Upgrading of Matahina Dam for Foundation Fault Displacement

摘要

Because it is difficult to mitigate the risks associated with fault displacements in a dam foundation, it is widely preferred in engineering practice to avoid siting dams over active surface faults. Occasionally this cannot be avoided and a number of dams have been designed arid Built 16 accommodate surface fault displacements in their foundations. This paper presents a case history of upgrading of a large dam, the Matahina Dam in New Zealand, to accommodate potential surface fault displacements in the dam foundation. A conservative and robust design, based on well established engineering principles and multiple lines of defense, was developed and constructed so that the dam will withstand the maximum earthquake that could affect it without uncontrolled release of the reservoir. This paper describes the dam, the seismic hazard, the design criteria, and the design and construction of the dam modifications.