Treeroot sha ed anc ors

In an engineering breakthrough, researchers discover tree root-like structures are stronger than traditional anchors

BYUSHA RAMANUJAM ARVIND

arure's skyscrapershaveJong intrigued geotechnique expert Dr Pierre Rognon,particularly the innate capacity of trees to stay anchored through varying weatherpatternsandi.ndiversesoilsystems.

Takinginspirationfrom theefficacyof its complexroot system,DrRognonis leadingaworld-firstSydneyUniversitystudy on thepullour capacityof treeroot-like anchorsfor applications ind1efieldof civil engineering.

Withaninterest in soil srabiliry,structural dynamics and earthquakeengineering, Indian researcherShivakumarAtbani,who sharesDrRognon's fascination for tree roots,hasrecentlyjoinedd1e study.

Preliminaryinvestigations at theSchool of Civil Engineering'sparticles and grains laboratory revealroot-like strucrurescould provide greater stabilitywhilealsobeing morecost effective toproduce.

The researchers have found d1at anchors modelled onthefractal-shaped rootsof trees required much less material tobuild, makingthem morecost-effective compared to traditional shaped anchors.

Their findingswill have far reaching implications for me constructionindustrr.

Transmissiontowers,offshoreoil rigs utilitypoles, submerged pipelines aswell as tunnels,whichare highly dependent on effective soilanchoringstrategiescould be mademore stablewith fractal-shapedroot strucrures.

"Thequalityof anchoringis characterised by me pull-out capacity,FO,whichis me maximum tensileforce ananchorcan sustainbefore moving upward," said Dr Rognon,whoseresearch aims topredict conditions nnderwhichsoilmoves, including landslides or avalanches.

"\'i/e are me first to produced1etreeroot designand hopetouseour knowledge coconvertmeconceptinto engineering solutions.Wehavealreadyworkedout severalmodels topredict the pull-out capaciryof shallowanchorsin granular soils.The next step is toassessthe effectivenessof different fractalgeometries when used invariousshallowdepths inthe soil,"he told Tndia11Link.

"Pull-our capacity is governed by the weightof mesoilthatwould be mobilised

,, Anchors modelled on the fractalshapedroots oftrees required much less material to build, making them more cost-effective compared to traditional shaped anchors ,, when tl1eanchor moves upward Thisiswhy even small trees planted in shallowsoilcan be very difficult to uproot wimouttheproper equipment,"Dr Rognon explained.

LikeRognon,Ad1ani developed a love for gardening asa schoolboy. Hisgrandmother, a schoolteacher inHattaragi,wasa towerof inspiration.

"Nature hasso many tlungswhichwecan explore,"saidArna.tu,whohasaBachelor of CivilEngineeringfrom theBasaveshvara Engineering CoUege,Bagalkoc and a MasterofTechnology (SoilMechat1.ics and FoundationEngineering) from meSV National Instirute of TechnologySurat.

"Treesarea great exampleof adapting toadverseconditionslikewindloading. If youexamine tree rootscarefully,you will observe that thoseon awindward side developdeeplyand profusely,offering natural resistance.Likewise,in sloping terrain,roots are strongerwheresoil is naturallyweak.'i,'.qhat fascinated mewas, though theroots of smallplants arenot deep, sometimes itwas very hard topull mem outand weneeded thehelp of some tools ro uprootit complete.ly,"he added. lncorporatingbranchingand tortuosity, the study is closely lookingat,vays ro improve anchor capacities by integrating novelstrategieswim numericalmodelling.

AccordingtothePhD student,part of me breakthrough in biomimicry comeswith realisingmatsoilisnot concrete.

"Roots arenor homogeneouslike steel. Sometimes soil canhold metrees very firmlyand canoffer enormousresistance for uplift,"Athani said.

"\'Ylealsowant toformer explore design options and understandwhy somedesign shapesworkbener tooptimise ourresults," DrRognon clarified.Three-dimensional printing,currently unsustainable because of operational costs, is also in hissights.

Meanwhile,DrRognon'steamisworking with industrypartnerAnchoringRopeand RiggingPtyLtdtodevelop uniqueanchors for georechnical applications.

"Researchin mis areaof construction is vital toprovidinginnovative solutions andwe are delighted to have commenced workingwid1 d1e University of Sydney civil engineers," aspokespersonfor thecompany said.