Structural Stability Evaluation, Pokegama Dam.
Abstract
The 77-year old surface concrete of Pokegama Dam is generally in excellent condition. The average unconfined compressive strength of the concrete above approximately el 1264 is 4900 psi. The remainder of the concrete has a compressive strength at least as low as 1360 psi. The monoliths of Pokegama Dam are adequate in their resistance to overturning, sliding, and base pressures if the clay seams in the foundation are investigated and found to be of such an extent and nature that stability and underseepage at the seams are not a problem. Except for the clay seams, the foundation material under Pokegama Dam appears to be competent and adequate. The small amount of deteriorated concrete, mainly at the downstream ends of the piers should be repaired in order to prevent the entrance of water into cracks which will stop the freezing and thawing deterioration and eliminate the need for more costly repairs in the future. The foundation is variable with clay seams present in core P-P4. It is recommended to: (a) Determine the extent of clay seams beneath the dam in the area of pier 4 by drilling upstream, between, and downstream of the piers. (b) Evaluate the effect of the clay seams on the structural stability of the dam piers. (c) Take remedial action necessary to insure that the possibility of any seams washing out is reduced to an acceptable level. The right embankment of the dam should be investigated for voids and imperviousness. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1980
- Accession Number
- ADA090612
Entities
People
- Carl E. Pace
- G. Sam Wong
- Roy L. Campbell