Geotechnical, geophysical, and geodetic surveys conducted by Geodynamics Research Centre (LLC CGI) of Russia over the last few years has shown that as the right slope of the dam foundation is weaker than the left, the residual deformation on the right slope has increased, and as a result the dam has begun to tilt to the right side.
During high water levels in the reservoir, there is a shortage of stress in the left bank, leading to the appearance of weakened zones in the massif and the development of cracks.
The loading and processing of the reservoir and accordingly the loading and unloading of the foundation will in future reduce the bearing capacity of the foundation contact zone, increase deformations in the dam and the development of cracks, and this could eventually lead to an accident, according to a recent report on the present conditions of the abutments of the dam. Geophysical studies have shown that such anomalous zones are more likely to be on the left bank. As such, the situation requires urgent assessment of appropriate measures to stabilise the structure and ensure the long-term reliable operation of the dam and its foundation.
The client requires the development of a policy paper, as well as a number of stakeholder workshops, to help understand better the available the options, and to identify the optimum approach, as well as secure some commitment for action from key stakeholders.
Specifically, the scope of services to be undertaken are as follows:
• a synthesis and analysis of data on the present-day state of the rock massif at the dam’s foundation;
• additional investigations aimed at specifying engineering-geological conditions of the rock massif at the foundation;
• elaboration of the arch dam foundation model;
• inspection of the state of the dam;
• elaboration of the computational models of the dam-foundation interface system;
• numerical modelling;
• design of rock mass strengthening measures for the Enguri dam foundation and abutments to ensure its future reliable operation;
• design of the rehabilitation, and any further improvements to the field monitoring system; and,
• assessment of the results,and project implementation strategies.
The assignment is expected to take at least 12 months, beginning in September this year.
The full tender notice and a full description of the assignment, (including detailed technical and financial requirements, information on the lots, eligibility and qualification requirements, contract start date and planned contract duration, and response requirements), can be accessed free of charge on the EBRD Client E-Procurement Portal (ECEPP).
Prospective participants can access the procurement tender via the website (see details below).
Participants must use the ECEPP message centre for communication with the client.
For further information, contact: Malkhaz Tskvitishvili,
8, Anna Politkovskaya Street
Tel: +995 32 218 9669