LARIMER COUNTY RURAL AREA ROAD STANDARDS

Table of Contents4.9.1.3 Lane Alignment ..................................................................................................................................4-94.9.1.4 Angle of Intersection ..........................................................................................................................4-94.9.1.5 Horizontal Alignment and Vertical Profile.........................................................................................4-94.9.1.6 Auxiliary Lanes ..................................................................................................................................4-94.9.1.7 Design Vehicles................................................................................................................................4-104.9.1.8 Curb Returns.....................................................................................................................................4-104.10 ROAD NAME SIGNS AND TRAFFIC CONTROL DEVICES...................................................................4-114.10.1 General..................................................................................................................................4-114.10.2 Traffic Signing.......................................................................................................................4-114.10.2.1 Type and Location of Signs............................................................................................................4-114.10.2.2 New Roadway.................................................................................................................................4-114.10.2.3 Sign Posts, Supports, and Mountings..............................................................................................4-114.10.2.4 Sign Reflectivity.............................................................................................................................4-124.10.2.5 Panel Guage....................................................................................................................................4-124.10.3 Intersections ..........................................................................................................................4-124.10.3.1 Road Name Signs at Intersections ..................................................................................................4-12CHAPTER 5 – GEOTECHNICAL STANDARDS AND PAVEMENT DESIGN ..............................5-15.1 SCOPE ................................................................................................................................................5-15.2 GENERAL ...........................................................................................................................................5-15.3 SOILS INVESTIGATION........................................................................................................................5-15.3.1 Existing Pavement .....................................................................................................................5-15.3.2 Soils Investigation Report Content............................................................................................5-15.3.3 Soil Samples ..............................................................................................................................5-25.3.4 Soil Grouping ............................................................................................................................5-25.3.5 Classification Testing ................................................................................................................5-25.3.6 Subgrade Support Testing .........................................................................................................5-35.3.6.1 Hveem Stabilometer ...........................................................................................................................5-35.3.6.2 Swell Tests..........................................................................................................................................5-35.3.7 Mitigation of Soils Problems.....................................................................................................5-35.4 PAVEMENT DESIGN STANDARDS........................................................................................................5-45.4.1 General Design Factors ............................................................................................................5-45.4.1.1 Minimum Thicknesses........................................................................................................................5-45.4.2 Special Considerations..............................................................................................................5-45.4.2.1 Staged Construction............................................................................................................................5-45.4.2.2 Full Depth Sections ............................................................................................................................5-45.4.2.3 Rehabilitating Existing Asphalt Roads ...............................................................................................5-45.4.2.4 Auxiliary Lanes ..................................................................................................................................5-45.5 FLEXIBLE PAVEMENT DESIGN............................................................................................................5-55.5.1 Definition...................................................................................................................................5-55.5.2 AASHTO Design Approach .......................................................................................................5-55.6 RIGID PAVEMENT DESIGN..................................................................................................................5-75.6.1 Definition...................................................................................................................................5-75.6.2 AASHTO Design Approach .......................................................................................................5-85.6.3 Material Standards....................................................................................................................5-85.7 SUBGRADE INVESTIGATION AND PAVEMENT DESIGN REPORT...........................................................5-9CHAPTER 6 – STORMWATER MANAGEMENT .............................................................................6-16.1 GENERAL ...........................................................................................................................................6-16.2 CROSS FLOW DRAINAGE STRUCTURES ..............................................................................................6-1CHAPTER 7 – BRIDGES AND MAJOR DRAINAGE STRUCTURES.............................................7-17.1 DESIGN STANDARDS ..........................................................................................................................7-17.2 IRRIGATION COMPANY APPROVAL.....................................................................................................7-17.2.1 General......................................................................................................................................7-17.2.2 Required Information ................................................................................................................7-17.2.3 Required Studies........................................................................................................................7-27.2.4 Final Plans and As-Built Drawings ..........................................................................................7-2Larimer County Rural Area Road StandardsOctober 22, 2007Page iii