Management of rock bursts during excavation of the deep tunnels in Jinping II Hydropower Station

Shan, Zhigang; Peng, Yan

doi:10.1007/s10064-010-0266-2

Cited by 72 publications

(27 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For an evaluation of rockburst intensity, four grades were proposed in the tunnels at the Jinping II Hydropower Station by Shan and Yan (2010), as follows: light class (Grade I), middle class (Grade II), intense class (Grade III), and extremely intense class (Grade IV). Figure 5 shows the extremely intense rockburst on the north sidewall of the auxiliary tunnel #B at a depth of 2,300 m. Due to the severe impact, grid arch frames, steel fiber shotcrete, and fractured rock mass were ejected to the opposite sidewall, the surface support system was damaged, and almost all of the rock bolts were pulled out.…”

Section: Characteristics Of Rockbursts In the Auxiliary Tunnelsmentioning

confidence: 99%

“…The deep tunnel sections of the Jinping II Hydropower Station are prone to extremely intense rockbursts (Shan and Yan 2010;Wu et al 2010). Of these tunnels, two headrace tunnels and a drainage tunnel are excavated by TBMs.…”

Section: Introductionmentioning

confidence: 98%

“…Based on their statistical analysis of the relationship between rockburst position and tunnel face distance, Shan and Yan (2010) showed that the majority of rockbursts in tunnel projects occurred in a range of 2 diameters behind the tunnel face, while the initial supporting area of the TBM (L1 area) was located just within this range behind the shield. Because of the peak activity of rockbursts, the support construction is very difficult and dangerous in the L1 area.…”

Section: Introductionmentioning

confidence: 99%

“…The The relationship between the number of rockbursts and the time since the first rockburst after excavation(Shan and Yan 2010) The relationship between the number of rockbursts and their distance from the working face(Shan and Yan …”

mentioning

confidence: 99%

See 3 more Smart Citations

A Top Pilot Tunnel Preconditioning Method for the Prevention of Extremely Intense Rockbursts in Deep Tunnels Excavated by TBMs

et al. 2011

View full text Add to dashboard Cite

The headrace tunnels at the Jinping II Hydropower Station cross the Jinping Mountain with a maximum overburden depth of 2,525 m, where 80% of the strata along the tunnels consist of marble. A number of extremely intense rockbursts occurred during the excavation of the auxiliary tunnels and the drainage tunnel. In particular, a tunnel boring machine (TBM) was destroyed by an extremely intense rockburst in a 7.2-m-diameter drainage tunnel. Two of the four subsequent 12.4-m-diameter headrace tunnels will be excavated with larger size TBMs, where a high risk of extremely intense rockbursts exists. Herein, a top pilot tunnel preconditioning method is proposed to minimize this risk, in which a drilling and blasting method is first recommended for the top pilot tunnel excavation and support, and then the TBM excavation of the main tunnel is conducted. In order to evaluate the mechanical effectiveness of this method, numerical simulation analyses using the failure approaching index, energy release rate, and excess shear stress indices are carried out. Its construction feasibility is discussed as well. Moreover, a microseismic monitoring technique is used in the experimental tunnel section for the real-time monitoring of the microseismic activities of the rock mass in TBM excavation and for assessing the effect of the top pilot tunnel excavation in reducing the risk of rockbursts. This method is applied to two tunnel sections prone to extremely intense rockbursts and leads to a reduction in the risk of rockbursts in TBM excavation.

show abstract

Section: Characteristics Of Rockbursts In the Auxiliary Tunnelsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

A Top Pilot Tunnel Preconditioning Method for the Prevention of Extremely Intense Rockbursts in Deep Tunnels Excavated by TBMs

et al. 2011

View full text Add to dashboard Cite

show abstract

“…The auxiliary tunnels were connected before the drainage and headrace tunnels were constructed. Rockburst intensity in the auxiliary tunnels was classified into four grades: light class (grade I), moderate class (grade II), intense class (grade III), and extremely intense class (grade IV) (Shan and Yan 2010).…”

Section: Introductionmentioning

confidence: 99%

Case Histories of Four Extremely Intense Rockbursts in Deep Tunnels

et al. 2012

View full text Add to dashboard Cite

In the process of excavating seven parallel tunnels at the Jinping II Hydropower Station, several extremely intense rockbursts occurred, killing and injuring construction workers and damaging several sets of equipment. Based on the characteristics and mechanisms of these rockbursts, four typical events were selected and their temporal and spatial characteristics were here described in detail. The geological conditions revealed after the rockbursts were surveyed carefully. The responses of support elements were also analyzed. The details documented in each case provide not only an important reference for understanding the development mechanisms of rockbursts but also a basis for the selection and development of rockburst prevention measures in deep hard rock tunnels.

show abstract

Simulating the response of buried structures to external blast loads: Methods, challenges, and advances

Mohammadi

Khalilpour

Sareh

2022

Engineering Reports

View full text Add to dashboard Cite

Various methods have been proposed to ensure the serviceability of buried structures such as road tunnels, urban utility tunnels, water conduits, underground shelters, and deposition chambers against extreme loads, the most common of which are experimental and computational methods. An external explosion in the vicinity of such structures is one of these extreme loads. In general, different types of external blasting for buried structures can be classified as surface blasting, coupled or uncoupled buried explosions, excavation by drilling and blasting near the structure, and the accidental detonation of explosive depositions. Laboratory or field tests for explosions are usually limited by financial and safety constraints; therefore, numerical simulations are often regarded as a vital tool in the study of such problems. Though computer software and hardware have improved rapidly in recent decades, and various numerical solvers have been developed, there is no universal method for solving all external explosion problems. Each numerical method can produce sensible results under certain conditions and assumptions, along with its limitations in computational cost. Consequently, these problems have been particularly difficult to investigate, and even in some cases, the results of different studies seem to be inconsistent. Besides providing an extensive review of the available literature in the field of numerical simulation of external explosions near buried structures and a discussion of the damage criteria associated with such explosions, this study also highlights some inconsistencies that may need further investigation.

show abstract

Management of rock bursts during excavation of the deep tunnels in Jinping II Hydropower Station

Cited by 72 publications

References 1 publication

A Top Pilot Tunnel Preconditioning Method for the Prevention of Extremely Intense Rockbursts in Deep Tunnels Excavated by TBMs

A Top Pilot Tunnel Preconditioning Method for the Prevention of Extremely Intense Rockbursts in Deep Tunnels Excavated by TBMs

Case Histories of Four Extremely Intense Rockbursts in Deep Tunnels

Simulating the response of buried structures to external blast loads: Methods, challenges, and advances

Contact Info

Product

Resources

About