The content SBS plays an important role on the performances of its modified asphalt. Traditional methods which were based on the differences of performances and molecular weight couldn’t quantify SBS content accurately. On the basis of FTIR analysis of SBS, the characteristic peak combination of modified asphalt that could be possibly used for quantitative analysis was summarized. According to theory of Lambert-Beer’s law, a relationship of absorbance ratio and content of mass was deduced. Considering the physical property of SBS polymer modified asphalt and coefficient of variation of specimens, the standard method to prepare SBS polymer modified asphalt for FTIR test was established. Then, regression coefficients were tested for significances combining with theoretical equation and linear programming method, the optimum characteristic peak ratio combination for quantification was designated. Finally, a reasonably accurate and precise method to quantify SBS content is achieved, and the author expected the research could provide the guidance for quantification of polymer content in polymer modified asphalt through this paper.

Based on the mechanics characteristics of partially earth-anchored cable-stayed bridge, the criterion of reasonable finished dead state was presented. The effect factors considered include: the distribution of cable force, the inner force of girder and tower, the dimension of earth-anchor, and the displacement of tower top. Combined with methods to determine cable force of traditional self-anchored cable-stayed bridges in reasonable completed status, a two-stage method was used to find the cable force of these bridges which was divided into finding the initial cable force with rigid supported continuous beam method and then fix on the final optimized cable force in the reasonable completed status through adjusting the initial cable force in first stage with influence matrix method. And the adjustment process of cable force in secondary stage was proposed based on the mechanics characteristics of these bridges. Finally, a calculation was carried out for a partially earth-anchored cable-stayed bridge with 1218m main span and composite beam. The result shows that this method was logical, practical convenient and efficient. And the cable force in the reasonable completed status of bridges can be obtained faster according to the adjustment process of cable force in secondary stage.

With the current development of hot stamping technology, quality products have been striving for not only uniformity in hardness but also a minimum of springback. Considering the fact that the uniformity distribution of hardness and the randomness distribution of the springback are inevitable in hot stamping process due to many complex factors such as contact sequence, contact clearance, scale and initial stamping temperature, a new method named RCP method was proposed to improve the hardness and springback of hot stamping product in this paper. The cooling rate control before stamping is applied based on CCT curves through a rapid air cooling device which can provide cooling rate of 60°C/s. Three parameters included initial stamping temperature, contacting pressure and dwelling time have been investigated in this paper. According to the experiment results, the hardness deviation is markedly decreased and the springback can be controlled within the threshold value ±0.5mm.

In order to analyze the residual mechanical properties of concrete frame structures after fire, a novel numerical model considering the distribution of non-uniform temperature in the cross-sections of structural members and the changing of mechanical properties of materials damaged by fire is developed in this paper by dividing the cross-sections of structural members into a lot of concrete fibers and steel fibers based on the concept of fiber model. Besides, the Analytical System of Fire-damaged Concrete Frame (ASFCF) is established through the secondary development of ABAQUS Software that is completed by the programming language of Python. This system is used to analyze the temperature fields and the nonlinear mechanical performances of a multi-story, multi-span, three-dimensional concrete frame after fire. The results indicate that ASFCF can properly analyze the mechanical properties of concrete frames after fire, and it provides valuable references for assessing the residual mechanical properties of concrete frames after fire.

A two-dimensional modified cellular automaton (CA) model was developed to simulate the dynamic recrystallization (DRX) behaviour during thermo-mechanical processing. It provides a link for multiscale modeling to bridge the mesoscopic dislocation activities with the macroscopic mechanical properties. This model is applied to investigate the effect of initial grain sizes on DRX process in commercial pure copper. The simulated results indicate that the stable size of recrystallized grain is independent on initial grain sizes. However, the percentage of DRX is not only related to the thermo-mechanical parameters, but also influenced by the initial microstructure. It is concluded that larger initial grain sizes promote a delay in the DRX occur on commercial pure copper. The calculated results compare well with the limited number of experimental observations and theoretical conclusions.