit Weight w/o Case 12.8 lb 16 lb Shipping Weight with Case 29.4 lb 27lb Storage Box Dimensions 17.5 x 21 x x x 17 Operating Temp - Ambient -20 F to 110 F -20 F to 110 F Operating Temp - Surface Surface not Frozen Up to 350 F Functions Wet and Dry Density, % Compaction, % Moisture Density, % Compaction, % Voids and Segregation Measurement Depth Up to 12 un-compacted layer of soil during or after User selected and adjustable from 1 to 4 compaction Sensing Area 11 diameter base 10 diameter base Recharge Time 4.5 Hours 4 Hours 2.2 Background: A requirement exists to develop/investigate a replacement for the Campbell- Pacific MC-1 Nuclear Densometer to measure soil moisture content and density as well as the density of asphalt. The SDG and PQI are intended to improve on the capability of the MC-1 by providing a replacement instrument that does not require certification to transport and is simple to use. The LOE compared measurements taken with the Campbell-Pacific MC-1 Nuclear Densometer, Sand Cone and SDG on compacted soil and measurements taken with the Campbell-Pacific MC-1 Nuclear Densometer and the PQI on hot asphalt. Depending on analysis of the data collected during the LOE, the SDG and PQI may be considered as material replacements for the Campbell-Pacific MC-1 Nuclear Densometer. 2.3 Experiment Conduct: Experiment was conducted at, Fort Leonard Wood, MO. This experiment focused on comparing measurements taken with the Campbell-Pacific MC-1 Nuclear Densometer and the SDG or PQI on newly constructed test lanes. Subject Matter Experts (SME) for this LOE are 21T, Technical Engineering Specialists. SMEs were provided by 1st Engineer Brigade and took all measurements. For soils testing, a total of two lanes were used; each divided into ten equal lots. Lanes 1 and 2 were designated as soils lanes and Lane 3 was the asphalt testing lane. A local asphalt contractor provided limestone screenings or tailings used in the soils lanes. The contractor delivered approximately 80 tons (four dump truck loads) of the screenings and then distributed each dump truck load with an asphalt paver. This ensured a uniform lift thickness of 8 inches. The actual length and width of the test lane placed by the contractor was approximately 160 feet long by 12 feet wide. This ensured that two test lanes, 60 feet long by 10 feet wide, could be marked on the soil and that all edges would be compacted. The test lanes were then compacted with a Caterpillar 563E vibratory roller. Test Lane 1 was compacted with 6 passes and Test Lane 2 was compacted with 12 passes. Engineer tape was used to mark each 60 by 10 test lane and to separate into 10 equal lots. See Figure 1 below. Figure 1 5

6 Lot 1 Lot 2 Lot 3 Lot 4 Lot 5 Lot 6 Lot 7 Lot 8 Lot 9 Lot Once lanes were marked and prior to starting the experiment, two random nuclear densometer measurements were taken per lane to ensure that compaction and moisture were at acceptable levels. Sieve analysis data for the material type being used was entered into the SDG and the experiment was ready to begin. The first measurements taken were with the SDG followed by measurements taken with two different Campbell-Pacific Nuclear Densometers provided by 1st Engineer Brigade. Measurements were completed in each lot prior to moving to the next lot. Dry density and moisture content data were recorded. Measurements were completed on Day 1 for twenty test lots. On Day 2, the 1 st Engineer Brigade provided 21T students to perform sand cone measurements for each lot. Students were supervised by Subject Matter Experts. After consulting with the asphalt contractor, a decision was made by the test team as to the location that asphalt testing would be conducted. The contractor had an on-going asphalt project on a range road that would be suitable for testing. Once all personnel were on site, a lane was marked on freshly placed and compacted asphalt. The lane was marked with chalk. Asphalt mix data was entered into the Pavement Quality Indicator (PQI) and testing began. The first measurements taken were with the PQI in the center of the test lot. A chalk outline was drawn around the PQI to depict the location that nuclear densometer measurements and core samples would be taken. After the PQI, sample measurements were again taken with two different nuclear densometers, utilizing the backscatter method. Unlike soils testing, the back-scatter method does not require a stake to be driven in the ground prior to taking measurements. In addition to the Campbell-Pacific Nuclear Densometer and SDG, additional measurements were taken by the Quality Control Inspector employed by the local contractor. The machine used by the QC Inspector was a Seaman model C300. Measurement data is provided in the MS Access Database. After all surface measurements were complete; a core sample was cut from each asphalt test lot by the contractor. Analyses of the core samples were completed the same day and results were provided to. 2.4 Limitations: Sand cone measurements were not taken at the same time as SDG and Nuclear Densometer measurements were taken. Sand cone testing materials were not available until Test Day 2. This resulted in a larger difference in Moisture Content percentages as the soil had an additional day to dry out. The SDG is not technologically ready to be used on all soils types at this time. This was known prior to the start of the LOE, and a suitable soil material was chosen for the experiment that would show the capabilities of the SDG. 2.5 Experiment Officer Observations: Initial reactions to the SDG and PQI by Soldiers and SMEs present on the test site were positive. Questionnaires completed by Soldiers and SMEs include positive comments on portability and ease of use. 6

7 Measurements taken with the SDG and then compared to the Campbell-Pacific Nuclear Densometer showed only a small average difference in dry density of 2.33 pounds per cubic foot and 0.81% in moisture content percentage. The measurements taken by the PQI appear to be more accurate than the Campbell-Pacific Nuclear Densometer when compared to core sample densities. The readings from the PQI differed by an average of 1.2 pounds per cubic foot and the best Nuclear Densometer differed by an average of 5.5 pounds per cubic foot. The SDG took less time to take 10 measurements with an average of 24 minutes than the Campbell-Pacific Nuclear Densometer which took an average of 45.5 minutes. Recommend that any decisions for fielding the SDG and PQI to the Army should consider more comprehensive technical information currently being generated by the Army Research and Development community. 3.0 POC: The POC for this report is Mr. Clay Thompson (clayton.k.thompson@us.army.mil) comm A Microsoft Access database containing all data collected accompanies this report. Encl Appendix A Event Schedule MS Access CD Experiment Database Freddie W. Cook Chief, OTC/ 7

8 Appendix A Event Schedule DATE Time ACTIVITY LOCATION Responsible Agency Resources Required Bucket Loader, Grader, Dump Nov Test Lane Construction, 1st Engr Bde Fort Leonard Wood Truck(s), Roller 17-Nov-08 Demographics Experiment Player Training TransTech SDG and PQI Instruction Manuals Lunch Fort Leonard Wood Pilot Test, Soils Trials SDG, Sand Cone, SME, Data 1700-UTC Daily AAR, Safety 18-Nov Nov Nov Soils Trials SDG, Sand Cone, SME, Data Lunch Fort Leonard Wood Soils Trials SDG, Sand Cone, SME, Data 1700-UTC Daily AAR, Safety Soils Trials SDG, Sand Cone, SME, Data Lunch Fort Leonard Wood Soils/Asphalt Trials SDG, Sand Cone, PQI, SME, Data 1700-UTC Daily AAR, Safety Asphalt Trials PQI, SME, Data Collector, Data Collection Lunch Fort Leonard Wood Asphalt Trials PQI, SME, Data Collector, Data Collection 1700-UTC Daily AAR, Safety 21-Nov Make-Up Trials as Required SDG, PQI, SME, Data Fort Leonard Wood Lunch Site Clean-Up 1700-UTC End of Experiment AAR, Safety 8