values are half again as large as the measured values. 



These discrepancies suggest that calcareous oozes are quite 

 different from terrestrial soils, and that standing empirical relationships 

 for the prediction of soils engineering behavior may not apply. 

 Suggestions can be made regarding reasons for such discrepancies. 

 First, the relationships for predicting Cc based on initial void 

 ratio, e , and water content, w, yield values which are too high 

 because much of the water filled voids are within the Globigerina 

 tests and do not substantially enter into the soil compressibility 

 at the loadings used. That the tests do not undergo substantial 

 crushing in the natural specimen is substantiated by a grain size 

 determination made at the conclusion of the second consolidation 

 test; no substantive change in the grain size curves, before and 

 after, could be detected, indicating little crushing. The relationships 

 for predicting C^ based on liquid limit, w , yield values which 

 are lower than those measured. Conjecture as to why will be deferred 

 until further testing evaluates the magnitude of error due to sample 

 extrusion around the porous stone; i.e., possibly the observed 

 lack of agreement is due to testing error. 



Time Rate of Primary Consolidation. The time rate of consolidation due 

 to each increment of load is obtained by, in effect, comparing the specimen 

 height-change-versus-time curve (for example, see Appendix) with a theor- 

 etically-derived curve of volume change versus time as a function 

 of the hydrostatic lag. This comparison is achieved through a curve 

 fitting process and is quantitatively described by an empirical 

 coefficient of consolidation, c^ (see Reference 33, pp. 238-242). 

 The test data obtained for vertical effective stresses, Ov» less 

 than 96 kPa (2000 psf) were not amenable to these curve fitting 

 procedures. Similar behavior for calcareous ooze has been noted 

 elsewhere [10]. The coefficient of consolidation, for a equal 

 to and greater than 96 kPa, ranged from 0.003 to 0.021 cm ^ /sec. 



Time Rate of Secondary Consolidation. After the conclusion 



of primary consolidation, the specimen height change as a function 



of time is described quantitatively by the coefficient of secondary 



consolidation, C , 



" AH 



C = - — ^^ (Reference 38, p. 421) 



a H X Alog. t 



where AH = slope of the secondary consolidation portion of the 

 Alog. t height change versus log time curve (for example, 

 see Appendix) , 

 H = specimen height at the end of primary consolidation. 



Measured values of C ranged between 0.0015 and 0.009, with values 

 generally increasing with vertical effective stress. When compared 

 to data from Reference 37 (p. 7-3-15), the above C data suggest that 



10 



