Structural planes surveying and fractal dimension characteristics of tunnel face based on digital photogrammetry
- PDF / 2,932,996 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 45 Downloads / 192 Views
TECHNICAL NOTE
Structural planes surveying and fractal dimension characteristics of tunnel face based on digital photogrammetry Shangqu Sun 1 & Shucai Li 1 & Liping Li 1 & Shaoshuai Shi 1 & Hongliang Liu 1 & Jie Hu 1 & Shen Zhou 1 Received: 11 April 2018 / Accepted: 10 October 2018 # Saudi Society for Geosciences 2018
Abstract Based on the digital photogrammetry, technical operation standards, such as the layout of the controlling points and optimization of shooting area, and some technical essentials have been proposed. Thus, the tunnel excavation contour and joint parameters can be obtained rapidly and accurately without interfering with tunneling operations. For practical tunnel engineering, the threedimensional models of 62 tunnel working faces have been established, and then the overbreak and underbreak data and the joint parameters have been collected by Siro 6.0, an artificial-intelligent interaction platform. Based on the statistical self-similarity of tunnel section contour and the method of box dimension, the relationship between the fractal dimensions and the surrounding rockmass classifications, orientation, joint spacing, and included angle between joint strike and tunnel axis has been analyzed. The result shows that the fractal dimension reduces with decrease of the surrounding rockmass classification. When the joint spacing is fixed, the fractal dimension shows exponential decay with the increase of included angle between joint strike and tunnel axis. When the angle is fixed, the fractal dimension decreases with the increase of joint spacing. For the surrounding rockmass of classification III, the relationship between the fractal dimension and joint dip angle is approximately normally distributed and the fractal dimension reaches the maximum value as the joint dip angle ranges from 35° to 55°. In addition, the fractal dimension decreases linearly with the increase of joint spacing, presenting two segments divided by the intersection with joint spacing equal to 32.65 cm. Keywords Sirovision . Close shot photogrammetry . Overbreak and underbreak . Joint parameters . Fractal dimension
Introduction * Liping Li [email protected] Shangqu Sun [email protected] Shucai Li [email protected] Shaoshuai Shi [email protected] Hongliang Liu [email protected] Jie Hu [email protected] Shen Zhou [email protected] 1
Research Center of Geotechnical and Structural Engineering, Shandong University, Jingshi Road, Jinan 250061, China
Despite the intrinsic destructive characteristic, drilling and blasting method is the most satisfactory tool for excavation of rocks (Mohammadi et al. 2015). Excavation of tunnels in rock by blasting inevitably results in a tunnel perimeter that is in some places larger and in others smaller than called for in the tunnel design. This is called, respectively, overbreak and underbreak (Maerz et al. 1996). However, overbreak and underbreak are both undesirable in tunnel excavation, costing money and time to remedy. (Singh and Xavier 2005). In addition, overbreak is usually accompanied b
Data Loading...
