Abstract: The present disclosure provides a detection and analysis method for rapid delineation of aging stages of styrene-butadiene-styrene (SBS) modified asphalt, including the following steps: performing a Fourier transform infrared spectroscopy (FTIR) test on unaged SBS-modified asphalt samples to obtain a copolymer index of IB0/S0 and neat asphalt functional group indexes, including the SI0, IB, aI0, ARI0, and CI0; performing the FTIR test on the aged SBS-modified asphalt samples to obtain an actual index of IB/S, SI, IB, aI, ARI, and CI; and delineating three aging stages of SBS-modified asphalt, including a polymer swelling stage, a polymer degradation stage and a component imbalance stage according to changes of functional group indexes. According to the present disclosure, the actual aging stages of the SBS-modified asphalt can be determined rapidly and accurately, providing a reasonable basis for the decision on pavement maintenance timing and mode.

Abstract: The present disclosure provides a detection and analysis method for rapid delineation of aging stages of styrene-butadiene-styrene (SBS) modified asphalt, including the following steps: performing a Fourier transform infrared spectroscopy (FTIR) test on unaged SBS-modified asphalt samples to obtain a copolymer index of IB0/S0 and neat asphalt functional group indexes, including the SI0, IB, aI0, ARI0, and CI0; performing the FTIR test on the aged SBS-modified asphalt samples to obtain an actual index of IB/S, SI, IB, aI, ARI, and CI; and delineating three aging stages of SBS-modified asphalt, including a polymer swelling stage, a polymer degradation stage and a component imbalance stage according to changes of functional group indexes. According to the present disclosure, the actual aging stages of the SBS-modified asphalt can be determined rapidly and accurately, providing a reasonable basis for the decision on pavement maintenance timing and mode.

Abstract: A light-emitting diode which emits light uniformly emitted all around is provided. The present invention comprises a light emitting diode (LED) die, a transparent envelop body and a connection pin, which is characterized in that the envelop body is a cylindrical body and a top surface of the envelop body being indented to form a semi-spherical recess or, a conic concave or a polygonal concave with a tip angle between 100° to 140°. Since the present invention uses a structure which the top of the envelop body is disposed as a inward concave shape with the tip angle between 100° to 140° or semi-spherical recess shape, it skillfully makes use of the optical spreading characteristic of the inward concave body. Which makes light beam which is emitted by the light emitting diode die emit uniformly all around the envelop body via refraction of a plurality of the sides of the inward concave body. At the same time, in order to further enhance its decorative, said envelop body is set to different colour coloured body.