|
|
| 說明 | 397 p |
| 附註 | Source: Dissertation Abstracts International, Volume: 61-12, Section: B, page: 6607 |
| Professor in charge: Victor N. Kaliakin |
| Thesis (Ph.D.)--University of Delaware, 2001 |
| The purpose of the present study was: (1) To develop a realistic constitutive model for Geogrid reinforcement that accounts for general time-dependent response, and (2) To gain insight into the time-dependent behavior of geosynthetically reinforced soil walls primarily under non-failure conditions |
| Based on the results of high quality experiments, and having investigated the validity of the isochrone concept, the first objective was realized. The constitutive model developed is limited to non-failure load levels and to geosynthetics for which relaxation values obtained from creep isochrones are in good agreement with experimentally measured values |
| The second objective was realized by mathematically modeling a laboratory-instrumented wall with cohesive backfill and then performing numerical parametric studies of the wall. In each of these studies the number of assumptions associated with the modeling process was minimized. In all cases, the soil-wall-reinforcement system was treated as a boundary value problem and analyzed using the finite element method |
| The results of these analyses indicated that: (1) Failure to include the time-dependent response of the backfill soil may significantly underestimate displacements in the soil mass and strains and stress in the reinforcement. (2) Use of a time-independent, quasi-linear elastic (“hyperbolic”) material idealization overestimates displacements in the soil mass and strains and stress in the reinforcement. (3) During sustained loading 1000 hours in duration, the deformation of the backfill soil and timber facing rather quickly became negligible, as the viscoplastic strain rate went to zero. Consequently, the reinforcement was essentially in a state of relaxation. The practical ramifications of this finding are a possible decrease in creep reduction factors associated with typical design procedures involving geosynthetically reinforced soil structures |
| School code: 0060 |
| 主題 | Engineering, Civil |
| 0543 |
| ISBN/ISSN | 0493066217 |
