No abstract

In order to resolve the outstanding problem of China on how to scientifically manage and maintain airfield runway on highway, and according to realistic situation of prevailing of asphalt pavement, as well as transit characteristics of automobile and airplane on airfield runway on highway, the performance of asphalt pavement is analyzed via the aspects of bearing capability, high temperature stability, low temperature anti-cracking property, durability, smoothness, anti-sliding performance, drainability, etc, to qualitatively propose the requirements; in order to provide reference for utilization and management, to effectively and properly evaluate the asphalt pavement, the evaluation system is proposed, and its main index includes pavement bearing strength, appearance quality, friction coefficient, and evenness, etc.

To realize the color functionalization of road paving, this paper developed a light-colored resin modified asphalt, which can be added with toner to adjust different colors to realize the color paving of asphalt mixture. Fourier infrared spectroscopy (FT-IR) was used to analyze the difference between functional group composition of light-colored asphalt and 70# petroleum asphalt and to compare the conventional performance and road performance of light-colored asphalt with I-D grade modified asphalt. The road performance mainly includes high temperature performance, water stability performance and anti-skid performance. The test results showed that the light-colored asphalt and 70# petroleum asphalt had similar functional group composition, and the technical indicators of the light-colored asphalt could meet the requirements of I-D grade modified asphalt; the three road performances of the light-colored asphalt mixture met the specification requirements, which were even more excellent than the I-D grade modified asphalt mixture, indicating that the light-colored resin modified asphalt synthesized in this paper can meet the application of road engineering. Meanwhile, the light-colored resin modified asphalt has less smoke, lower carbon emissions, and superior performance than petroleum asphalt during use, which is beneficial to the sustainable development of road engineering.

The viscoelastic Poisson's ratio of solid propellant seriously affects the analytical accuracy of the structural integrity of the solid rocket motor. Based on the digital image correlation (DIC) method, a stress relaxation test and a uniaxial constant tensile rate test were carried out to measure the viscoelastic Poisson's ratio of the composite solid propellant according to the stress characteristics of solidification cooling and ignition pressurization conditions. The effects of time, temperature, longitudinal strain as well as tensile rate on the viscoelastic Poisson's ratio of propellant were studied. In this paper, the main curves of the temperature and strain rate of the propellant Poisson's ratio at the reference temperature of 25 °C and the main curves of temperature and longitudinal strain at the reference time of 10000 s were established. The research shows that the viscoelastic Poisson's ratio of composite solid propellants increased with increasing temperature, longitudinal strain and tensile rate. Under the solidification cooling condition, the Poisson's ratio of the solid propellant does not change significantly with time. At this point, the Poisson's ratio can be regarded as a constant, but the appropriate value must be selected according to the operating temperature and initial deformation of the solid rocket motor. In the uniaxial constant tensile rate test, when the stretching rate reached 500 mm/min, Poisson's ratio of the propellant gradually approached a certain constant value. Considering that the loading rate of the propellant is generally above 0.5 s−1 under the ignition pressurization condition, the strain rate is large, the Poisson's ratio of the propellant can be taken as a constant. Relevant methods and conclusions can provide a reference for structural analysis and storage life prediction of solid rocket motors.