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                        Low-Cost Treatments for Horizontal Curve Safety 2016


            
            In This Section
        Roadway Departure Safety
                Strategic Approach
                                Strategic Plan
                Crash Emphasis Brochures
                Focused Approach
                Noteworthy Practices
                Partner Resources
                Keep Vehicles on the Road
                                Pavement Friction
                Horizontal Curve Safety
                Rumble Strips and Rumble Stripes
                Nighttime Visibility
                Provide for a Safe Recovery
                                SafetyEdge
                Clear Zones
                Reduce Crash Severity
                                Overview
                Hardware Eligibility Letters
                Focus on Reducing Rural Roadway Departures (FoRRRwD)
                                Overview
                All Public Roads
                Proven Countermeasures
                Systemic Approach
                Safety Action Plans
                FoRRRwD Resources
                
                Glossary
Glossary



**Term**
			**Description**Acrylic material
			Binder material used in high friction surface treatment that holds the aggregate firmly to the pavement.ADT
			Average Daily Traffic â€“ the traffic volume of a road measured in vehicles per day.Advisory speed plaque
			A sign that is placed below a Horizontal Alignment sign to advise motorists of the safe speed through the curve.Ball bank indicator
			An inclinometer that is used for determining safe curve speeds for horizontal curves.Cable barrier
			A flexible barrier made from wire rope supported between frangible posts.Calcined bauxite aggregate
			A hard, coarse aggregate used in high friction surface treatment.Clear Zone
			The unobstructed traversable area provided beyond the edge of the through traveled way for the recovery of errant vehicles, as defined by AASHTO.CMF
			Crash Modification Factor â€“ a multiplicative factor used to compute the expected number of crashes after implementing a countermeasure.CMF Clearinghouse
			A website that provides the largest collection of CMFs for geometric design elements and traffic control devices available in the United States.Compound curves
			Two or more tangential, consecutive curves.Curve Deliniation
			Treatments that enhance the conspicuity of a curve (e.g., wider edge line, higher retroreflectivity of signs, postmounted delineators, chevrons, raised pavement markings).Concrete safety shape
			A rigid barrier that does not deflect.Delineators
			A device mounted above the roadway surface and along the side of the road in a series to indicate roadway alignment.Epoxy material
			Binder material used in the application of high friction surface treatment that hold the aggregate firmly to the pavement.FARS
			Fatality Analysis Reporting System â€“ a nationwide census providing annual data regarding fatal injuries in motor vehicle traffic crashes.Guardrail
			A semi-rigid barrier usually either a steel box beam or W-beam that deflect less than flexible barriers.HFST
			High Friction Surface Treatment â€“ a thin layer of aggregate bonded to the pavement surface designed to increase friction and compensate for sharp curves.Milled
			Milled rumble strips are made by a machine with a rotary cutting head, creating a smooth, uniform, and consistent groove in the pavement. They cause tire noise and vehicle vibration when traversed.MUTCD
			Manual on Uniform Traffic Control Devices â€“ defines the standards used by road managers nationwide to install and maintain traffic control devices on all public streets, highways, bikeways, and private roads open to public traffic.Pavement grooving
			A pavement countermeasure technique to apply longitudinal or transverse cuts onto the pavement surface to increase or restore pavement friction.Pavement raveling
			Deterioration of the pavement surface caused by aggregate particles becoming dislodged.Retroreflective
			A material or device that reflects light back to its source.RSA
			Road Safety Audit â€“ a formal safety performance examination of an existing or future road or intersection by an independent, multidisciplinary team.Safety EdgeSM
			A paving technique used system-wide to improve pavement durability and reduce crashes by shaping and consolidating the pavement edge into a 30 degree wedge.Superelevation
			The banking of a horizontal curve.Systemic approach
			The analysis of crash data on a system-wide basis that considers identifying factors that indicate higher risks for severe crashes.
      
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      ‹ REFERENCES
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                    Appendix A: Low-Cost Safety Improvements in Pennsylvania ›
                
                Book:Low-Cost Treatments for Horizontal Curve Safety 2016
              CHAPTER 1. INTRODUCTION
                CHAPTER 2. THE TWO COMPONENTS OF SAFETY IMPROVEMENT: SITE ANALYIS AND THE SYSTEMIC APPROACH
                CHAPTER 3. MARKINGS
                CHAPTER 4. SIGNS
                CHAPTER 5. PAVEMENT COUNTERMEASURES
                CHAPTER 6. ROADSIDE IMPROVEMENTS
                CHAPTER 7. ADDRESSING INTERSECTIONS IN CURVES
                REFERENCES
                Glossary
                Appendix A: Low-Cost Safety Improvements in Pennsylvania
                Appendix B: Systemic Improvements in Minnesota
                Appendix C: Application of Edge Lines in Missouri
                Appendix D: Upgrading Curve Signing in Ohio
                APPENDIX E: Application Of Sequential Dynamic Curve Warning Systems (SDCWS)
                Appendix F: Application of High Friction Surface Treatment in Kentucky
                Appendix G: Every Day Counts – High Friction Surface Treatments
                Appendix H: Utility Pole Management in New Jersey
                ACRONYMS U.S. DEPARTMENT OF TRANSPORTATION

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