Design Model of the Tunnel Axis and its Algorithm Implementation

2011 ◽  
Vol 103 ◽  
pp. 570-577
Author(s):  
Yue Qiang Li ◽  
Ya Ke Liu

With a large number of construction projects building in urban rail construction, it’s very necessary for researching on the construction axis. Construction axis of the subway is consisted of line segment, circular arc segment and transition curve. The paper introduces design models and algorithms of the tunnel boring machine (TBM) axis (DTA). By analyzing the DTA characteristics of each curve, summing up their general characters, we ultimately make a unified common algorithm and geodetic coordinate calculation model of the design axis in horizontal and vertical planes. It will be very useful for the process of underground construction.

2021 ◽  
Author(s):  
Irene Hartl ◽  
Ingrid Schlögel ◽  
Robert Wenighofer ◽  
Jakob Gallistl

<p>Geological conditions and their uncertainties are a major risk factor in underground construction projects. To ensure a fast, smooth and save completion of the excavation, a prediction of the geological conditions in front of the working face during tunnelling is a topic of great importance.</p><p>Various geophysical methods for a prediction of the conditions ahead of the tunnel face have been developed over the past years, yet, most of them being seismic techniques, which require a short interruption of the excavation to minimise noise interference. However, there is also the approach with TSWD which uses the working TBM (Tunnel Boring Machine) as a source signal and can thus work simultaneously with the excavation. Up to now, this concept has been applied primarily in mechanised tunnelling and there are hardly any applications in conventional tunnelling.</p><p>In the course of several practical experiments at the “Zentrum am Berg” in Eisenerz (Austria), different concepts for a transfer of TSWD from mechanised to conventional tunnelling were developed and tested at scale in an underground research facility. Three machines were used for these tests, an excavator with a hydraulic hammer attached as well as two different drilling jumbos. The devices were equipped with an accelerometer to pick up the source signal at its origin (pilot signal). Different sensor positions were tested using a sledge hammer as a source and evaluated in detail. Moreover, omnidirectional geophones of different sensitivities (4.5 Hz and 27 Hz) were tested and compared as transducers in the adjacent rock mass.</p><p>An essential part of the experiment analysis consisted of the evaluation of the source characteristics as well as the generated spectral bandwidth of the source signal from typical construction machines in conventional tunnelling. Consequently, the outcomes will be another step forward in the development of a TSWD exploration system also applicable to conventional tunnelling projects.</p>


Author(s):  
Ramtin Serajiantehrani ◽  
Saeed Janbaz ◽  
Mohammad Najafi ◽  
Seyed Korky ◽  
Mohammadreza Malek Mohammadi

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

2016 ◽  
Vol 33 (3) ◽  
pp. 317
Author(s):  
Fei Wang ◽  
Mengbo Liu ◽  
Long Chen ◽  
Wen Liu ◽  
Linmeng Tang

Author(s):  
Gi-Jun Lee ◽  
Hee-Hwan Ryu ◽  
Tae-Hyuk Kwon ◽  
Gye-Chun Cho ◽  
Kyoung-Yul Kim ◽  
...  

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Ye Zhu ◽  
Wei Sun ◽  
Junzhou Huo ◽  
Zhichao Meng

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.


Author(s):  
Long-Iong Wu ◽  
Kuan-Lwun Shu

This article presents a method for designing a planar guide device that can guide sliders to move along a straight-curved rail and can eliminate the backlash between the slider and the rail throughout the whole range of the slider travel. The guide device has many sliders and each slider has three rollers that can separately roll on both sides of the rail. The straight-curved rail is composed of straight sections, connection sections, and circular-arc sections. For each slider, the three normal lines through the contact points between the rollers and the rail must always intersect at a common point, which is an instant center. Using this as a basis, the side profiles of the straight-curved rail can be determined. To avoid infinite jerk of the slider motion, the pitch curve of the connection section should consist of a transition curve, which is interposed between the straight line and the circular arc.


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