锥形纳米管纵向振动固有频率

研究变截面锥形纳米管/棒的纵向振动问题。由于其控制方程涉及变系数微分方程,提出适用范围广、简单精确的积分方程方法求解该问题,基于经典弹性杆理论与非局部弹性杆理论分别给出几种边界条件下的固有频率计算。对一端固定一端附加集中质量的碳纳米管的纵向振动,给出共振基频的近似简单表达式。与其它方法所得数值结果对比表明该方法有效。     

金属矿山硐室发生岩爆的数学判据的研究

近年来,金属矿山发生岩爆的事故愈来愈多,对预测此类岩爆的发生也日益重要.通过对金属矿山岩爆的分析,建立了一种岩爆与临界深度有关的数学判据,以此来判别金属矿山硐室中是否有岩爆发生,并通过实例验证了其可行性,对有效预测预防金属矿山岩爆的发生具有一定的参考意义.     

Uniaxial tension and tensile creep behaviors of EPS

The mechanical behavior of EPS(Expanded polystyrene) with three densities at room temperature and under tension loading was studied.The results show that EPS material is characterized by brittle behavior in the tension tests,and tensile properties of EPS increase with the increase of density.Volume fraction has no a significant effect on the modulus of these foams.The tensile creep strain increases with stress for EPS with same density,indicating that the creep behavior is of the stress dependency.And the creep behavior of EPS exhibits density dependency,which the creep strain decreases with densities for a fixed stress value.Moreover the creep behavior under the constant tension load is well in coincidence with the three-parameter solid model.