Bramhoek Dam

Type: Roller Compacted Concrete Dam (RCC)
Construction Date: April 2008 - August 2011
Location: Ladysmith KwaZulu Natal, South Africa
S 28.311635° E 29.579374°
Bramhoek Dam, situated below the mountains near Ladysmith, Kwa-Zulu Natal, is 39m high Roller Compacted Concrete Dam (RCC), with a 335m crest Length. The dam structure forms the lower reservoir of the Ingula Pumped Storage Scheme. Structure includes a free crest spillway with a crest length of 40m over RCC.

Bramhoek dam was constructed by Bedford/Bramhoek Dams Joint Venture (BDJV) and has a capacity of 26.7 million m³ and an active storage volume of 19.1 million m³.

Bramhoek Dam Instrumentation consists of the following:
  • Vibrating Wire Strain Gauges in and around the Outlet-Tunnel measuring RCC strain.
  • Vibrating Wire Long Base Strain/Jointmeters measuring over induced joints.
  • Vibrating Wire Thermometers measuring temperature.
  • Thermistors measuring temperature.
  • Vibrating Wire Foundation Piezometers for measuring pore pressure.
  • Eight sets of Vibrating Wire 3-D Crackmeters measuring three-dimensional movement on the crest.
  • Eight Vibrating Wire Tilt-meters measuring tilt.
  • Vibrating Wire Transducer measuring seepage

Instruments installed in and around the Dam Embankment are intended to monitor:
  • Tilt of the Dam;
  • Measuring movement over the induced joints;
  • Stresses and strain of the concrete;
  • Total downstream seepage;
  • Pore pressure build-up in foundation;
  • Lake level water height.

Installed Instruments Specification:
Seepage (Dam)
• Geokon Vibrating Wire Transducers Vented Model 4580
Piezometers (Foundation, crump weir, lake level)
• Geokon Vibrating Wire Model 4500S
• Geokon Vibrating Wire Model 4500AL (V)
Joint Meter (Main Embankment)
• Geokon Vibrating Wire Model 4400
Strain Gages (Main Embankment)
• Geokon Vibrating Wire Model 4210/4200/4202
Tilt Meter (Crest)
• Geokon Vibrating Wire Model 6350
3D Crack (Crest)
• ITMsoil J3 - Vibrating Wire Tri-axial Joint meter
Temperature Gauge (Main Embankment)
• Geokon Vibrating Wire Temperature Sensor Model 4700
Data Acquisition System CR800/1000 (Valve House)
• Geokon Micro-1000 Data logger Model 8021
• Geokon Multiplexer (MUX) Model 8032

Designers: Steward Scott Incorporated (SSI), Arcus Gibb and Knight Piésold

Consulting Engineers: Braamhoek Consultants Joint Venture (BCJV) comprises three of the country's mayor consulting firms bramhoek_damly SSI, Arcus Gibb and Knight Piésold

Contractors: Concor Roads & Earthworks, Wilson Bayly Holmes-Ovcon (WBHO), Edwin Construction and Silver Rock (BDJV)

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