Polymetallic nodules are distributed in the deep-sea plains at around 5.0 km depth,where the soft sediments have high water content and low bearing capacity.When a deep-sea mining vehicle touches down,the soft sediments under the vehicle can be easily disturbed and lead to vehicle sinking,which will significantly affect the normal operation and may even cause the machine to shut down.The sinking of the mining vehicle is closely related to the stress distribution under the vehicle after touchdown,but there is no theoretical analysis on this.By conducting bottoming test on a mining vehicle model at different bottoming speeds,the study reveals the variation of the vertical stress under the vehicle with time and the stress distribution range.Based on the traditional theory,a theoretical formula considering the effect of the crawler track has been derived and verified.The research found that the stress value under the vehicle will rapidly increase and stabilize,and the time required to reach the stable stress value is inversely proportional to the bottoming speed.As the bottoming speed increases,the shape of the stress bulb under the vehicle changes from a smooth single peak to a single peak with platforms on both sides,and the stress propagation distance directly under the vehicle body is the farthest.Compared to a flat plate,the stress influence depth of the crawler track plate is significantly increased.Error analysis shows that the improved theoretical formula has better agreement with the experimental results than the traditional theory,improving the accuracy of stress calculation after the deep-sea mining vehicle touches down.This study discusses the seabed stress distribution after the mining vehicle touches down,which can provide theoretical reference for the design of low-disturbance and anti-sinking deep-sea mining vehicles.
维普
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