The Semi-Circular Bend (SCB) Test Fixture is used to calculate the fracture energy of asphalt mixtures (maximum aggregate size of 19mm) from a load-displacement curve. Semicircular samples are cut from Superpave Gyratory compacted cylinders or 150mm field cores.

The SCB Test Fixture consists of a 0.5in (12.7mm) thick steel base plate, two L-shaped roller support steel blocks, two steel rollers, a loading ball, and a U-shaped frame. The test fixture is mounted for loading in a Marshall Stability Testers.

A specimen is positioned with the flat side on two rollers, and a load is applied along the vertical diameter of the specimen. Load and displacement are measured to calculate test results. The initial roller position is maintained by soft springs and backstops, which establish the test span dimension.

Features:

Determines fracture energy and toughness of asphalt mixtures
Mounts in most standard Marshall Stability Load Frames
Test specimens are easily prepared from molded Superpave Gyratory samples or from 150mm field cores

Included Items:

Semi-Circular Bend Test Fixture
Loading ball

Accessories:

MSA-41 Teflon Tape, 1in x 108ft, can be used with the SCB fixture to reduce the friction between the asphalt specimen and lower support rollers

Specifications

Attribute name	Attribute value
Product Dimensions	6.25 x 5 x 8.4in (159 x 127 x 213mm) WxDxH
Estimated Shipping Weight	14.0lb (6.35kg)

Product Q&A

Q: How are longer specimens extracted and the piston returned?

Specimens longer than 5in are extracted by repositioning the Adapter Ring after maximum piston travel, and the spring-loaded piston automatically returns to the start position when the release valve is opened.

Q: What is the purpose of the Semi-Circular Bend (SCB) Test Fixture?

It is used to calculate the fracture energy of asphalt mixtures with a maximum aggregate size of 19mm from a load-displacement curve, utilizing semicircular samples cut from Superpave Gyratory compacted cylinders or 150mm field cores.

Q: What are the structural components of the SCB Test Fixture?

It consists of a 0.5in (12.7mm) thick steel base plate, two L-shaped roller support steel blocks, two steel rollers, a loading ball, and a U-shaped frame.

Q: How is the test procedure performed using the SCB fixture?

The test fixture is mounted in Marshall Stability Testers, a specimen is positioned with the flat side on two rollers, and a load is applied along the vertical diameter while load and displacement are measured, with the initial roller position maintained by soft springs and backstops establishing the test span dimension.