Apparent Value of ch Determined from Field Bahavior of Two Soft Clay Deposits in Southern Vietnam

摘要

Apparent value of horizontal coefficient of consolidation, denoted c_(h(ap)) in this paper, is determinedrnfrom field data for two soft clay deposits in Southern Vietnam improved by vertical drain method. In order tornevaluate c_(h(ap)), Asaoka’s observational method is applied to settlement data obtained by extensometers andrnsettlement plates. The values of c_(h(ap)) at the two sites are from 40cm~2/d to 80cm~2/d with PVD spacing from 0.85m torn1.5m. Then, they are compared with vertical coefficient of consolidation c_v given by laboratory consolidation test.rnThe comparison shows that c_(h(ap)) is 2 to 2.5 times as much as c_v. Furthermore, c_h values are evaluated from c_(h(ap)) byrnusing Barron’s and Hansobo’s approximations. Values of ch are found to be 3 to 7 times as much as c_v.