How does an asphalt binder tester work?

The asphalt binder tester has long been involved in the improvement of AASHTO and industry standards. For example, the asphalt binder tester incorporates new and innovative procedures, such as core-cylindrical geometry, to evaluate new materials such as ground tire rubber modified adhesives (modified adhesives).

This article includes 3 parts:

1.Collecting test data using traditional and advanced test equipment

2. A measurement system 

3. Evaluate the performance of asphalt binders

1. Collecting test data using traditional and advanced test equipment

The asphalt binder tester focuses on collecting test data using traditional and advanced test equipment to evaluate test repeatability and improve the test process. The durability of asphalt pavement is largely affected by the properties of the asphalt binder. Our state-of-the-art laboratory is AASHTO resource certified, capable of characterizing the performance of asphalt binders over a wide temperature range. The asphalt binder tester uses a dynamic shear rheometer to evaluate the characteristics of the adhesive at high and moderate temperatures, while using a curved beam rheometer, a direct tensile test, and an asphalt binder cracking device to study the low temperature of the binder cracking properties.

2. A measurement system 

The asphalt binder tester device consists of a measurement system, an environmental chamber, a loading device, a control and data acquisition system. Asphalt binder tester is an asphalt binder used to determine complex shear modulus (G *) and phase angle (δ). The results of these rheological tests provide a measure of the rut and fatigue resistance of asphalt binders, and the asphalt binders are classified according to the AASHTO m320 standard. The asphalt binder tester device is also used in a multiple stress creep recovery (MSCR) test (AASHTO t350) to determine the performance level of a modified asphalt binder (AASHTO m332).

3. Evaluate the performance of asphalt binders

In order to evaluate the performance of asphalt binders over a range of temperatures and loading rates, the asphalt binder tester also performed a master curve characterization. They are constructed from an asphalt binder tester using frequency-scan data collected using time-temperature superposition at a variety of temperatures and loading rates. This gives agencies and contractors a better understanding of the effects of climate and transportation on site adhesive performance.

The asphalt binder tester was used to determine the thermal cracking temperature of the asphalt binder. Thermal stress and breaking strength can be determined from strain readings. The device is designed for testing in the -60 to + 20 ° C range. The asphalt binder tester measured the temperature and strain of the bound asphalt binder ring under constant cooling rate. The asphalt binder sample was heated and poured out of an Invar ring placed in the center of a silicone mold. The Invar ring includes a strain gauge to record the strain caused by the shrinkage of the asphalt binder during cooling and a resistance temperature probe to record the temperature. The sample was cooled at a constant rate, and cracking of the asphalt binder appeared as a jump in strain on the real-time map. The strain jump was recorded and the fracture stress was measured at the cracking temperature. Full details of the asphalt binder tester test method are given in the AASHTO TP 92 test method.