Laboratory Units - Special Tests Unit

Asphalt Products Lab

This laboratory tests the physical properties of asphalt cement, cutback asphalt, asphalt emulsion, polymerized asphalt, crack and joint fillers, flexible plastic gaskets, grease, oil, bituminous mixtures, roofing felt, anti-strip additives, antifreeze, and similar miscellaneous materials.

Typical properties tested are flash point, pour point, viscosity, specific gravity, ductility, rate of flow, percent absorption, percentage of residue, particle charge, penetration, softening point, bitumen content, Marshall stability and flow, and Abson recovery.

This laboratory has received a national accreditation by AMRL for asphalt cement, emulsified asphalt, and bituminous mixtures.

The Asphalt Products Lab is also responsible for maintaining the Department's AMLs for asphaltic materials, mineral filler for asphaltic concrete, anti-strip additives, asphalt mix release agents, flexible plastic gaskets, silicone additives for asphalt cement, and bituminous adhesive.

Geotextile, Rubber and Joint Materials Lab

This laboratory is responsible for the evaluation and testing of rubber products, such as elastomeric bearing pads, elastomeric compression seals, rubber gaskets, and similar miscellaneous materials. Typical properties tested are tensile strength, elongation, hardness, ozone resistance, oil swell, recovery, force deflection, extrusion, penetration, resilience, and compression/deflection.

This laboratory is also responsible for the evaluation and testing of geotextiles, geocomposites, and paper products. Geotextiles used for flexible revetment, riprap, underdrains, etc. are tested for properties such as apparent opening size (AOS), elongation, burst strength, permeability, etc. and paper products for basis weight, absorption rate, total absorption, and tensile strength. Traffic cones are occasionally tested for tensile strength, hardness, etc.

This laboratory is also responsible for maintaining the Department's AMLs on elastomeric bridge bearing pads, preformed elastomeric compression joint seals, geotextiles, elastomeric railroad grade crossings, and reinforced elastomeric joint seals.

Plastic Products Lab

This laboratory tests the physical properties of plastic pipe, thermoplastic striping material, joint sealants and fillers, plastic barrels, flexible posts, greases, and similar miscellaneous materials.

Typical properties tested are tensile strength, elongation, flattening, softening point, specific gravity, flow, bond strength, impact resistance, penetration, resilience, and hardness.

This laboratory is also responsible for maintaining the Department's AMLs on joint sealants and fillers, plastic drums, flexible posts, and thermoplastic pavement markings.

Traffic Control Products Lab

This laboratory tests the reflectance and physical properties of such materials as reflective sign sheeting, raised pavement markers, temporary pavement marking tape, reflectorized traffic striping paint, nonreflective signing material, and similar miscellaneous materials.

 

Tests run on reflective sheeting include visual tests such as color chromaticity, specular gloss, and specific intensity, and physical tests such as peel or adhesive strength, impact resistance, and flexibility. Tests run on raised pavement markers include reflectivity or brightness, load, impact, and heat resistance.

 

In addition, this laboratory conducts field evaluations of luminaires and reflective materials by means of portable field telephotometers and other instrumentation for appearance-type measurements. Outdoor weathering racks are maintained and monitored for testing the weatherability of sign sheeting.

 

This laboratory is responsible for maintaining the Department's AMLs for reflective sheeting, raised pavement markers, barricade warning lights, and temporary pavement markings.