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From page 1... ... Research Results Digest 347 August 2010 C O N T E N T S Introduction, 1 Input Parameters for Unbound Materials Required by the EICM, 2 Development of the National Database of Soil Properties from the NRCS Database, 2 Processing NRCS Raw Data, 3 Creating the Master File, 3 Properties and Characteristics of the Master File, 3 Missing Information in the Master File, 3 Preliminary Reduction of Soil Unit Data, 5 Selecting the Proper Component to Represent the Map Unit, 5 Data Sorting by Map Unit, 5 Properties Included in the National Database, 5 Computed Parameters, 15 GIS and Cartographic Process, 18 Software, 18 Data Collection, 18 Data Preparation, 18 User Interface, 19 Using the National Database, 19 Summary, 19 References, 23 INTRODUCTION The Mechanistic-Empirical Pavement Design Guide (MEPDG) was developed in NCHRP Project 1-37A to give pavement designers a tool to assess, for a specific design problem, the sensitivity of the critical parameters that influence pavement performance. Read the entire page →
From page 2... ... This Research Results Digest (RRD) summarizes the approach taken to create the national database of unbound material properties from soil properties directly measured in the field for agricultural and geotechnical (pavement) Read the entire page →
From page 3... ... The NRCS information is divided among three soil geographic databases, which differ primarily in the scale used for mapping the different soil units. The three soil geographic databases are: 1. Read the entire page →
From page 4... ... Figure 1 Soil survey available data. Read the entire page →
From page 5... ... vast geographic area covered by the project. Table 3 presents the distribution by state of the soil units with missing information. Read the entire page →
From page 6... ... 6Table 1 Initial soil properties selected for the master database Column Label Column Name Map Unit Symbol musym Map Unit Name muname Component Name compname AASHTO Classification aashtocl AASHTO Group Index -- Representative Value aashind_r Unified unifiedcl Top Depth -- Representative Value hzdept_r Bottom Depth -- Representative Value hzdepb_r Thickness -- Representative Value hzthk_r #4 -- Representative Value sieveno4_r #10 -- Representative Value sieveno10_r #40 -- Representative Value sieveno40_r #200 -- Representative Value sieveno200_r Total Clay -- Representative Value claytotal_r LL -- Representative Value ll_r PI -- Representative Value pi_r Db 0.1 bar H2O -- Representative Value dbtenthbar_r Db 0.33 bar H2O -- Representative Value dbthirdbar_r Db 15 bar H2O -- Representative Value dbfifteenbar_r Dp partdensity Ksat -- Representative Value ksat_r 0.1 bar H2O -- Representative Value wtenthbar_r 0.33 bar H2O -- Representative Value wthirdbar_r 15 bar H2O -- Representative Value wfifteenbar_r Satiated H2O -- Representative Value wsatiated_r LEP -- Representative Value lep_r CaCO3 -- Representative Value caco3_r Gypsum -- Representative Value gypsum_r CEC-7 -- Representative Value cec7_r Water Table Depth -- Annual -- Minimum wtdepannmin Water Table Depth -- April -- June -- Minimum wtdepaprjunmin Bedrock Depth -- Minimum brockdepmin Corrosion Concrete corcon Corrosion Steel corsteel EC -- Representative Value ec_r Available Water Storage 0–150 cm aws0150wta SAR -- Representative Value sar_r pH H2O -- Representative Value ph1to1h2o_r Kw kwfact Kf kffact AWC -- Representative Value awc_r Db oven dry -- Representative Value dbovendry_r Comp % -- Representative Value comppct_r Hydrologic Group hydgrp MAAT -- Representative Value airtempa_r Elevation -- Representative Value elev_r ENG -- Local Roads and Streets englrsdcd Map Unit Key mukey Component Key cokey Chorizon Key chkey Chorizon AASHTO Key chaashtokey Chorizon Unified Key chunifiedkey Read the entire page →
From page 7... ... Table 2 Soil properties of master database Column Label Description Map Unit Symbol Map Unit Name Component Name AASHTO Classification AASHTO Group Index -- Representative Value Unified Top Depth -- Representative Value Bottom Depth -- Representative Value Thickness -- Representative Value #4 -- Representative Value #10 -- Representative Value #40 -- Representative Value #200 -- Representative Value Total Clay -- Representative Value LL -- Representative Value PI -- Representative Value The symbol used to uniquely identify the soil map unit in the soil survey. Correlated name of the map unit (recommended name or field name for surveys in progress) Read the entire page →
From page 8... ... Db 0.1 bar H2O -- Representative Value Db 0.33 bar H2O -- Representative Value Db 15 bar H2O -- Representative Value Dp Ksat -- Representative Value 0.1 bar H2O -- Representative Value 0.33 bar H2O -- Representative Value 15 bar H2O -- Representative Value Satiated H2O -- Representative Value LEP -- Representative Value CaCO3 -- Representative Value Gypsum -- Representative Value CEC-7 -- Representative Value Water Table Depth -- Annual -- Minimum Water Table Depth -- April -- June -- Minimum Bedrock Depth -- Minimum The oven dried weight of the less than 2 mm soil material per unit volume of soil at a water tension of 1⁄10 bar. The oven dry weight of the less than 2 mm soil material per unit volume of soil at a water tension of 1⁄3 bar. Read the entire page →
From page 9... ... Corrosion Concrete Corrosion Steel EC -- Representative Value Available Water Storage 0–150 cm SAR -- Representative Value pH H2O -- Representative Value Kw Kf AWC -- Representative Value Db oven dry -- Representative Value Comp % -- Representative Value Hydrologic Group MAAT -- Representative Value Elevation -- Representative Value ENG -- Local Roads and Streets Map Unit Key Component Key Chorizon Key Susceptibility of concrete to corrosion when in contact with the soil. Susceptibility of uncoated steel to corrosion when in contact with the soil. Read the entire page →
From page 10... ... 10 Table 3 Soil units with missing information State Name Map Units Map Units without Information 1 Alabama 1394 30 2 Alaska 1818 115 4 Arizona 1229 15 5 Arkansas 1073 38 6 California 4203 182 8 Colorado 2013 121 9 Connecticut 354 10 0 Delaware 43 0 12 Florida 2984 272 13 Georgia 2722 21 0 Hawaii 378 0 16 Idaho 1506 45 17 Illinois 1344 28 18 Indiana 1372 18 19 Iowa 1954 33 20 Kansas 1116 33 21 Kentucky 607 6 22 Louisiana 2259 127 23 Maine 1236 172 24 Maryland 568 79 25 Massachusetts 465 56 26 Michigan 2218 63 27 Minnesota 2400 199 28 Mississippi 1255 20 29 Missouri 904 25 30 Montana 4284 2443 31 Nebraska 2332 419 32 Nevada 2898 24 33 New Hampshire 385 42 34 New Jersey 363 13 35 New Mexico 1985 37 36 New York 3253 314 37 North Carolina 1371 1363 38 North Dakota 2291 1564 39 Ohio 1022 22 40 Oklahoma 1714 74 41 Oregon 1252 76 42 Pennsylvania 1228 25 72 Puerto Rico 217 13 44 Rhode Island 110 4 45 South Carolina 825 101 46 South Dakota 1589 241 47 Tennessee 1402 35 48 Texas 3892 136 49 Utah 1471 61 50 Vermont 273 5 51 Virginia 940 82 53 Washington 2350 83 54 West Virginia 362 8 55 Wisconsin 1220 84 56 Wyoming 1131 49 No State Designation 736 59 78311 9085 % Map Units without Soil Information . Read the entire page →
From page 11... ... Table 4 Example of component by map unit muname mukey aashtocl layer hzdept hzdepb hzthk comppct sieve10 sieve40 sieve200 ll pi Rogert-Rock outcrop 677056 A-2 1 0 10 10 33 62.5 42.5 30 30 2.5 Rogert-Rock outcrop 677056 A-1 2 10 36 26 33 35 25 12.5 0 Rogert-Rock outcrop 677056 A-2 1 0 8 8 17 62.5 50 30 0 Rogert-Rock outcrop 677056 A-2 2 8 25 17 17 62.5 42.5 35 27.5 7.5 Rogert-Rock outcrop 677056 A-1 3 25 48 23 17 20 14 7.5 0 Rogert-Rock outcrop 677056 A-2-4 1 0 8 8 10 95 70 30 22.5 2.5 Rogert-Rock outcrop 677056 A-6 2 8 30 22 10 80 62.5 45 35 15 Rogert-Rock outcrop 677056 A-6 3 30 51 21 10 65 52.5 35 35 12.5 Rogert-Rock outcrop 677056 A-2-6 4 51 84 33 10 37.5 25 17.5 35 12.5 Rogert-Rock outcrop 677056 A-2 1 0 18 18 6 82.5 55 35 0 Rogert-Rock outcrop 677056 A-2 2 18 25 7 6 62.5 42.5 30 25 10 Rogert-Rock outcrop 677056 A-6 3 25 36 11 6 80 60 45 32.5 12.5 Rogert-Rock outcrop 677056 A-1 1 0 25 25 6 92.5 55 25 0 Rogert-Rock outcrop 677056 A-2 2 25 66 41 6 65 35 27.5 35 12.5 Rogert-Rock outcrop 677056 A-1 1 13 30 17 3 42.5 32.5 25 20 2.5 Rogert-Rock outcrop 677056 A-1 2 30 48 18 3 22.5 17.5 10 20 2.5 Rogert-Rock outcrop 677056 A-1 1 0 25 25 3 62.5 40 20 0 Rogert-Rock outcrop 677056 A-2 2 25 71 46 3 35 27.5 17.5 25 10 Rogert-Rock outcrop 677056 A-4 1 0 8 8 2 95 87.5 65 30 2.5 Rogert-Rock outcrop 677056 A-4 2 8 152 144 2 95 87.5 72.5 30 10 Read the entire page →
From page 12... ... Table 5 Soil Properties Included in the National Database Column Label Parameter Description Units MapChar MapunitSym MapUnitNam_01 Mukey_01 Compname_01 AASHTO_01 GroupIndex_01 TopDepth_01 BottDepth_01 Thickness_01 Pass#4_01 In. Read the entire page →
From page 13... ... Pass#10_01 Pass#40_01 Pass#200_01 Clay0.002_01 LL_01 PI_01 Ksat_01 Wsatiated_01 af_01 nf_01 mf_01 hr_01 (continued on next page) Passing # 10 Passing # 40 Passing # 200 Passing Sieve 0.002 mm Liquid Limit Plasticity Index Sat'd Hydraulic Conductivity Satiated H2O A N M Hr % % % % % % ft/hr % Psi Psi Soil fraction passing a number 10 sieve (2.00-mm-square opening) Read the entire page →
From page 14... ... Table 5 (Continued) Column Label Parameter Description Units CBR_FROM_PI_01 MR_FROM_PI_01 Elev_01 Comppct_01 BedroDepth_01 wtdepannmin_01 wtdepaprjunmin_01 California Bearing Ratio Resilient Modulus Elevation Comp % Bedrock Depth -- Minimum Water Table Depth -- Annual -- Minimum Water Table Depth -- April -- June -- Minimum % Psi M % Ft Ft Ft Measured pressure required to penetrate a soil sample with a plunger of standard area. Read the entire page →
From page 15... ... In addition to the SWCC parameters necessary for the MEPDG, many other relevant MEPDG soil parameters were also computed, checked, and incorporated in the database. The following additional engineering properties were estimated based on the original database information and then incorporated into the National Database: • Group index • Layer thickness • D60, • Weighted Plasticity Index (wPI) Read the entire page →
From page 16... ... "service performance" of the soil, particularly when it is used as a highway pavement subgrade. The group index can be calculated by the empirical equation given in AASHTO M145-91, Standard Specification for Classification of Soils and Soil-Aggregate Mixtures for Highway Construction Purposes: Where: P200 = Passing the No. Read the entire page →
From page 17... ... materials. The resilient modulus can then be estimated from the CBR by using the expression: that is used in the MEPDG (Witczak et al., 2001) Read the entire page →
From page 18... ... grain size distribution passes (D60) , in millimeters. Read the entire page →
From page 19... ... After identifying each unique Mukey, a Map Character was assigned to each one; each Mukey was assigned a three-character alpha-numeric code. Since each Mukey is at least six characters long, use of the Map Character substantially reduced the space required in the database for labeling purposes. Read the entire page →
From page 20... ... 28 31 97 5 64 1 1 1 6 1 91 7 1 0 1 8 1 2 1 51 3 1 4 89°0'0"W 89°0'0"W 90°0'0"W 90°0'0"W 91°0'0"W 91°0'0"W 92°0'0"W 92°0'0"W 93°0'0"W 93°0'0"W 94°0'0"W 94°0'0"W 33°0'0"N 33°0'0"N 32°0'0"N 32°0'0"N 31°0'0"N 31°0'0"N 30°0'0"N 30°0'0"N 29°0'0"N 29°0'0"N Created by: Natalie Lopez, Gustavo Torres, and Dr.Claudia Zapata 0 20 40 60 80 Miles This map was produced for the Department of Civil and Environmental Engineering at Arizona State University. State boundaries and roads courtesy of the US Census. Read the entire page →
From page 21... ... 21 212 EZ8 EU9 FC0 FB5 FA4 FA5 FC9 FB4 EW5 FC9 EZ8 EW5 FD2 FC3 FB3 FA4 FB4 FA8 EX0 EX3 FB4 FD1 FA7 FB3 212 212 FA4 FB3 FJ9 FA5 FD2 FC7 FB4 FC1 FA5 FA4 FD2 FC2 EZ8 FA8 212 FC0 FB7 EX0 FA2 FC1 FD4 FC0 EZ6 FB4 FA5 EW5 FD4 EY8 FD1 FC6 FC5 FC6 FC6 FA4 FC5 FB3 FB3 EY9 EZ8 FD1 EW4 EU9 FB6 EX0 FC5 FB5 FD1 EU9 EY8 EZ9 FC5 FC9 FA3 EY9 FA4 EY9 EY8 FC0 ET9 FA5 EZ8 FB7 EZ6 FD2 EZ1 EX9 FC5 FD1 FA2 EY9 FA8 EY9 FD2 FD4 EX0 FD8 EZ7 EZ6 FD1 EY8 FD2 EW5 FC2 FB8 FD8 EZ6 EX0 EZ6 FD6 EZ4 FC7 FC5 FD8 FB8 212 FD7 FD1 FD0 FA7 EX8 EX0 FA4 FC5 EY6 FC5 FA5 FD1 FC0 FA4 FC9 FA7 FA5 FD1 EX7 I-12 I-10 I-55 I-310 I-610 I-12 I-10 90°0'0"W 90°0'0"W 90°10'0"W 90°10'0"W 90°20'0"W 90°20'0"W 90°30'0"W 90°30'0"W 90°40'0"W 90°40'0"W 90°50'0"W 90°50'0"W 91°0'0"W 30°30'0"N 30°30'0"N 30°20'0"N 30°20'0"N 30°10'0"N 30°10'0"N 30°0'0"N 30°0'0"N 29°50'0"N 29°50'0"N 2 8 31 97 5 64 11 16 1917 10 18 12 1513 14 Created by: Natalie Lopez Data by: Gustavo Torres, Claudia Zapata 0 5 10 15 20 Miles Date: 8/11/09 Projected Coordinate System: NAD 1983, State Plane, Louisiana North, FIPS 1701 Projection: Lambert Conformal Conic This map was produced for the Department of Civil and Environmental Engineering at Arizona State University. Soil unit data was downloaded from the USDA NRCS. Read the entire page →
From page 22... ... National Catalogue of Natural Subgrade Properties Needed for the MEPDG Input Map Char FA5 Mapunit Key 667683 Mapunit Name Springfield-Natalbany-Encrow-Colyell (s2864) Component Name Colyell Top Layer Layer 2 Layer 3 Layer 4 Layer 5 Layer 6 Layer 7 Layer 8 Layer 9 AASHTO Classification A-4 A-4 A-7-6 A-7-6 AASHTO Group Index 6 5 32 19 Top Depth (in.) Read the entire page →
From page 23... ... measured materials properties rather than empirical relationships. The database will greatly assist pavement designers using the MEPDG and other pavement design methods. Read the entire page →
From page 24... ... Transportation Research Board 500 Fifth Street, NW Washington, DC 20001 These digests are issued in order to increase awareness of research results emanating from projects in the Cooperative Research Programs (CRP) Read the entire page →

From page 1...

... Research Results Digest 347 August 2010 C O N T E N T S Introduction, 1 Input Parameters for Unbound Materials Required by the EICM, 2 Development of the National Database of Soil Properties from the NRCS Database, 2 Processing NRCS Raw Data, 3 Creating the Master File, 3 Properties and Characteristics of the Master File, 3 Missing Information in the Master File, 3 Preliminary Reduction of Soil Unit Data, 5 Selecting the Proper Component to Represent the Map Unit, 5 Data Sorting by Map Unit, 5 Properties Included in the National Database, 5 Computed Parameters, 15 GIS and Cartographic Process, 18 Software, 18 Data Collection, 18 Data Preparation, 18 User Interface, 19 Using the National Database, 19 Summary, 19 References, 23 INTRODUCTION The Mechanistic-Empirical Pavement Design Guide (MEPDG) was developed in NCHRP Project 1-37A to give pavement designers a tool to assess, for a specific design problem, the sensitivity of the critical parameters that influence pavement performance.