University of Porto

UPHS. Numerical Modelling

AN INNOVATIVE UNDERDROUND POWER SHEME

Numerical Modeling

Bruno Correia

Luis Leal

L. Ribeiro e Sousa

University of Porto, Portugal

University of Porto

UPHS. Numerical Modelling

• This presentation is related to an UPHS innovative hydroelectric scheme in a small island, Portugal.

• Also presents numerical analyses performed considering FEM models developed at University of Porto.

University of Porto

UPHS. Numerical Modelling

• The UPHS system is equipped with reversible units with a differential elevation of about 450m between an upper tunnel and a lower storage tunnel.• The repowering included the sequence of underground works:

– 5.2km tunnel located at upper level

– A gallery for storage with a total capacity of 40 000m3

– A cavern pumped station

– An auxiliary gallery

University of Porto

UPHS. Numerical Modelling

FUNCHAL

MACHICO

de

LOCALIDADE

APROVEITAMENTOS HIDROELÉCTRICOSDA REGIÃO AUTÓNOMA DA MADEIRA

University of Porto

UPHS. Numerical Modelling

• UPHS Scheme

University of Porto

UPHS. Numerical Modelling

• Upper reservoir– 5200 m– 40000 m3

University of Porto

UPHS. Numerical Modelling

• Lower reservoir– 1200 m– 40000 m3

University of Porto

UPHS. Numerical Modelling

• Pumped Station

University of Porto

UPHS. Numerical Modelling

• Auxilliary tunnel

University of Porto

UPHS. Numerical Modelling

• Geomechanical characterization

– ZG1 – ZG2

University of Porto

UPHS. Numerical Modelling

• Lower reservoir

Túnel km inicial km final Extensão (m)

Frente 1 0+017,500 0+473,000 475,50

Frente 2 1+153,000 1+536,000 340,50

Frente 3 1+722,000 2+598,000 198

Frente 4 2+681,000 3+406,500 36,50

Frente 5 2+681,000 3+406,500 112

Frente 6 2+681,000 3+406,500 37,50

Total 1200

University of Porto

UPHS. Numerical Modelling

• Auxiliary tunnel

University of Porto

UPHS. Numerical Modelling

• Volcanic materials

Compact basalt Breccias

University of Porto

UPHS. Numerical Modelling

• FEM models for lower reservoir– Phase2 – Rocscience– 4 stages

Stages

University of Porto

UPHS. Numerical Modelling

• 3 types of volcanic formations

University of Porto

UPHS. Numerical Modelling

• Conclusions

University of Porto

UPHS. Numerical Modelling

• Analysis of different shapes

University of Porto

UPHS. Numerical Modelling

• Total displacements

University of Porto

UPHS. Numerical Modelling

• Pumping station– High - 26 m; – width - 12 m; – length - 44 m

University of Porto

UPHS. Numerical Modelling

• FEM models

– 11 stages

University of Porto

UPHS. Numerical Modelling

• Analysis of the structural behaviour

University of Porto

UPHS. Numerical Modelling

– Horizontal displacements at the walls

– Settlements at surface

University of Porto

UPHS. Numerical Modelling

• Safety factor

University of Porto

UPHS. Numerical Modelling

• Generalized forces

– a) N; b) T; c) M

University of Porto

UPHS. Numerical Modelling

• 3D model• Plaxis

University of Porto

UPHS. Numerical Modelling

• Upper tunnel

University of Porto

UPHS. Numerical Modelling

• 5200 m – single TBM

University of Porto

UPHS. Numerical Modelling

• Fall of basalt blocks

University of Porto

UPHS. Numerical Modelling

• Geometry

University of Porto

UPHS. Numerical Modelling

• Thank You