In order to obtain the seismic dynamic characteristics of a shallow-bias tunnel with a small space, a series of large-scale shaking table model tests were carried out. The key technology of the test is introduced in detail, for example, similar ratios of model, test equipment, testing model box, testing model, sensor arrangement, seismic waves, and testing system. The results show that the first predominant frequency is similar between measuring points. However, the second predominant frequency is highly different between measuring points. The first and second predominant frequencies gradually decrease with the increasing of input PGA. The rock stratum can shield seismic wave in the high frequency band. The research results provide reference for similar tunnels.

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Dynamic vulcanization was successfully applied to epoxy resin reinforced polypropylene (PP)/ethylene-octene copolymer (POE) blends, and the effects of different compatibilizers on the morphology and properties of dynamically cured PP/POE/epoxy blends were studied. The results show that dynamically cured PP/ POE/epoxy blends compatibilized with maleic anhydridegrafted polypropylene (MAH-g-PP) have a three-phase structure consisting of POE and epoxy particles dispersed in the PP continuous phase, and these blends had improved tensile strength and flexural modulus. While using maleic anhydride-grafted POE (MAH-g-POE) as a compatibilizer, the structure of the core-shell complex phase and the PP continuous phase showed that epoxy particles could be embedded in MAH-g-POE in the blends, and gave rise to an increase in impact strength, while retaining a certain strength and modulus. DSC analysis showed that the epoxy particles in the blends compatibilized with MAH-g-PP were more efficient nucleating agents for PP than they were in the blends compatibilized with MAH-g-POE. WAXD analysis shows that compatibilization do not disturb the crystalline structure of PP in the blends.

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