WSP10308

• File Number: 8449
• Description: Platte River Studies
• State: CO
• Basin: South Platte
• Date: 3/23/1993
• Author: Smith Geotechnical
• Title: Design Report Peterson Lake Dam
• Water Supply Pro - Doc Type: Publication

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TABLE 3
CALCULATED FACTORS OF SAFETY

Joint Bond Based On Am~le Of Friction OnlY
STA. CASE FOUNDATION TENSILE SLIDING
SLIDING STRENGTH F.S.BETWEEN
F.S, RQD . LIFT LIFTS
(psI)
1+26 USUAL 1.66 0 1.46 . 66'
UNUSUAL - - -
EXTREME 1.23 6 1.12 . 66'

Foundation rock cohesion = 0 psf, Friction Angle = 46.
Ree cohesion = 0 psi, Friction Angle = 46.
Vertical &. Horizontal Earthquake Coefficient = O.lg

TABLE 4

MINIMUM REQUIRED FACTORS OF SAFETY
LOADING LOCATION MINIMUM MINIMUM
COMBINATION FACTOR OF FACTOR OF
SAFETY SAFETY
COHESION=O.O
USUAL FOUNDATION SLIDING 4,0 1.5
OVERTURNING 1.5 -
COMPRESSIVE STRESS 3,0 -
SLIDING BETWEEN LIFTS 3.0 1.5
UNUSUAL FOUNDATION SLIDING 2.7 1.2
OVERTURNING 1.3 -
COMPR!!:SSIVE STR!!:SS 2.0 -
SLIDING BETWEEN LIFTS 2,0 1.2
!!:XTREME FOUNDATION SLIDING 1.3 1.0
OV!!:RTURNING 1.1 -
COMPRESSIVE STRESS 1.1 -
SLIDING BETWEEN LIFTS 1.1 1.0

d. Crack Analysis. The potentlsl for cracking In the darn was analyzed
using the simplIfied method outlined In "Thermal Analysis For RCC-A Practical
Approach", by Steve Tatro and E, Schrader, from the specialty conference, ROLLER
COMPACTED CONCRETE III, San Diego, CalIfornia, Feb, 2-5. 1992, and CONTROL OF
CRACKING IN MASS CONCRETE STRUCTURES, Bureau of Reclamation, 1981, and
Bureau of Reclamation Monograph No. 34.

The adiabatic rise In temperature of the concrete Is the major variable that
controls the cracking In the dam. The average temperature at the site and the
temperature of the aggregate Is also Important to control. These will be
expected to be better than at most locations due to the high altitude of the

PAG!!: 6
Peterson Lake Darn Design Report