In order to improve the correctness of vibration intensity prediction in a tunnel' s fieldnear blasting,a calculation model for the vibration velocity of the field was established based on the assumption of the linear superposition theory.Based on the measured vibration data in Beijing' s Xing-yan highway tunnel within the mileage range of YK28 + 190 to YK28 + 354,the feasibility of the calculation model was verified,the vibration law of the tunnel' s field near blasting was studied.The results showedthat ① the blasting vibration prediction model based on the waveform superposition is suitable for the near field vibration prediction;② in the direction of the tunnel cross-section parallel to the tunnel face,with increase in a single-hole charge,the energy density of each tunnel cross-section increases,the intensity of vibration velocity contour sincreases;the vibration velocity growing rate of the central measuring line is larger than those of both sides,this phenomenon is specially obvious in blasting near area;on the measuring line perpendicular to the tunnel face,the vibration velocity attenuation speed decreases gradually with increase in the distance from blasting source;③ with increase in the number of cut holes,the vibration velocity contours shift outwards and become flat gradually;in the direction of the tunnel cross-section parallel to the tunnel face,the vibration velocity growing rate decreases gradually.%为了改善隧道近区振动强度预测的准确性,以线性叠加理论的假设条件为基础,建立了符合现场实际的隧道近区振速计算模型.以北京兴延高速公道浇花峪右线隧道,里程为YK28+ 190到YK28+ 354范围内实测数据验证模型的可行性,并对隧道近区振动规律进行研究.研究表明:①基于波形叠加的爆破振动预测模型适用于隧道近区振动预测;②随着单孔装药量的增加,平行于掌子面的隧道截面上能量密度增加,振速等值线的强度增大,轮廓形态出现变化,中心测线振速的增长幅度大于两边,在爆破近区这种现象尤为明显;隧道已开挖区垂直掌子面的测线方向上,随着离爆源的距离增加,振速的衰减速度逐渐变小.③随掏槽孔孔数目的增多,相同数值的等值线外移,且等值线逐渐平缓;平行于掌子面的隧道截面上,振速的增加幅度逐渐减小.
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