Environment
Daniyal Ghadyani; Amirhossein Badraddini; Mohammad Mirzehi Kalateh Kazemi; vahab sarfarazi; Hadi Haeri; Jinwei Fu; Sohrab Naser Mostofi; Vahid Khodabandeloo; Mohammad Fatehi Marji
Abstract
Regarding the hazard-prone working conditions in underground mines, synchronous monitoring and alarm system is vital to increase the safety. By analyzing the accidents in underground mines in Iran, it can be deduced that most fatalities are related to gas leakage, objects drop off on the head, and not ...
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Regarding the hazard-prone working conditions in underground mines, synchronous monitoring and alarm system is vital to increase the safety. By analyzing the accidents in underground mines in Iran, it can be deduced that most fatalities are related to gas leakage, objects drop off on the head, and not using helmets by the staff. Therefore, a smart helmet with the capability of measuring harmful gasses (regarding the type of the mine), detection of the existence of the helmet on the head, temperature and humidity measurement, and detection of blow on the head is designed and fabricated to eliminate the present dangers and problems. This system displays the evaluated data on a developed software through wireless data transmission hardware. The data transmission hardware is the primary a link between the intelligent safety helmet and the software. To follow the idea, practical experiments have been performed in Parvadeh four and East Parvadeh of Tabas coal mine to confirm the validity of data transmission that culminated in successful results. The results were altered by the complexity of the design of the underground spaces so that in a straight direction, data transmission was held until 430 meters. However, further progress was not possible due to tunnel limitations. Data transmission was reduced to 190 meters in access horizons with curvatures or tilts. According to present standards, some thresholds are defined for each of the mentioned cases such that alarm protocol is activated by exceeding these thresholds in critical circumstances. Then the helmet user and the software’s operator will be informed of the occurred danger and will settle the problem. The system outlined in this study ensures performance reliability through its alarm package. A key innovation is the in-depth examination of the impact of head injuries, transforming it into other factors by analyzing relevant content and setting boundaries for assessment rather than using specific numbers. Furthermore, the most evident aspect of this design is the enhancement of the managerial approach, which includes an attendance evaluation platform and performance reporting within the system.
Jinwei Fu; Mohammad Reza Safaei; Hadi Haeri; Vahab Sarfarazi; Mohammad Fatehi Marji; Leige Xu; Ali Arefnia
Abstract
In this work, the mechanical behavior of strata deformation due to drilling and surface loading is investigated using a 3D physical model. For this purpose, a scaled-down physical model is first designed. Then the tunnel drilling and support system are built. The subsidence experiments performed due ...
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In this work, the mechanical behavior of strata deformation due to drilling and surface loading is investigated using a 3D physical model. For this purpose, a scaled-down physical model is first designed. Then the tunnel drilling and support system are built. The subsidence experiments performed due to tunnel excavation and loading in a very dense and loose soil are performed. Soil is clayey sand (SC), and the percentages of its components are as sand (S = 1. 41%), gravel (G = 25%), and clay (C = 9.33%). Unstable tunnel support experiments are also carried out using physical simulation. Finally, deformations of soil surface and subsidence of strata are observed and recorded. In the tunnel with segmental support, 18.75% more load is applied than in the unsupported tunnel, and the total subsidence of the strata is reduced by 36.2%. The area of the deformed inner layers is decreased by 74.2%, and the length of the affected area in the largest layer is decreased by 48%. The depth of the cavity created at the surface is 46.66% less.