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This paper presents a dynamic model of asphalt pavement by considering the characteristics of moving tyre load, viscoelastic performance of material and layered system of pavement. The pavement is defined as an infinite layered system with the tyre load moving at a constant speed, and asphalt concrete (AC) is characterised as a kind of visco-elastic material. Using the spectrum analysis method, a complex tyre load is decomposed into a series of harmonic loads. Based on the frequency characteristics of a linear system, a universal formulation pattern for differential visco-elastic constitutive relations is provided. And then, a model is set up to analyse the dynamic response of asphalt pavement under moving harmonic load, and then to extend to the arbitrary moving load according to the superposition principle of a linear system. The dynamic responses of seven typical semi-rigid base asphalt pavements are analysed using the model. Analysis results indicate that the tensional strain at the bottom of the AC layer and the vertical compression strain at the top of the roadbed are not suitable for key indices of the semi-rigid base asphalt pavement. The shearing strain at the bottom of the AC layer can be taken as a key index to evaluate the fatigue performance, and the vertical compression strain at the top of the pavement surface can be taken as a key index to evaluate pavement rutting, and the vertical shearing strain at the top of pavement surface can be taken as a key index to evaluate top-down crack.

Suction cups of cephalopods show a preeminent performance when absorbing irregular or flat objects. In this paper, an octopi-inspired suction cup, driven by hydraulically coupled dielectric elastomer actuators (HCDEAs), is proposed, which is considered to be controlled easily and have compact structure. To investigate the performance of suction cups, experiments have been conducted to clarify the effect of the pre-stretch ratio and chamber angle on suction forces. It could be seen that both factors have a complicated influence on suction forces, and the best performance obtained was a reasonable combination of the pre-stretch ratio and chamber angle. Here, we achieved a maximum suction force of 175 mN with λp = 1.2, α = 23° under a DC voltage of 3500 V. To enhance the capacity and adaptation of the suction cup, flat objects of various types of materials were introduced as targets. Experimental results displayed that for tested materials, including a dry/wet acrylic plate, CD, ceramic wafer, and aluminum plate, the suction cup showed outstanding performance of absorbing and lifting the target without any damage or scratch to them. Our research may serve as a guide to the optimal design and provide insights into the performance of the HCDEAs-actuated suction cup.

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The three-dimensional modeling and analysis of virtual pavement are conducted for the complex and diverse test pavements in the vehicle reliability driving test. Firstly, a complete pavement unevenness acquisition system is constructed, and secondly, the classification and processing methods of different pavements are determined according to the actual working conditions and load spectrum data of the test pavement in the test site to provide a theoretical basis for the virtual pavement modeling. At the same time, considering that the test pavement also includes various complex pavement conditions such as curves, slopes and lateral inclination, the structural composition and differences of plane curves, longitudinal ramps and cross-sections are analyzed to provide a guarantee for the further establishment of an accurate 3D pavement model. Finally, the 3D virtual pavement model of typical test pavements is established according to the theory and methods of the above research, and the accuracy of random pavement reconstruction is analyzed, which provides accurate and effective technical support for the simulation of automobile reliability driving tests.