Upper Kothmale Tunnel supporting methods

8/8/2019 Upper Kothmale Tunnel supporting methods

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UpperUpper KothmaleKothmale Power PlantPower Plant

Presented by: M.S.M.Presented by: M.S.M. ShamihShamih

UniversityUniversity of Moratuwaof Moratuwa


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I am Going to Cover . . .I am Going to Cover . . .Tunnel Supporting MethodsTunnel Supporting Methods

Site SafetySite SafetyConclusionConclusion

AcknowledgementAcknowledgement


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Tunnel Supporting MethodsTunnel Supporting Methods

Shotcrete OperationShotcrete Operation

Rock Bolt FixingRock Bolt Fixing Steel supportsSteel supports

All Ground Fastening (AGF) MethodAll Ground Fastening (AGF) Method


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Shotcrete OperationShotcrete Operation Shotcrete is a mixture of cement, chip metal, sand, dustShotcrete is a mixture of cement, chip metal, sand, dust

,water and admixtures,water and admixtures

Shotcreting is done using shotcrete machineShotcreting is done using shotcrete machine

Apply soon after excavation and removal of unsteadyApply soon after excavation and removal of unsteady

rockrock

Wet and Dry processes are two methods of applyingWet and Dry processes are two methods of applying

ShotcreteShotcrete

Wire mesh is provided to strengthenWire mesh is provided to strengthen


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Shotcrete OperationShotcrete Operation

cont.cont.


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Rock Bolt FixingRock Bolt FixingRock bolt is a steel rod, which consists ofRock bolt is a steel rod, which consists of

a plate and a bolta plate and a boltUsed for stabilizing loosen rock with theUsed for stabilizing loosen rock with the

help of bed rockhelp of bed rock


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Steps of Rock Bolt FixingSteps of Rock Bolt FixingLocations Mark

Drilling

Cleaning

Insertion of Rock Bolts

Pumping Mortar

Tightening of plate and nut


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Steel SupportsSteel SupportsSteel supports are used when theSteel supports are used when the

ground conditions are adverseground conditions are adverseIt should be placed immediately afterIt should be placed immediately after

tunnel excavationtunnel excavation

They are placed by using Drill jumboThey are placed by using Drill jumboFixed at specified intervals beforeFixed at specified intervals before

applying shotcreteapplying shotcrete


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Steel Supports cont.Steel Supports cont.


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All Ground FasteningAll Ground Fastening

MethodMethodThis is kind of pipe roof umbrella systemThis is kind of pipe roof umbrella system

This method is applied at the entry and theThis method is applied at the entry and theexit of the tunnelexit of the tunnel

Increases the ground supporting capabilityIncreases the ground supporting capability

of tunnels crownof tunnels crown

It is possible to improve the ground aroundIt is possible to improve the ground around

the pipes (by injecting silicate resin)the pipes (by injecting silicate resin)


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All Ground FasteningAll Ground Fastening

Method Cont.Method Cont.

Umbrella structure of

tunnel crown

AGF pipes

Silicate Resin

Structure


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Combination of SupportsCombination of Supports


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Site SafetySite SafetyEvery one enter to the tunnel must wearEvery one enter to the tunnel must wear

helmets, boots and safety jacketshelmets, boots and safety jackets

The person, entering to the tunnel, shouldThe person, entering to the tunnel, should

mark his name on the signboardmark his name on the signboard

At the time of drilling and charging everyAt the time of drilling and charging every

one should wear ear plug and dust maskone should wear ear plug and dust mask

The labors should wear eye protectors andThe labors should wear eye protectors and

gloves according to the applicationgloves according to the application


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Site Safety Cont.Site Safety Cont.


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ConclusionConclusionOur country need many more vastOur country need many more vast

projects such thisprojects such this

We have to use Modern constructionWe have to use Modern construction

technologiestechnologies

Local contractors should promote toLocal contractors should promote tohandle vast projectshandle vast projects


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AcknowledgementAcknowledgementDr. Lesley EkanayakeDr. Lesley Ekanayake

Dr. (Mrs.) C. JayasingheDr. (Mrs.) C. JayasingheDivision of Building Construction andDivision of Building Construction and

ManagementManagement

Staffs of Upper Kothmale HydropowerStaffs of Upper Kothmale HydropowerProjectProject

Our batch mates who undergone trainingOur batch mates who undergone training

in this projectin this project


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Questions?Questions?

Upper Kothmale Tunnel supporting methods

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