scope:

This draft European Standard specifies test methods for determining the bond strength between an asphalt layer and other construction layers in road or airfield pavement. The tests can also be applied on laboratory prepared interlayers. Further informative test methods are defined for evaluating the complex bond stiffness between road construction layers. The normative tests described in this standard are ? Torque bond test (TBT), ? Shear bond test (SBT), ? Tensile Adhesion Test (TAT). Further two test methods for evaluating the complex bond stiffness are described in informative annexes: ? Compressed shear bond test (CSBT), ? Cyclic compressed shear bond test (CCSBT). NOTE The described test methods simulate different loading conditions and are applicable on different bonds between road construction layers: The torque bond test assesses the resistance to horizontal shear stress: ? The torque bond test is suitable for testing the bond strength between road layers in laboratory and in situ. ? The torque bond test assesses the resistance to the stresses generated primarily by traffic accelerating or braking, but also by thermal movements when the layers are of different materials (e.g. asphalt, microsurfacing or cement concrete) ? The torque bond test can be carried out immediately after laying. ? The torque bond test can be applied for assess the capability of bond coats or tack coats. ? When the thickness of the top layer above the interlayer assessed is less than 15 mm, the torque bond test can be applied for evaluating the durability of the top layer. The shear bond test assesses the resistance to horizontal shear stresses in the interlayer of two road construction layers. ? The shear bond test assesses the resistance to the stresses generated primarily by traffic accelerating or braking, but also by thermal movements when the layers are of different materials (e.g. asphalt, microsurfacing or cement concrete). ? The shear bond test can be appl ...