Study On Dynamic Response Law And Safety Controlling Technology Of The Surrounding Structures Under The Condition Of Blasting Excavation Of Urban Tunnel In Dense Residential Area

In the21st century, along with the further development of urban transport services, underground tunnel project (light rail, subway, etc.) increase day by day. Tunnel through a large area of dense buildings construction in civil engineering begin to emerge. And the influence of dynamic load on the existing structures is large. Therefore, to carry out the study on tunnel blasting impact on surface buildings is very necessary.This thesis based on Guanhui intercity GZH-7standard systematically research the influence of tunnel blasting on the ground in dense residential areas with the use of four methods (Site monitoring,theoretical analysis,numerical simulation and test section).The main research results are as follows:(1) By the use of three methods (investigation, field vibration monitoring and housing disease analysis), this paper get the power control standards:1.5cm/s which is based on the types and characteristics of buildings in Guanhui intercity GZH-7standard.(2) The principle of surface measuring point arrangement is put forward with the use of three methods (surface velocity monitoring, numerical simulation, test section analysis). And According to the system research of reaction (velocity,stress,displacement) of the different houses Including different types of structure (frame/masonry), different height (2/4layers), different distance (the distance of the center line of tunnel excavation) during Tunnel blasting,the basic principle of building monitoring is also put forward.(3) By the use of numerical simulation in different processes and footage of CD method, and combined with field monitoring data analysis showed that: the half-section excavation on the CD method has a greater Influence (velocity) to surface and should be focused on, especially, the1st part blasting.At the same time, combined with surface building layout, this paper get the suitable construction process for CD method.(4) Through numerical simulation, theoretical analysis and field test, this paper put forward the method of determining the maximum dose which is based on monitoring data and numerical simulation,and give the advice that the maximum dose which is obtained by the Rodolfo J Ki regression analysis method should be multiplied by the coefficient0.9.(5) Based on the millisecond time interval calculation process,this paper use numerical simulation method to comprehensive analyze the differential effect (speed, frequency, etc.) of different time intervals, and propose reasonable millisecond time control of the project.(6) Based on the analysis of Hydraulic blasting used in the project, this paper find that Hydraulic blasting has good shock absorption and dust removing effect.Therefore, hydraulic blasting is very suitable for application in urban tunnel excavation.