Interface prediction ahead of the excavation front by the tunnel-seismic-while-drilling (TSWD) method

Geophysics ◽  
2007 ◽  
Vol 72 (4) ◽  
pp. G39-G44 ◽  
Author(s):  
Lorenzo Petronio ◽  
Flavio Poletto ◽  
Andrea Schleifer
Keyword(s):  
Seismic Data ◽  
Reference Signal ◽  
Tunnel Boring Machine ◽  
S Wave ◽  
Tunnel Boring ◽  
Vertical Seismic Profiling ◽  
Mechanical Excavation ◽  
Seismic Sensors ◽  
Interface Prediction ◽  
Interval Velocities

Predicting geologic interfaces ahead of a tunnel front is of major importance when boring tunnels. Unexpected variations in ground properties can cause problems for tunnel-boring advance and risk for human safety. The tunnel-seismic-while-drilling (TSWD) method utilizes noise produced during mechanical excavation to obtain interpretable seismic data. This passive method uses accelerometers mounted on the advancing tunnel-boring machine (reference signals) together with seismic sensors located along and outside the tunnel. Data recorded by fixed sensors are crosscorrelated with the reference signal and sorted by offset. Similar to reverse vertical seismic profiling, crosscorrelated TSWD data are processed to extract the reflected wavefield. During mechanical excavation of a [Formula: see text] tunnel through upper Triassic dolomite, a survey was performed to predict geologic interfaces. Faults intersecting the tunnel were observed on seismic TSWD data and later were confirmed by geostructural inspection. P- and S-wave interval velocities obtained by TSWD data along the bored tunnel were used to compute dynamic rock moduli to support tunnel completion.

Full‐waveform processing and interpretation of kilohertz cross‐well seismic data

Geophysics ◽  
1993 ◽  
Vol 58 (9) ◽  
pp. 1248-1256 ◽  
Author(s):  
Ashraf A. Khalil ◽  
Robert R. Stewart ◽  
David C. Henley
Keyword(s):  
Oil Recovery ◽  
Seismic Data ◽  
Shear Waves ◽  
Synthetic Seismograms ◽  
Oil Field ◽  
S Wave ◽  
Sonic Log ◽  
The Cross ◽  
Interval Velocities ◽  
The Individual

High‐frequency, cross‐well seismic data, from the Midale oil field of southeastern Saskatchewan, are analyzed for direct and reflected energy. The goal of the analysis is to produce interpretable sections to assist in enhanced oil recovery activities ([Formula: see text] injection) in this field. Direct arrivals are used for velocity information while reflected arrivals are processed into a reflection image. Raw field data show a complex assortment of wave types that includes direct compressional and shear waves and reflected shear waves. A traveltime inversion technique (layer stripping via ray tracing) is used to obtain P‐ and S‐wave interval velocities from the respective direct arrivals. The velocities from the cross‐well inversion and the sonic log are in reasonable agreement. The subsurface coverage of the cross‐well geometry is investigated; it covers zones extending from the source well to the receiver well and includes regions above and below the source/receiver depths. Upgoing and downgoing primary reflections are processed, in a manner similar to the vertical seismic profiling/common‐depth‐point (VSP/CDP) map, to construct the cross‐well images. A final section is produced by summing the individual reflection images from each receiver‐gather map. This section provides an image with evidence of strata thicknesses down to about 1 m. Synthetic seismograms are used to interpret the final sections. Correlations can be drawn between some of the events on the synthetic seismograms and the cross‐well image.

Seismic‐while‐drilling by using tunnel boring machine noise

Geophysics ◽  
2002 ◽  
Vol 67 (6) ◽  
pp. 1798-1809 ◽  
Author(s):  
Lorenzo Petronio ◽  
Flavio Poletto
Keyword(s):  
Large Diameter ◽  
Tunnel Boring Machine ◽  
High Amplitude ◽  
Direct Access ◽  
S Wave ◽  
Tunnel Excavation ◽  
Tunnel Boring ◽  
Cutting Head ◽  
Geothermal Wells ◽  
Radial Dimension

The tunnel boring machine (TBM) is used extensively to mechanically excavate tunnels. To optimize the mechanical drilling and work safely, an estimate of the geology to be drilled is necessary. We consider using the elastic waves produced by the TBM cutting wheel to obtain seismic‐while‐drilling (SWD) information for predicting the geology ahead of the drilling front. This method uses accelerometers mounted on the TBM together with geophones located along and outside the tunnel, similar to the technique successfully used to drill oil and geothermal wells. Study of noise and the resolution of the signal produced by the large‐diameter cutting head shows that nonstationary noise separation can be achieved by locating sensors at the front and rear ends of the tunnel. The (higher) resolution in front of the TBM is limited by pilot delays, while the (lower) lateral resolution is limited by the radial dimension of the TBM. Analysis of seismic data acquired in a field test shows that P‐ and S‐wave arrivals have a wide frequency band and high amplitude in seismic traces measured 700 m away from the drilling front. In comparison with SWD applications in wells, tunnel SWD technology has the advantage of allowing direct access to the tunnel front, which makes it easy to connect the TBM reference sensors for while‐drilling monitoring. This method can be successfully applied without interfering with drilling activity to monitor tunnel excavation continuously, reduce risks, and optimize drilling.

Anisotropy effects in P-wave and SH-wave stacking velocities contain information on lithology

Geophysics ◽  
1986 ◽  
Vol 51 (3) ◽  
pp. 661-672 ◽  
Author(s):  
D. F. Winterstein
Keyword(s):  
Seismic Data ◽  
P Wave ◽  
Sh Wave ◽  
S Wave ◽  
Velocity Anisotropy ◽  
Midland Basin ◽  
Wave Data ◽  
Event Times ◽  
Interval Velocities ◽  
Constituent Layer

Depths calculated from S-wave stacking velocities and event times almost always exceed actual depths, sometimes by as much as 25 percent. In contrast, depths from corresponding P-wave information are often within 10 percent of actual depths. Discrepancies in depths calculated from P- and S-wave data are attributed to velocity anisotropy, a property of sedimentary rocks that noticeably affects S-wave moveout curves but leaves the P-wave relatively unaffected. Two careful studies show that discrepancies in depths, and hence in constituent layer thicknesses, correlate with lithology. Discrepancies ranged from an average of 13 percent (Midland basin) to greater than 40 percent (Paloma field) in shales, but were within expected errors in massive sandstones or carbonates. Hence anisotropy effects are indicators of lithology. Analysis of seismic data involved determining interval velocities from stacking velocities, calculating layer thicknesses, and then comparing layer thicknesses from S-wave data with thicknesses from P-wave data. When the S-wave thicknesses were significantly greater than the P-wave (i.e., outside the range of expected errors), I concluded the layer was anisotropic. I illustrate the technique with data from the Paloma field project of the Conoco Shear Wave Group Shoot.

Application of mode‐converted shear waves to rock‐property estimation from vertical seismic profiling data

Geophysics ◽  
1989 ◽  
Vol 54 (4) ◽  
pp. 478-485 ◽  
Author(s):  
Hassan Ahmed
Keyword(s):  
P Wave ◽  
S Wave ◽  
Elastic Parameters ◽  
S Waves ◽  
Seismic Profiling ◽  
Vertical Seismic Profiling ◽  
Property Estimation ◽  
Abrupt Changes ◽  
Highly Correlated ◽  
Interval Velocities

Three‐component vertical seismic profiling (3-CVSP) data were acquired and processed to yield separate estimates of the compressional (P)-wave and shear (S)-wave fields. Interval velocities, [Formula: see text] and [Formula: see text] (of the P and S waves), are computed from the identified onset times at many seismometer positions along the borehole. The ratio [Formula: see text] is calculated and used to compute the Poisson’s ratio and the ratio of incompressibility to rigidity. In a North Sea well, the variation in these elastic parameters was highly correlated with the variation in stratigraphy. Of particular interest was the ability to indicate pore fluids such as gas or water within a reservoir. Abrupt changes of the calculated parameters can be an indicator of the gas‐water to water transition zone.

Transient Property Improvement of Hydraulic Cylinder Control for Tunnel Boring Machine Using Opposite Reference Filter

2020 ◽  
Vol 140 (3) ◽  
pp. 320-325
Author(s):  
Yoshihiro Ohnishi ◽  
Takahisa Shigematsu ◽  
Takuma Kawai ◽  
Shinichi Kawamura ◽  
Noboru Oda
Keyword(s):  
Tunnel Boring Machine ◽  
Hydraulic Cylinder ◽  
Tunnel Boring

Integral hoisting technology of tunnel boring machine in limited space

2016 ◽  
Vol 33 (3) ◽  
pp. 317
Author(s):  
Fei Wang ◽  
Mengbo Liu ◽  
Long Chen ◽  
Wen Liu ◽  
Linmeng Tang
Keyword(s):  
Tunnel Boring Machine ◽  
Tunnel Boring ◽  
Limited Space

A Newly Developed State-of-the-Art Full-Scale Excavation Testing Apparatus for Tunnel Boring Machine (TBM)

2021 ◽  
Author(s):  
Gi-Jun Lee ◽  
Hee-Hwan Ryu ◽  
Tae-Hyuk Kwon ◽  
Gye-Chun Cho ◽  
Kyoung-Yul Kim ◽  
...  
Keyword(s):  
State Of The Art ◽  
Tunnel Boring Machine ◽  
Full Scale ◽  
Testing Apparatus ◽  
Tunnel Boring

scholarly journals A New System to Evaluate Comprehensive Performance of Hard-Rock Tunnel Boring Machine Cutterheads

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Ye Zhu ◽  
Wei Sun ◽  
Junzhou Huo ◽  
Zhichao Meng
Keyword(s):  
Stability Index ◽  
Tunnel Boring Machine ◽  
Efficiency Index ◽  
Structure Design ◽  
Cutting Efficiency ◽  
Evaluation Indexes ◽  
Average Value ◽  
Tunnel Boring ◽  
Rock Tunnel ◽  
Thrust And Torque

AbstractThe accurate performance evaluation of a cutterhead is essential to improving cutterhead structure design and predicting project cost. Through extensive research, this paper evaluates the performance of a tunnel boring machine (TBM) cutterhead for cutting ability and slagging ability. This paper propose cutting efficiency, stability, and continuity of slagging as the evaluation indexes of comprehensive cutterhead performance. On the basis of research of true TBM engineering applications, this paper proposes a calculation method for each index. A slagging efficiency index with a ratio of the maximum difference between the slagging amount and average slagging is established. And a slagging stability index with a ratio of the maximum slagging fluctuation and average slagging is presented. Meanwhile, a cutting efficiency index by the weighed average value of multistage rock fragmentation of a cutter’s specific energy is established. The Robbins and China Railway Construction Corporation (CRCC) cutterheads are evaluated. The results show that under the same thrust and torque, the slagging stability of the CRCC scheme is worse, but the slagging continuity of the CRCC scheme is better. The cutting ability index shows that the CRCC cutterhead is more efficient.

Sign in / Sign up

Export Citation Format

Share Document