Blasting and the transmission of vibration involve numerous variables which makes it impossible to predict the levels of vibrations. Therefore an effective blast design and optimization require a multitude of variables be integrated into a single instance. In prior research the existence of the strong relation between PPV and damage to structures has been well established. Besides PPV, the frequency is one of the most important factors controlling the response of structures. This paper presents a case history of Olympic Stadium renovation in Helsinki, Finland with a focus on blasting near the Olympic Stadium Tower. It will be concluded whether the current vibration criteria, measurement and approach are suitable and sufficient for near-structure blasting.
Blasting and explosions in the vicinity of retaining structures raise two principal areas of concern. First, an air blast spreads outward over the ground surface from the point of near surface explosion. These shocks waves induce stress waves in the ground producing dynamic stresses on the structures. In addition to that, the stress waves originating from the point of an underground explosion and moving directly through the ground. These waves induce stresses in any wall or underground structure along their path [1].
There are many variables and "site factors" that collectively result in the formation of a complex vibration waveform. Many parameters of both controlled and uncontrolled nature influence the amplitude of ground vibration(safety, distance from the source, rock properties, local geology, surface topography, explosive quantity and properties, geometrical blast design, operational parameters, such as initiation point and sequence, delay intervals patterns, firing method, etc.) [2, 4].
In order to control and protect the excited structures from deleterious effect of ground and air vibration, standards and regulations have been established. These regulations vary from country to country depending on the type and construction material used. In addition, many damage criteria and propagation equations have been designed that derive varying degree of success [4, 6].
