在杂填土坡地和平坦场地中对比分析了4000kN·m、12000kN·m、25000kN·m能级下振源距、夯击能、夯沉量3种独立因素对振动速度的影响规律,在此基础上,结合Bp神经网络与Sobol敏感性分析法分析了上述3种因素对振动速度影响的强弱。结果表明：坡地场地中振动速度在坡肩～坡底范围内符合负指数函数关系,坡肩存在“能量集中”效应,坡肩的振动速度大于相同振源距的平坦场地；杂填土边坡中振动速度大多介于4~25 mm/s之间,振动速度与夯击能之间符合负指数函数关系,夯击能对振动速度的影响有限；随着夯沉量的增大,振动速度增长先快后慢,最终趋于稳定,在累计夯沉量-夯沉量曲线的“下凹”折点后,振动速度增长或增长率增大,在“上凸”型折点后,振动速度减小或增长率衰减。夯沉量对振动速度的全效应敏感性指数为振源距的1.55 倍、夯击能的 5.93 倍,减小夯沉量对减轻振动的效果最明显,振源距次之,夯击能最小。

The influence of three independent factors, i.e.vibration source distance, tamping energy and tamping settlement, on the vibration velocity under the energy levels of 4000kN · m, 12000kN · m and 25000kN · m was compared and analyzed in the miscellaneous fill slope and flat site. On this basis, the Bp neural network and Sobol sensitivity analysis method were used to analyze the influence of the above three factors on the vibration velocity. The results indicate that in slope sites, vibration velocity follows a negative exponential relationship from the slope’s shoulder to its base. An "energy concentration" effect is observed at the slope's shoulder, where the vibration velocity is higher than that of flat sites at the same source distance. In miscellaneous fill slopes, vibration velocity mostly ranges between 4 and 25 mm/s, and though it also follows a negative exponential relationship with impact energy, the effect of energy on vibration velocity is limited. As tamping settlement increases, vibration velocity initially rises rapidly, then slows, eventually stabilizing. After reaching a "concave" inflection point on the cumulative tamping curve, the velocity increases or the growth rate accelerates; beyond a "convex" inflection point, the velocity decreases or the growth rate slows. Sensitivity analysis shows that tamping settlement has the greatest influence on vibration velocity, being 1.55 times more significant than source distance and 5.93 times more significant than tamping energy. Reducing tamping settlement is the most effective way to lower vibration, followed by increasing source distance, with tamping energy having the smallest effect.

TU441.4

国家自然科学基金项目（42277151、42307277)；陕西省秦创原“科学家+工程师”团队建设项目(2022KXJ-086)