Device for modifying a layer of granular medium

Abstract

A device configured to be disposed within a granular medium to raise a layer thereof, the device having: a flexible envelope forming an internal volume; an inflatable element in the internal volume, interposed between the envelope's upper and lower surfaces, the element's inflation and deflation varying the internal volume; an injection device for filling the inflatable element with a fluid; the device being switchable from a first configuration having the inflated inflatable element occupy a first volume to a second configuration having the inflated inflatable element occupy a second volume greater than the first to deform the upper surface vertically to raise the granular medium's layer, and vice versa; the device further being switchable from the first or second configuration to a third configuration having the envelope's lower surface deform vertically to allow the device to ascend through the granular medium. Also, a method of deforming a granular medium layer.

1 - 15 . (canceled) 
     
     
         16 . A device configured to be disposed within a granular medium, such as sand or sediment, to raise a layer of said granular medium, the device comprising:
 a flexible envelope forming an internal volume;   at least one inflatable element housed in the internal volume so as to be interposed between an upper surface and a lower surface of the envelope, the inflation and deflation of said element allowing the internal volume to be varied;   an injection device configured to fill the inflatable element with a fluid;   the device being configured to switch from a first configuration in which the inflatable element is inflated to occupy a first volume to a second configuration in which the inflatable element is inflated to occupy a second volume greater than the first volume so that the upper surface is deformed vertically in order to raise the layer of granular medium, and vice versa;   the device being configured so that the lower surface remains substantially horizontal in the first and second configurations in order to maintain the device in position in the granular medium;   the device further being configured to switch from the first or the second configuration to a third configuration in which the lower surface of the envelope is vertically deformed for allowing the device to ascend through the granular medium.   
     
     
         17 . The device according to  claim 16 , wherein, in the third configuration, the inflatable element is inflated to a third volume greater than the second volume so as to elevate the edges of the envelope for allowing the device to ascend through the granular medium. 
     
     
         18 . The device according to  claim 16 , further comprising an additional inflatable element positioned below or embedded in the lower surface of the envelope and a pressurized fluid generator for inflating the additional inflatable element with a fluid, wherein in the third configuration said additional inflatable element is inflated so as to elevate the lower surface to allow the device to ascend through the granular medium. 
     
     
         19 . The device according to  claim 16 , wherein the envelope is leak-tight, so as to impede the passage of the granular medium therethrough. 
     
     
         20 . The device according to  claim 16 , wherein the injection device comprises at least one feeding pipe comprising a first portion adapted to receive a fluid and a second portion connected to the inflatable element, the first portion and the second portion being connected to each other by a bend, so as to prevent kinking of the feeding pipe between the first and the second portion. 
     
     
         21 . The device according to  claim 16 , further comprising at least one conduit between the injection device and the inflatable element, and a release device comprising a pressurized fluid generator and at least one outlet configured to inject the pressurized fluid into the granular medium so as to generate proximate to the conduit a mixture of fluid and granular medium, in order to enable the conduit to move into the granular medium as the device ascends or descends therethrough. 
     
     
         22 . The device according to  claim 16 , further comprising a burying device comprising a pressurized fluid generator and at least one outlet configured to inject the pressurized fluid into the granular medium below the lower surface of the envelope so as to generate a flow of a mixture of fluid and granular medium, in order to enable the burying of the device. 
     
     
         23 . The device according to  claim 21 , wherein the or each outlet comprises a pair of nozzles. 
     
     
         24 . The device according to  claim 23 , wherein the angle between the nozzles is 180°. 
     
     
         25 . The device according to  claim 16 , further comprising at least one pressure sensor. 
     
     
         26 . The device according to  claim 25 , wherein at least one pressure sensor is proximate to a central area of the upper surface and at least one pressure sensor is located proximate to a peripheral area of the lower surface. 
     
     
         27 . The device according to  claim 16 , further comprising a measuring device for measuring the height of the layer of granular medium above the device, the measuring device comprising at least one pressure sensor. 
     
     
         28 . The device according to  claim 27 , wherein the measuring device comprises:
 at least one bag located near or in the envelope, the or each bag being connected to a pressurized gas generator and comprising a pressure sensor configured to measure the pressure in the bag, and   a computing unit configured to calculate the height of the layer of granular medium based on the pressure sensor measurement and a calibration curve.   
     
     
         29 . The device according to  claim 28 , wherein the at least one bag located above the upper surface. 
     
     
         30 . The device according to  claim 16 , wherein the envelope comprises a first sheet forming the lower surface and having a first area, and a second sheet forming the upper surface and having a second area, said first and second sheets being joined together along their edges so as to form the internal volume, and wherein the second area is equal or greater than the first area. 
     
     
         31 . A method of deforming a layer of granular medium, the method comprising burying at least one flexible envelope comprising a variable internal volume at a predetermined depth in the granular medium, and varying the internal volume of said envelope between a first volume and a second volume greater than the first volume so as to raise or lower the layer of granular medium above the envelope. 
     
     
         32 . The method of deforming a layer of granular medium according to  claim 31 , wherein burying comprises: injecting a fluid into the granular medium below a lower surface of the envelope, so as to generate a flow of a two-phase mixture of fluid and granular medium in order to enable the burying of the envelope in the granular medium. 
     
     
         33 . The method of deforming a layer of granular medium according to  claim 31 , further comprising measuring a parameter of the granular medium by at least one sensor, and wherein the variation of the internal volume during varying the internal volume is controlled by a machine learning algorithm trained on said parameter.