The application of drilling and blasting technology in long urban cross-ridge tunnels can effectively improve construction efficiency and save the costs.However,due to the surrounding environment of urban tunnel,the harmful effects of blasting are becoming more and more prominent,especially the blasting vibration effects constraints the blasting excavation.According to the actual monitoring of the vibration on the surrounding buildings during the blasting excavation of the entrance and exit segments of the long urban cross-ridge tunnel in Dabanshan,the blasting seismic wave propagation attenuation law was analyzed.It is concluded that there is an inverse correlation between the integrity of the surrounding rock and the values of the key parameters K,α taken in the Sadovsky formula under the same rock type,the better the integrity of rock,the lower the values of the key parameters.The proposed values of K and α are 350 and 1.9 for the entrance section and 250 and 1.85 for the exit section,respectively.The blast vibration velocity propagation curves were plotted for three representative charge volume.Based on the plotted curves and the vibration velocity control requirements of the site building,the starting position of the tunnel blasting excavation from the tunnel entrance was determined.And it provides a reference for the actual tunnel excavation project with poor grade and integrity of surrounding rock and dense surrounding buildings.