| About 75% of our territory are mountains or hills. With the development of higway, the scale of mountain highway tunnels have expanded gradually. Construction of highway tunnels is the developing trend of eliminating road diseas in the future.By extracting document information, enunciated the state of ground vibration effect caused by dig blast and problems; expounded fundamental theory of underground egineering blasting excavation; on the base of the field test of blasting vibration of long-span neighborhood Qilinshan highway tunnels, and there is a 110kV electric tower on the surface. A program has been designed by myself, application of Matlab7.1 in field data linear regression analysis. This paper mainly analysis the propagation law of blast-caused seismic wave. Unicorn Mountain Tunnel by blasting holes and the formation of cavities is not only the formation of different priorities, choose the left lane on the left pilot tunnel has been excavated, the left hand lane on the right pilot tunnel is excavated, the rest of the excavation of the special conditions not In cross-sectional layout of measurement points for surface blasting vibration field test. Mainly by the following results:(1) Satisfies the premise of tunnel blasting results, bursting through the cutting area to reduce sub-paragraph charge the maximum amount of vibration can be greatly reduced strength, damping ratio before and after the maximum vibration velocity; obtained through discussions, cutting areas, check avalanche The surrounding area were blasting blasting vibration may cause the maximum speed burst cutting area does not necessarily lead to the maximum shock strength, shock strength and the free surface of situations in addition to, but also with the loading dose and other factors.(2) Above the blasting holes with vibration amplification and more distant from the explosion source, with the empty side of the vibration reducing effect. Horizontal distance of 12m away from the explosion source above the surface at the hollow point, the maximum vibration velocity is measured there is no hole symmetric point of the surface measured 1.50～1.60 times the horizontal distance of 24m away from the explosion source, there is an empty side of the surface at the point of maximum vibration velocity is measured is not symmetrical there is an empty surface measurement points 0.54 to 0.71 times. There is an empty lot does not meet the SA Road Cliffs attenuation given by the formula, there is an empty lot can be used instead of SA Road Hargreaves formula for strength prediction, and there is an empty surface vibration velocity measuring point there is no hole symmetry than the measuring point, which meant that the upper hole with amplification of ground vibrations, and far away from the hole in the side explosive source of vibration measuring point faster than the measuring point does not exist a small hole symmetry, indicating that hole with a cut-off wave damping effect.(3) Were selected empirical formula Sa Road, Ostrovsky, the revised formula commonly used in Japan, the United States Bureau of Mines attenuation of empirical formula described in the blasting, and comparative analysis of empirical formula that Sa Road, Ostrovsky and modified formula can be well used in Japan empty lot description does not exist wave propagation of ground vibrations, the linear correlation coefficient reached 0.98, while the U.S. Bureau of Mines empirical formula described only when the linear correlation coefficient of 0.83. The test data into an empty lot there is no data of surface measurement points, there are empty lots, empty and there is no data of surface measurement points, there are empty lots of data three types of surface measurement points, using three empirical data on three types of linear regression, the results show that the first category correlation coefficient of linear regression the largest linear correlation coefficient of the second class data second, third type of data the minimum correlation coefficient of linear regression.The empty effect applied to engineering practice, draw two of the Qilin mountain tunnel and its security and stability of the tower on the cover of the two suggestions:1 Qilin mountain tunnel are advised to left lane on the left pilot tunnel excavation to form a hollow, right lane, left lane on the right due to the existence of pilot tunnel blasting holes, the direction of K16+465 import left hand lane at about 3.5m Proximity overlying the tower Department has reduced vibration effects, is conducive to security and stability of the tower:2 Qilin mountain tunnel middle pillar thickness of only 4.7m, when the right line on the left guide hole blasting, because the left lane on the right pilot tunnel has been excavated, the left hand lane on the right wall of the left and right line of the explosion source Jinju 4.7m, on the one hand, blasting vibration has a direct impact strength and distance, the smaller the distance, the greater the vibration intensity; the other hand, blasting a hole just above the amplification effect, suggesting that the left side of guide hole blasting right line, the left lane right side of the wall to the vibration speed is greater than the symmetric point explosion source, there is no empty lots in the vibration velocity. Kirin Tunnel Right Line drawn on the left before the excavation of pilot tunnel left line blasting should be finalized by the second lining to meet the design strength of construction and lining, will benefit the left tunnel on the right wall of the security and stability.
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