Drilling And Blasting Construction Control Research Of The Neighborhood Rock Tunnel In Complex Condition

In China, Qingdao Jiaozhou Bay tunnel project is the second undersea tunnel, also is the longest tunnel, which is a important channel for connected with the main city and auxiliary city of Qingdao, the tunnel's construction can fundamentally solve the "hunger gap", it is the strong support and major engineering measures for Qingdao to be a modern international city.This paper takes Qingdao Jiaozhou Bay left line rock tunnel with small spacing as the background, mainly research the construction crucial technique of the rock tunnel with small spacing. Shallow, small spacing (minimum distance is 0.25m), through the building are the main features of the small space rock tunnel, how to maintain rock layer and rock pillar stability between two tunnels in the process of tunnel construction and to control blasting seismic wave's effect on the buildings located above the tunnel are the focus of this paper. The main contents are as follows:1. In order to better control the rock tunnel blasting construction effects on tunnel rock and the buildings above the tunnel, study for the related theory of rock blasting broken mechanism, rock broken form, blasting stress wave.2. To study the blasting programs and building ground surface particle blasting vibration monitoring programs, and to analyze the vibration velocity of 36 groups monitoring ground surface particle. Statistical principle is applied for the best ground surface particle vibration velocity regression formula. According to the regression formula, calculated the blasting charge maximum amount of single-stage to guide the design and construction of tunnel blasting, to ensure the safety of the above the tunnel.3. Using numerical calculation to research the small distance tunnel's different excavation program, and further to optimize the support parameters; Proposed that increase right hole radial support capability and left hole slice shear capacity, to ensure the stability of the tunnels' middle rock pillar; Based on the numerical simulation, thinking the actual engineering situation, reached the optimal solution to construction, ensured the safety and rapid construction of tunnels with small spacing.4. On the rock pressure, initial grille steel frame internal forces, stress between the second and initial supporting, and second supporting concrete strain carried on the key monitoring and measurement, and had a comprehensive analysis of the monitoring data, mastered the surrounding rock, the early support, second lining's stress state, to verify the reasonableness of the construction program, so as to provide a experience to the construction of similar tunnel.