AASHTO T 370:2018 Standard Method of Test for Measuring Adhesion of Hot-Poured Asphalt Crack Sealant Using Direct Adhesion Tester.
3.1.2. hot-poured asphalt crack sealant—hot-poured modified asphaltic material used in pavement cracks and joints.
Note 1 Based on the references, hot-poured asphalt crack sealant is typically applied at a temperature of 160°C or above.
4.1. Hot-poured asphalt crack sealant material is homogenized, following the procedure given in ASTM D5l67. For each test including four replicates, cut 40 g of sealant and heat to the manufacturer’s recommended pouring temperature. Sealant will be poured in the mold placed between the two half-cylindrical aluminum end pieces. The mold confines the sealant at the bottom and between the two aluminum end pieces at the sides.
5.1. This procedure is designed to measure the adhesion of hot-poured asphalt crack sealant to aggregate.
5.2. Hot-poured asphalt crack sealant must be homogenized (ASTM D5 167) before measuring the adhesion by this method.
6.1. Direct Tension Test (DTT) Device—The DTT system consists of two metal grips to hold the specimen, an environment chamber, a loading device, and a control and data acquisition system. The instrument must meet the requirements stated in T 314.
6.2. Test Chamber—A calibrated circulated temperature control system having a temperature range from —4 to —40°C. The insulated test chamber shall be capable of maintaining the set temperature within ± 0.1°C.
6.3. Laboratory Oven—Any standard laboratory oven capable of producing and maintaining temperatures ranging up to 200°C ± 2°C.
6.4. Release Agent—A proper release agent to prevent the crack sealant from sticking to the mold. A silicon-based release agent is recommended.
6.5. Specimen Molds—Specimen molds shall be made of aluminum Al-606l with No. 32 grid interface surfaces. The aluminum molds shall have pieces and dimensions as shown in Figure 1.
Note 2—Mold interface is manufactured to No. 32 grid. It is recommended to perform a visual examination of the interface surfaces before every test for dents, scratches, or bents. If the interface is visually deteriorated, replacement of the mold is recommended.AASHTO T 370 pdf download.