4" & 6" JBR Tack Bond Shear Strength with Calibration Spring & Dial Indicator

The JBR Tack Bond Shear Strength Apparatus measures shear resistance at the interface between asphalt pavement layers bonded with tack coat. Designed for use with a compatible Marshall load frame, the jig includes adapters for testing 4-inch and 6-inch diameter cores.

Key Features

• Evaluates asphalt pavement interlayer tack-bond shear strength
• Heavy steel frame with fixed and moving shear plates
• Roller bearings help minimize sliding friction
• Moving plate aligned with the shear plane
• Calibrated spring and dial indicator regulate lateral specimen loading
• Adapters for 4-inch and 6-inch diameter pavement cores
• Fits compatible Marshall load frames with at least 10 inches of vertical clearance
• Shear plane gap: 0.5 inch; maximum shear travel: 0.5 inch

Included Items

JBR shear fixture, calibrated spring and dial indicator, plus adapters for 4-inch and 6-inch cores.

Lab Manager's Tip

Confirm at least 10 inches of load-frame daylight and verify the calibrated spring before testing. Tack-bond procedures often follow a state DOT or project-specific protocol, so document the required specimen temperature, loading rate and conditioning rather than assuming ASTM D6927 Marshall stability settings apply to this shear test.

Typical Applications

Tack coat evaluation, pavement interlayer shear testing, asphalt pavement research, DOT laboratory investigations and pavement rehabilitation QC.