1992) . Thus the static stress increase is probably due more to the continued 

 nesting of the dolos armor layer. 



55. The static stress distribution given in Equation 3 includes the 

 measured maximum static stresses in each of the instrumented Crescent City 

 dolosse during the period from post-construction in February 1987 to July 

 1990. So the long-term increase in static stress during this period is in- 

 cluded in the distribution. Because it is not known if the mean static stress 

 increase is approaching an equilibrium value, no explicit modification for 

 long-term changes in stress is included in this design procedure. The 

 stresses in the prototype dolosse continue to be monitored yearly and an 

 adjustment factor for the time rate of change of stress will be incorporated 

 in Equation 10 if the stresses continue to increase. 



Tidal influences 



56. Melby and Howell (1989) showed preliminary results from correla- 

 tion analyses of sporadic static dolos moments versus tidal time series. The 

 low correlation coefficients from this analysis were inconclusive, although 

 the plots of tidal height and moments versus time indicated that the dolos 

 static moments were correlated with tide. The tidal response of a dolos that 

 is alternately dry and submerged is due to the reduction in self weight; the 

 submerged weight of a dolos with a specific gravity of S = 2.42 is only 



59 percent of the dry weight. The response of dolosse at or below the still- 

 water level to fluctuations in tidal height is therefore obvious. But the 

 Crescent City results apparently showed moment-versus-tide correlation for 

 dolosse that were high and dry, above the still -water level. More recent data 

 from the Crescent City dolosse have shown that this dry dolos quasistatic 

 response is not due to tidal fluctuations but is caused by concrete shrinkage 

 and swelling due to temperature variations throughout the day. This type of 

 straining does not induce stresses in the dolosse and is therefore not a 

 concern. 

 Pulsating response 



57. The maximum pulsating stress is a function of the design wave 

 height H , the exceedance probability E , and a wave stress constant k^ s 

 (Howell, Rhee, and Rosati 1990). The Rayleigh distribution, given in 

 Equation 17, best describes the Crescent City dolos pulsating response. 



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