The authors performed ground motion measurements during blasting operations at several tunnels in association of rehabilitating the intercity roadways in Turkey in Zonguldak. The authors have been monitoring the blasting-induced vibrations in adjacent tunnel near at Üzülmez tunnel excavated through an urbanized area to see the effects of blasting on adjacent tunnels and ground surface. In this study, the outcomes of monitoring of vibrations in tunnels and at ground surface are presented and some empirical attenuation relations used for assessing the effects of blasting on the adjacent structures are proposed. The authors also attempted to infer in-situ stresses using the damage of blasted-holes. The authors utilized the fault striation method (Aydan 2000) and blasted hole damage method (BHMD) (Aydan 2013). Aydan (2013) proposed a method to estimate the stress state from the damage zone around blasted holes. This method was applied to damage zone around blasted holes and some stress inferences made for the tunnel face. Estimations of in-situ stress estimations from different methods were compared. Finally, the outcomes of the field monitoring of blasting-induced vibrations of tunnels and their environmental effects are presented and discussed.
Blasting is the most commonly used excavation technique in mining and civil engineering applications. Blasting induces strong ground motions and fracturing of rock mass in rock excavations. Blasting may also induce some instability problems on rock slopes, tunnels, mines as well as adjacent structures near the mines. In addition, the drilling and blasting operations may induce vibrations and environmental problems in urbanized areas.
Various techniques are used to dimish the effects of blasting on structures on ground surface and the pillar between the adjacent tunnels below the allowable limits. Blasting may also impose undesirable dynamic loads on the support system of the tunnels.
Presently several tunnels in association of rehabilitating the intercity roadways in Turkey have been excavated in Zonguldak and its close vicinity using the drilling and blasting technique. These tunnels are very close to main highways and they may pass through densely populated areas. Furthermore, there are also concerns on the stability and damage to nearby touristic karstic caves due to blasting operation in these newly excavated tunnels.
