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When a sinusoidal vibration was superimposed in parallel on the flow direction of a polymer melt being extruded through a capillary, the shear stress and shear rate of the polymer melt were analysed with a constant velocity type dynamic rheometer of capillary (CVDRC) devised by the authors. By measuring the instantaneous data of capillary entry pressure, capillary volume flux (or absolute velocity of piston rod) and their phase difference in a vibrating force field, it was found that the relationship between the pulsating amplitude value coefficient of entry pressure and that of volumetric flowrate was an approximate power series; the wall shear stress and wall shear rate of low density polyethylene (LDPE) melt extruded dynamically under various amplitudes and frequencies also exhibited a non-linear proportional relationship.

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To evaluate the effect of aging on asphalt self-healing performance, repeated shear tests on 70 # matrix asphalt and SBS modified asphalt aged through delayed rotating thin film oven test (RTFOT) are carried out under the stress control mode through dynamic shear rheological test (DSR). Intervals are drawn into the loading progress to make the self-healing phenomenon appear. The complex shear modulus of different ageing asphalt before and after healing is analyzed. The change ratio of complex shear modulus before and after healing (HI 1 ) and the ratio of complex modulus before and after loading (HI 2 ) are defined as selfhealing index of asphalt. These parameters are used to evaluate the self-healing property of asphalt. The results show that: the complex shear modulus of damaged asphalt can recover after self-healing thus the fatigue life is prolonged. The deeper the aging, the lower the self-healing ability of asphalt .The decrease rate of self-healing index with aging degree of 70 # matrix asphalt is greater than that of SBS modified asphalt. Compared with HI 2 , it is more reasonable to evaluate the self-healing property by HI 1 .1

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