발파공간 지연시차가 지반진동에 미치는 영향

Abstract

In the past, rock blasting work for excavation work on the ground was limited. In recent years, a large building from the mountains wallpaper Dig site and construction of apartments for redevelopment for housing and crowded around the existing structures within the city center is underway. Furthermore, the underground reserve base, development of underground space has been expanded to in deep underground is increasing the demand. This specialization of blasting construction, enlargement, depending on the national scene with a large blast on the rise, and the use of explosives is increasing each year. Today, our society through the process of industrialization continued growth comes during a highly neglected environmental problems, especially in the field of construction noise and vibration issues are rapidly emerging in recent years. This quantitative growth to qualitative growth in the pursuit of change is the situation. In addition, the government, like in reality, considering the environmental impact of the regulatory environment, as a means of dispute conciliation committee established by the permanent organization is operating the sleep. So blasting operations are subject to the more stringent regulations. Blasting engineers compared to conventional blasting methods are looking for effective vibration control methods. And when the blasting was designed they considered a top priority to safety in efficiency, reliability and safety of design variables. Determinings the propagation characteristics of blasting vibration factor are location and blasting conditions. Location means that the blasting site and the geometric shape of the structure, the target of rocks and geological features include the mechanical properties. Blasting conditions means that the type of using explosives, weight per delay, composition charging, blasting method, tamping condition, number of free face, distance. Test blasts(2～3holes) were carried out a total of 16 times using different spacing, burden, drilling length, charge per delay and was derived the formula to predict blast vibration. This study investigated the characteristics of vibration by analysis of the nomogram and prediction of ground vibration about component(Transverse, Vertical, Longitudinal) particle velocity, peak particle velocity(PPV), peak vector sum(PVS) from delay time(20, 25ms) by the formula to predict ground vibration. This study investigated the characteristics of vibration by analysis of the nomogram and prediction of ground vibration about component(Transverse, vertical, longitudinal) particle velocity, peak particle velocity(PPV), peak vector sum(PVS) from delay time by the formula to predict ground vibration. And it analyzed the trends of vibration damping by standards charge 0.5, 1.6, 5, 15kg. Standards charge is "Blasting design and construction guidelines to road construction" by the Ministry of Land, Transport and Maritime Affairs. Depending on the charge in favor of vibration control method is proposed. Thus, when the design was to be used as a variable.

The result of this study can be summerized as follows (1) Vibration velocity were predicted from an average ground vibration prediction equation of component(T, V, L) velocity depending on the delay time(20, 25ms) at 5～200m distance. As a result, the vibration level of transverse component of the vibration level is lower than the vertical and longitudinal component of the vibration levels in the near distance and the vibration level of transverse component of the vibration level is higher than the vertical and longitudinal component of the vibration levels in the long distance. The vibration level of longitudinal component of the vibration level is lower than the vertical component of the vibration levels and the vibration level of longitudinal component of the vibration level is higher than the transverse component of the vibration levels in the near distance. (2) Vibration velocity were predicted from an average ground vibration prediction equation of peak particle velocity(PPV) and peak vector sum(PVS) depending on the delay time and priming location at 5～200m distance. The case of 1(20ms) and 2(25ms) reversal of the two components were tend to be different, but vibration level of Case 2(25ms) in the near distance were predicted lower and vibration level of Case 2(20ms) in the long distance was predicted lower.