Abstract:
The safety control standard of buildings subjected to blast vibrations should not ignore the influence of
the cyclic blasts. It is suggested that the critical peak vibration velocity which makes each part in elastic deformation
stage is taken as the safety control standard and damage law of brick-concrete buildings or structures under frequent
blast vibrations based on the cumulative damage theory and numerical simulations. According to the specific material
parameters and model conditions,the critical peak vibration velocity of an intact brick-concrete structure is 0. 67 cm/s,
and tensile damage occurs in the stress concentration parts. It is therefore recommended that for buildings with weak
anti-vibration ability,such as brick-concrete structures,the range of the safety control standard under frequent blast
vibrations can be determined by multiplying the lower limit value set by the most unfavorable frequency in the current
blasting safety regulations for general civil buildings by a reduction factor,which can be 0. 45 ~ 0. 55. When determining the safety control standard of damaged structures under frequent blast vibrations,the actual damage situation of
the buildings should be comprehensively considered. The vibration safety control standard is taken as the smaller value between the critical peak vibration velocity which does not lead to crack propagation and the critical peak vibration velocity which ensures that all parts of the structure are in elastic deformation stage.
Key words:
blasting vibration; brick-concrete structure; safety control standards; cumulative damage; numerical simulation