?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=DEM+study+on+the+mechanical+behaviours+of+methane+hydrate+sediments%3A+hydrate+growth+patterns+and+hydrate+bonding+strength&rft.creator=Cheng%2C+YP&rft.creator=Yu%2C+Y&rft.creator=Xu%2C+X&rft.creator=Soga%2C+K&rft.description=Natural+methane+hydrate+soil+sediments+attract+worldwide+interest%2C+as+there+is+huge+commercial+potential+in+the+immense+global+deposits+of+natural+gas+hydrate+that+lies+under+deep+seabeds+and+permafrost+regions.+However%2C+the+geomechanical+behaviour+of+methane+hydrate+soil+is+poorly+understood.+In+this+study%2C+Discrete+Element+Method+(DEM)+was+employed+to+provide+insights+into+the+mechanical+behaviour+of+hydrate-bearing+sediments+with+different+hydrate+patterns+in+the+pores%3A+the+pore-filling+case+and+the+cementation+case.+A+series+of+drained+triaxial+compressional+tests+were+performed%2C+and+the+results+were+analyzed+in+terms+of+stress-strain+response+and+volumetric+response.+In+both+pore-filling+and+cementation+cases%2C+the+presence+of+hydrates+caused+an+increase+in+the+strength+and+dilative+tendency+of+the+simulated+hydrate-bearing+soil+samples%2C+and+the+strength+and+dilation+both+increased+with+hydrate+saturation+(or+amount+of+hydrates+in+the+pores).+In+addition%2C+at+the+same+hydrate+saturation%2C+the+cementation+case+showed+higher+values+of+strength+and+dilation+than+the+pore-filling+case.+In+the+cementation+case%2C+two+typical+hydrate+growth+patterns+were+considered%3A+soil+surface+coating+(hydrates+form+around+the+grain+surface)+and+soil-soil+contact+gathering+(hydrates+preferentially+form+at+the+grain+contacts).+Results+showed+that+hydrate+growth+patterns+greatly+influenced+the+mechanical+behaviour+of+the+simulated+hydrate-bearing+samples%2C+especially+when+the+bonding+strength+and+hydrate+saturation+were+increased.+In+both+patterns%2C+strength+and+dilation+were+enhanced+as+bonding+strength+increased%2C+and+the+enhancement+was+greater+in+the+soil-soil+contact+model+than+in+the+soil+surface+gathering+model.+At+high+hydrate+saturation%2C+as+bonding+strength+increased%2C+a+larger+axial+strain+was+needed+to+reach+the+peak+strength%2C+and+the+development+of+dilation+was+delayed.&rft.date=2014-08-01&rft.type=Proceedings+paper&rft.language=eng&rft.source=+++++In%3A++Proceedings+of+the+8th+International+Conference+on+Gas+Hydrates+(ICGH8-2014).++++%3A+Beijing%2C+China.+(2014)+++++&rft.format=text&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1466182%2F1%2F201407_Yuetal_ICGH8_Beijing_Bonding%2520Strength.pdf&rft.identifier=https%3A%2F%2Fdiscovery.ucl.ac.uk%2Fid%2Feprint%2F1466182%2F&rft.rights=open