Functional Part: Guardrail

Name

Guardrail

Identifier

fp_guardrail

Overview

This functional part defines the requirements for modeling and exchanging guardrail information in a highway BIM environment. Guardrails are longitudinal barrier systems providing edge protection at embankments, bridge approaches, and roadside obstacles. These safety systems include w-beam, thrie-beam, and cable guardrail types, each with specific MASH test level ratings and terminal treatments.

Results

Purpose

The purpose of this functional part is to standardize the exchange of guardrail information between design tools and construction systems, enabling roadside safety analysis and warrant verification, MASH test level compliance documentation, integration with crash testing data and performance evaluation, terminal treatment coordination (ET-2000, FLEAT, etc.), and quantity extraction for procurement and installation.

Concepts

Information Needed Entity/Pset/Functional Part MAN REC OPT NOT
Guardrail system type Pset_GuardrailFeatures.GuardrailType IfcPropertySingleValue::IfcLabel X      
MASH test level rating Pset_GuardrailFeatures.TestLevel IfcPropertySingleValue::IfcLabel X      
Terminal treatment type Pset_GuardrailFeatures.TerminalType IfcPropertySingleValue::IfcLabel   X    
Post spacing dimension Pset_GuardrailLayout.PostSpacing IfcPropertySingleValue::IfcPositiveLengthMeasure   X    
Unique identifier for guardrail element IfcCivilElement.GlobalId IfcGloballyUniqueId X      
Object identification code Pset_Identification.ObjectID IfcPropertySingleValue::IfcLabel X      
Feature designation code Pset_Identification.FeatureID IfcPropertySingleValue::IfcLabel   X    
Feature description text Pset_Identification.FeatureDescription IfcPropertySingleValue::IfcText   X    
Survey feature code Pset_Identification.SurveyFeatureCode IfcPropertySingleValue::IfcLabel   X    
Referenced alignment identifier Pset_AlignmentDataLinear.AlignmentIDReference IfcPropertySingleValue::IfcLabel X      
Referenced corridor identifier Pset_AlignmentDataLinear.CorridorIDReference IfcPropertySingleValue::IfcLabel X      
Begin station value Pset_AlignmentDataLinear.StationBegin IfcPropertySingleValue::IfcLengthMeasure X      
Begin station offset Pset_AlignmentDataLinear.StationOffsetBegin IfcPropertySingleValue::IfcLengthMeasure X      
End station value Pset_AlignmentDataLinear.StationEnd IfcPropertySingleValue::IfcLengthMeasure X      
End station offset Pset_AlignmentDataLinear.StationOffsetEnd IfcPropertySingleValue::IfcLengthMeasure X      
Reference point location Pset_AlignmentDataLinear.ReferencePointLocation IfcPropertySingleValue::IfcLabel X      
State plane northing coordinate at begin Pset_StatePlaneCoordinatesLinear.NorthingBegin IfcPropertySingleValue::IfcLengthMeasure   X    
State plane easting coordinate at begin Pset_StatePlaneCoordinatesLinear.EastingBegin IfcPropertySingleValue::IfcLengthMeasure   X    
State plane northing coordinate at end Pset_StatePlaneCoordinatesLinear.NorthingEnd IfcPropertySingleValue::IfcLengthMeasure   X    
State plane easting coordinate at end Pset_StatePlaneCoordinatesLinear.EastingEnd IfcPropertySingleValue::IfcLengthMeasure   X    
LRS postmile begin value Pset_LRSDataLinear.PostmileBegin IfcPropertySingleValue::IfcLengthMeasure     X  
LRS postmile end value Pset_LRSDataLinear.PostmileEnd IfcPropertySingleValue::IfcLengthMeasure     X  
LRS route identifier Pset_LRSDataLinear.LRSRouteID IfcPropertySingleValue::IfcLabel     X  
GPS latitude at begin Pset_GPSCoordinatesLinear.LatitudeBegin IfcPropertySingleValue::IfcReal     X  
GPS longitude at begin Pset_GPSCoordinatesLinear.LongitudeBegin IfcPropertySingleValue::IfcReal     X  
GPS latitude at end Pset_GPSCoordinatesLinear.LatitudeEnd IfcPropertySingleValue::IfcReal     X  
GPS longitude at end Pset_GPSCoordinatesLinear.LongitudeEnd IfcPropertySingleValue::IfcReal     X  
GPS control point reference Pset_GPSCoordinatesLinear.GPSControlPoints IfcPropertySingleValue::IfcText     X  

Examples

Example 1: Embankment Guardrail Safety Design

Use Case: Model guardrail system for steep embankment section to meet roadside safety design policy.

Scenario: A 6:1 fill slope exceeding 30 feet in height requires w-beam guardrail per the agency’s roadside design guide and AASHTO Roadside Design Guide criteria.

Data Flow:

  1. Safety engineer identifies warrant for guardrail based on slope and height
  2. Designer models guardrail along embankment with offset from edge
  3. Guardrail data exported with type, test level, and terminal treatments
  4. Construction documents include guardrail specifications and layout

Key Information Exchanged:

  • System: “W-beam guardrail (steel posts)”
  • Test level: TL-3 (MASH)
  • Post spacing: 6.25 feet
  • Offset from edge: 4 feet
  • Terminal: FLEAT (Flared Energy Absorbing Terminal)
  • Length: 850 feet