A comparative study on the horizontal coefficient of consolidation (Cr) obtained from lab and field tests

• Main Author: Trần, Quỳnh Giao
• Other Authors: Nguyen, Tien Dung
• Format: Theses and Dissertations
• Language: English
• Published: 2020
• Subjects: Nền đất yêu > Cải tạo; Hệ thống thoát nước; 621
• Online Access: http://repository.vnu.edu.vn/handle/VNU_123/93287
• Institution: Vietnam National University, Hanoi

When a soft ground is improvedby PVDs, consolidation takes place under the condition of drainage in both horizontal and vertical directions. Naturally, horizontal coefficient of consolidation (cr) is larger than the vertical coefficient of consolidation (cv) by a factor of 3 to 5. Thecvvalue is commonly interpreted from consolidation test using incremental loading method [1].However, up to date, there have not been any similar standards for the consolidation test with horizontal drainage (using incremental loading method). The key goals of the research are: (1) determine the most reliable methods among the proposed methods for determining the horizontal coefficient of consolidation (cr) in the literature; (2) determine correlations between crvalues obtained from central drain (CD) test and peripheral drain (PD) test; (3) determine correlations between vertical coefficients of consolidation (cv) and radial crfor a number of test sites in Vietnam.A desk study is carried out to secure the following: (1) a literature review on equipment used for the test and existing methods used to evaluate the crvalue; (2) the thesis using data collected from the following sources literature review and test site in Vietnam.Overall, Themost reliable methods for determining the horizontal coefficient of consolidation (cr)is non-graphical method and the root t can be usedto determine theradial (horizontal) coefficient of consolidation (cr). cr,PDis less than the cr,CDby a factor of0.32to 0.64from intact samples and 0.33 to 0.58from remoldedsamples.crPDis larger than the cvby a factor of 0.90 to 2.33,crCDislargerthan the cvby a factor of 2.14 to 5.12from intactsamples.crPDis less than the cvby a factor of 0.35 to 1.01,crCDisless than the cvby a factor of 0.41 to 0.82from intact samples.