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Groundwater Control for Tunnelling Projects
Published in Pat M. Cashman, Martin Preene, Groundwater Lowering in Construction, 2020
A wide range of shaft sinking methods are commonly used, as detailed by Allenby and Kilburn (2015), Faustin et al. (2017) and Smith (2018), with the choice of method depending on a variety of factors, including shaft depth and diameter, ground conditions and environmental constraints such as the settlement sensitivity of nearby existing structures.
The role of mechanized shaft sinking in international tunnelling projects
Published in Daniele Peila, Giulia Viggiani, Tarcisio Celestino, Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art, 2019
All installations, including the lining erection, are remotely controlled from the surface. No personnel have to enter the shaft until it has reached the final depth and is fully secured. In general, mechanized shaft sinking requires less personnel and machinery on site, which leads to minimized risk exposure.
The role of mechanized shaft sinking in international tunnelling projects
Published in Daniele Peila, Giulia Viggiani, Tarcisio Celestino, Tunnels and Underground Cities: Engineering and Innovation Meet Archaeology, Architecture and Art, 2020
All installations, including the lining erection, are remotely controlled from the surface. No personnel have to enter the shaft until it has reached the final depth and is fully secured. In general, mechanized shaft sinking requires less personnel and machinery on site, which leads to minimized risk exposure.
Editorial
Published in Applied Earth Science, 2018
Fast forward to today and we are looking at a real example of a multi-million-ounce goldfield in Australia that is mining high-grade ore by decline methods at 700 m depth. If anything, the ore is improving with depth. What is the appropriate development method to mine deeper than the present 700 m depth? Financial and engineering models that use the projected price of steel, digging, labour and electrical work to name a few items coupled with an informed discount rate and gold price estimate, should play a role here. Also, the availability of shaft sinking expertise must be considered. However, the decision of shaft or decline is not to be left solely to engineers and financial planners as nobody wants a shaft that has no ore to haul, and neither do future generations want to see a mining operation cease at 2 km depth and their jobs disappear because it has become too slow and expensive to drive vehicles up and down its decline.
Evolution mechanism of temperature field of the frozen wall of the vertical shaft under cold energy extraction
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Hanwen Zhang, Weipei Xue, Zhishu Yao, Zongjin Wang, Feng Wang, Cheng Wu
Artificial ground freezing was first put forward by Friedrich Poetsch in the 19th century and was originally used in mining engineering (Cheng 2016). Artificial ground freezing is to use artificial refrigeration technology to freeze the ground water into ice to form frozen wall (Lu, Chen, and Chen 2021). The frozen wall will increase the stability and strength of the soil and form temporary support, which is convenient for underground engineering construction (Yang and Rong 2020). After the construction of the artificial ground freezing, the average temperature of the frozen wall is very low, in which a large amount of cold energy is stored. Frozen wall is bulky, just finished construction of frozen wall is equivalent to a huge cold storage tank (Ji 2017). If the cold energy of the frozen wall is not extracted and applied, it will gradually dissipate under the action of geothermal, resulting in a serious waste of resources. Taking Wanfu Coal Mine as an example, the frozen wall at the end of shaft construction is used as an underground cold source to extract cold energy and apply it to the refrigeration system to save nearly 1.36 × 106 kWh of electric energy (Fan, Zhang, and Zhou 2016). At the same time, artificial ground freezing is not only used in shaft sinking construction but also widely used in subways, tunnels, foundation pits, and other engineering fields (Rong et al. 2022). If the excess cold energy of the frozen wall in all freezing projects is reasonably extracted and applied, it will save a lot of energy and alleviate the problem of national energy shortage. Therefore, it is urgent to study the extraction technology from excess cold energy of frozen walls.
Directional fracturing excavation technology based on liquid CO2 phase transition in freezing shaft sinking
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Shuliang Chen, Bingxiang Huang, Xinglong Zhao, Weiyong Lu, Zechu Tian
Freezing shaft sinking is a common construction method for the coal mine vertical shaft construction in deep alluvial or water-rich soft rock strata (Song, Yang, and Li 2010; Zhang, Han, and Yang 2017; Zhang, Yang, and Wang 2018). In the field, the strata were artificially frozen into frozen soil (Feng 2015; Li 2017; Mauro, Normino, and Cavuoto 2020; Qi, Zhang, and Yang 2020; Zhang 2012). Those frozen soil sections were characterized by long freezing duration and relatively good hardness, which makes excavation relatively more difficult (Lei and Ma 2005; Yang, Ma, and Wang 1997). Research on the excavation technology of freezing shaft sinking had important engineering significance to improve efficiency.