The flexible stress sensitive conductive polymer composites (CPCs) have a wide application prospect in the fields of the wearable human machine interaction, the medical monitoring, the portable sports equipment and the bionic robot, and others. The conductive percolation theory, the response mechanisms and the sensitivity of the stress sensitive CPCs are discussed in this paper. The response characteristics of different types of stress sensitive CPCs are reviewed, including the numerical predications. Finally, the future development is commented.
The influence of the cross section on the initial compression wave is studied by using the moving model experiment in this paper. The results show that the initial compression wave variation is the combined result of the average cross-sectional area and the cross-sectional area distribution of a high-speed train streamlined nose when the train's max cross section and the streamlined nose length are the same. The average cross-sectional area affects the magnitude of the initial compression wave, and the cross-sectional area distribution affects the pressure gradient of the initial compression wave, therefore, affects the pressure dissipation of the initial compression wave propagating in the tunnel.
The influence of the surrounding rock weight on the rock stress around a shallow buried pipe can not be neglected. Based on the solution method proposed by Verruijt, with both the deadweight and the internal pressure considered, the surrounding rock stress in a semi-infinite region with a circular cavity is studied. The analytical solution of this problem by using complex functions, conformal mapping and Fourier transforms is obtained. The influence of the internal pressure and the radius and the ratio of the radius to the depth on the stress of the surrounding rock with consideration of the internal pressure and the deadweight is analyzed, which provides a theoretical basis for the pipeline design and the construction safety.