Compact tension geometry

A limited number of KIC values were obtained with a compact tension geometry for which KIC is calculated with Eq. (3)... 

Finally, the fracture energy, Gf, of asphalt-aggregate mixtures using the disc-shaped compact tension geometry may also be used to describe the fracture resistance of asphalt concrete. The test is performed in accordance to ASTM D 7313 (2013) specifications. 

Determination of fracture energy of asphalt-aggregate mixtures using the disc-shaped compact tension geometry... 

For the important compact tension geometry (Fig. 12c), K is generally expressed in terms of the applied load P ... 

The fracture toughness results presented thus far were derived from a fairly small 3PB specimen. In limited work with a proportionately larger 3PB sample (B 6.4 mm), a similar K1C value was found for the control. A second geometry, compact tension (CT), was utilized for alternate determinations of K,c. The K t values found with the CT specimens agreed within error with those obtained with the 3PB geometry, as shown in Table 4. 

Fig. 9 Specimen geometries for fracture measurements a compact-tension, b three-point bending...

Specimen geometry for the compact-tension (CT) test is shown in Fig. 9a. 

A quantitative approach to the reinforcement of interfaces with block copolymers is necessary. Such an approach requires a way to evaluate the strength of the interface separately from any change in the morphology or microstructure of the blend. While classic fracture mechanics tests such as compact tension and double torsion could be used, the asymmetric double cantilever beam (ADCB) test used in the first such study [17] has been adopted by all successive workers to date. In this experimental geometry, shown schematically in Fig. 3, a wedge (usually a razor blade) is inserted at the interface. In some versions of the test the... 

Fracture toughness tests for isotropic materials normally use edge-notched flexure beams and compact tension specimens. These methods are. as for the impact tests, only suitable for the injected or compression molded materials, which do not have a strongly laminated structure. Laminated composite materials have their primary failure path between the layers, and a new set of test geometries has been developed. 

Alternative geometries and test methods to determine the fracture toughness of ceramics and hard materials have been developed over the last decades Herzian indentation [88], the double torsion test [89], and compact tension tests [90 92]. 

Specimen geometries used to determine K,c (a) compact tension (Cll specimen and (b) single-edge-notched bend (SENS) specimen. 

In treating adhesives as polymeric materials, it is possible to use Fracture-mechanics test specimens to determine material properties independent of geometry. A typical sample would be the compact tension test-piece, where a sheet of material, typically 6-mm thick and 100-mm square, has a sharp crack inserted in one edge. The sample is then loaded perpendicular to the plane of the crack and the load at which crack propagation... 

Fig. 12. Testing geometries (a) single-edge notch tension (SENT), (b) single-edge notch three-point bending (SEND), and (c) compact tension (CT).

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