Abstract

Drill and blast is a major method for foundation excavation in nuclear power plant engineering. For transporting heavy components to engineering construction, the blast-induced vibration of foundation excavation in a road corridor may has a great influence on new pouring mass concrete and surrounding bedrock in Xianning Nuclear Power Station, which will affect the safety of the engineering construction. So it is necessary to monitor the process of blasting excavation and put forward effective control measures on blasting vibration effect, in which the peak particle velocity (PPV) attenuation law are investigated through regression analysis of practical field data by Duvall empirical formula and the time-frequency characteristics was analyzed by wavelet transform and wavelet package decomposition. By analyzing the velocity amplitude and power spectrum density amplitude of wavelet components, it shows the blast energy of original vibration signal is mainly within the frequency below 250 Hz and has three sub-band which varies from 10 Hz to 30 Hz, from 40 Hz to70 Hz and from 75 Hz to 125 Hz, respectively. Wavelet packet analysis indicates the energy of the signal in 0-125 Hz accounts for 94.25 % of the total signal. At the same time, for the sake of ensuring the safety of road corridor, Chinese admissibility standards (GB6722-2014) of blasting-induced vibration and the constants obtained from the regression were used to establish the maximum explosive charge per delay for an acceptable ground vibration level that would not cause damage for new pouring mass concrete and bedrock in road corridor. The safety criteria of particle vibration velocity for new pouring mass concrete and bedrock in road corridor could be both set as 5 cm/s, which show the remarkable effect on blasting damage control of the new pouring mass concrete and surrounding bedrock, the results demonstrate that controlling maximum explosive charge per delay methodology can be commendably applied to road corridor to control blasting-induced vibration effects.

Highlights

  • China is in the stage of rapid economic development and continuous infrastructure construction, blasting engineering plays an increasingly prominent role in highway excavation, hydropower construction, underground space development and other fields [1, 2]; a series of negative effects caused by blasting have attracted widespread attention

  • According to the design requirements of Xianning nuclear power station, it is necessary to carry out foundation excavation blasting of road corridor for transporting heavy components to engineering construction, the stress wave and high pressure gas in the process of blasting excavation may cause different degrees damage to the new pouring mass concrete and surrounding rock mass, which will affect the safety of engineering construction, so it is necessary to monitor the process of blasting excavation and put forward effective control measures on blasting vibration effect for the safety of near new pouring large volume concrete and surrounding rock mass in blasting field

  • For transporting heavy components to engineering construction, the blast-induced vibration of foundation excavation in a road corridor may has a great influence on new pouring mass concrete and surrounding bedrock in Xianning Nuclear Power Station, which will affect the safety of the engineering construction; the study on peak particle velocity (PPV) attenuation law and time-frequency characteristics of blasting vibration signal is of great importance to control vibrations induced by bench blasting

Read more

Summary

Introduction

China is in the stage of rapid economic development and continuous infrastructure construction, blasting engineering plays an increasingly prominent role in highway excavation, hydropower construction, underground space development and other fields [1, 2]; a series of negative effects caused by blasting have attracted widespread attention. For transporting heavy components to engineering construction, the blast-induced vibration of foundation excavation in a road corridor may has a great influence on new pouring mass concrete and surrounding bedrock in Xianning Nuclear Power Station, which will affect the safety of the engineering construction; the study on peak particle velocity (PPV) attenuation law and time-frequency characteristics of blasting vibration signal is of great importance to control vibrations induced by bench blasting. In order to reduce the damage extent to new pouring mass concrete and surrounding rock mass during the foundation blasting excavation of the road corridor, the peak particle velocity (PPV) attenuation law of blasting vibration signal has been studied through regression analysis of practical test data by Duvall empirical formula and the time-frequency characteristics of blasting vibration signal was analyzed by wavelet transform and wavelet packet transform. Some feasible measures to mitigate the negative effects of blasting induced vibrations is given, Chinese admissibility standards (GB6722-2014) of blasting induced vibration and the constants obtained from the regression were used to establish the maximum explosive charge per delay for an acceptable ground vibration level that would not cause damage for new pouring mass concrete and bedrock in road corridor

Characteristics of wave propagation
Wavelet transform and wavelet packet transform
Safety criterion of blasting vibration effect
Introduction to Xianning Nuclear power station
Time-frequency characteristics for blasting vibration signal
Initiative control for blasting vibration effect
Findings
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call