"On utilization of underground space to protect historical relics model", by Zhang Ping, Chen Zhilong, Yang Hongyu, Wang Hui
"Nowadays, under the condition of economic globalization, a lot of valuable historical relics all over the world are in danger because of natural environment and disasters caused by human destruction. The large-scale development and construction of cities and rebuilding of old cities also bring serious “constructive destruction” for all kinds of historical relics. Therefore, it becomes more important to strengthen historical relics protection than ever before. The article expounds the importance of historical relic protection through underground and proposes different models of development of underground space in allusion to relic classification. The use of underground space cannot only alleviate contradiction of urban development and relics protection, but also provide effective measures for protection of valuable relics which are restricted by surface condition, thereby can realize sustainable development of relics protection."
Which seems to be, literally, about building underground complexes to store your treasures in. I've a feeling many of us have an urge right now to reach for the nearest graph paper.
"Tunnel boring machines under squeezing conditions" by M. Ramoni, G. Anagnostou
"Squeezing ground represents a challenging operating environment as it may slow down or obstruct TBM operation. Due to the geometrical constraints of the equipment, relatively small convergences of one or two decimetres may lead to considerable difficulties in the machine area (sticking of the cutter head, jamming of the shield) or in the back-up area (e.g., jamming of the back-up equipment, inadmissible convergences of the bored profile, damage to the tunnel support). Depending on the number and the length of the critical stretches, squeezing conditions may even call into question the feasibility of a TBM drive. This paper sets out firstly to give an overview of the specific problems of TBM tunnelling under squeezing conditions; secondly to analyse the factors governing TBM performance by means of a structured examination of the multiple interfaces and interactions between ground, tunnelling equipment and support; and thirdly to provide a critical review of the technical options existing or proposed for coping with squeezing ground in mechanized tunnelling."
Primarily this is an issue when an umber hulk gets stuck and can't back himself out. Not pretty.
Case studies of groundwater flow into tunnels and an innovative water-gathering system for water drainage, by Diyuan Li, Xibing Li, Charlie C. Li, Bingren Huang, Fengqiang Gong, Wei Zhang
"Groundwater inflow into tunnels can constitute a potential hazard and also is an important factor influencing the speed of tunnel excavation. In this paper the results of numerical modelling are presented to investigate the groundwater flow and the distribution of the pore pressure around tunnels. Two types of tunnels, double-arch tunnel and twin-tube tunnel, were studied. Potential leakage places are identified for the two types of tunnels. The most permeable place in the double-arch tunnel is at the contact interface between the middle wall and the overlying rock. The results of numerical modelling are compared with field observations in the case studies. Based on the results of numerical modelling and the field investigations, an innovative water-gathering system for reducing water leakage was proposed and applied in some tunnels on ChangJi Expressway in China. The water-gathering system can be quickly glued to the rock surface and easily installed for tunnelling. It can be applied in tunnels where water-bearing fractures are well-developed in the rock mass."
I've had numerous issues with groundwater seepage in my underground constructions (except when I've actually used reputable dwarven contractors with a proven track record), so this one holds promise.
Natural ventilation, harnessed by New Kingdom Egyptian tomb builders, may explain the changed floor levels in the Valley of the Kings tomb KV5, by Don Grubble
This article offers a plausible explanation for the floor level changes made during the construction of tomb KV5 in the Valley of the Kings. The construction of ancient Egyptian single entrance subterranean corridor tombs would have required a natural ventilation system; otherwise workers would have suffocated from the diminished oxygen in the depths of the tunnels and from the dust that resulted from the construction. This article postulates that the ancient Egyptians understood the concept of air exchange where, when in the desert, the outside air temperature drops dramatically in the evening causing a cool air draught to flow into the excavations that flushed out the stale air and dust, and replaced it with fresh air, enabling the workers to continue working day after day.
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