Methods of analyzing field consolidation data from areas with and without vertical drains are presented. All methods analyze field data independently of laboratory data. Settlement data from areas having vertical drains can be analyzed by three different techniques toyield values of the apparent coefficient of consolidation and the ultimate settlement for foundation clay. Analysis of piezometer data yields values of apparent coefficient of consolidation by a separatetechnique. Data from areas without drains can be analyzed for similar parameters. All methods involve the use of terzaghi's theory of consolidation or barron's equal strain theory for areas with verticaldrains. These theories are appropriate for analysis of most clay deposits. The techniques are illustrated and results from their use onthe consolidation of varved clay beneath the approach fills of the putnam bridge are presented. These techniques were used in analyzingthe data from 49 settlement platforms and two piezometer groups of this project. The results show interesting phenomena that should be explored further with data from other sites. This paper appears in transportation research record no. 1277, Modern geotechnical methods:instrumentation and vibratory hammers 1990.
Abstract