Asphalt Dynamic Modulus Testing via Impact Load Stamp

The patent extracts only the essential measurement function from the complex laboratory splitting tension-swelling test. By using a simple drop weight applied through a circular stamp to create a stress bulb in the asphalt, it isolates the key parameter (dynamic elastic modulus) measurement from the time-consuming and destructive full laboratory testing procedure, enabling rapid field testing while maintaining measurement accuracy.

The patent creates a simplified field test version that copies the essential measurement principle of the laboratory test. Instead of performing the complete splitting tension-swelling test in the laboratory, it uses a scaled-down drop weight impact method that replicates the core measurement function, allowing results to be obtained immediately in the field without sampling and laboratory processing delays.

The patent concentrates the loading into a small circular stamp area (10-50 mm diameter), creating a localized stress bulb that affects only a limited volume of asphalt directly beneath the stamp. This localized approach obtains accurate dynamic elastic modulus measurements while minimizing the affected area and preventing the widespread permanent damage caused by removing cylindrical test specimens in the traditional method.

The patent uses a dynamic impact load (drop weight) applied in a single brief moment rather than continuous loading. This periodic impact action determines the dynamic elastic modulus immediately without requiring prolonged testing that would cause progressive damage and eventual fracture of the asphalt surface, thus preserving the tested area.

The patent uses a small diameter circular stamp (10-50 mm) to concentrate the load into a localized stress bulb that primarily affects the asphalt layer. This localized stress distribution ensures that the measured dynamic elastic modulus reflects the asphalt material properties rather than the combined response of the entire pavement structure, while still enabling field testing operation.

The patent changes the loading parameters by using a controlled drop weight impact through a small circular stamp, creating a specific stress distribution pattern that penetrates the asphalt layer. By adjusting the stamp diameter and drop height, the stress bulb is confined to the asphalt material, allowing field testing while obtaining accurate asphalt-specific material parameters rather than overall structural response.