2003 Fiscal Year Final Research Report Summary
LARGE-SCALE TESTS OF LEACHATE THROUGH COMPOSITE LINER DUE TO GEOMEMBRANE DEFECTS
| Project/Area Number |
13650545
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Geotechnical engineering
|
|---|
| Research Institution | Saga University |
|---|
Principal Investigator |
CHAI J.-c. Saga University, INSTITUTE OF LOWLAND TECHNOLOGY, Associate Professor, 低平地研究センター, 助教授 (20284614)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MIURA N Saga University, INSTITUTE OF LOWLAND TECHNOLOGY, Chief Researcher, 軟弱地盤研究所, 佐賀大学名誉教授(主任研究員) (00035073)
|
|---|
| Project Period (FY) |
2001 – 2003
|
| Keywords | COMPOSITE LINER / ADVECTION-DEFFUS ION TRANPORT / MSW / FLOW RATE / LARGE SCALE MODEL TEST / DEFECT ON GEOMEMBRANE |
|---|
| Research Abstract |
Large-scale model tests of leachate through composite liner due to geomembrane defects were conducted. The effects of effective overburden pressure (p) (excludes the pressure from leachate) on the leachate flow rate and the mechanism of leachate migration are investigated. The model composite liner consisted of a 0.36 m thick soil layer and one layer of geomembrane. The diameter of the model is about 1.2 m. The equipment used is capable to apply up to 200 kPa effective overburden pressure to the model composite liner. Test and analysis results indicate that increasing p value on geomembrane reduces the leachate flow rate significantly. This reduction is mainly due to the reduction of geomembrane/soil interface transmissivity (T). After the leachate flow test, by measuring the concentration of target ion, it is confirmed that there was flow at geomembrane/soil interface. Comparing the measured data with predicted values using existing equations shows that assuming a perfect contact condition at geomembrane/oil interface is not applicable, in practice. Giroud et al.'s (1997) empirical equations for good contact (imperfect) condition can provide a reasonable prediction of the flow rate through ' a defect in geomembrane of composite liner under lower effective overburden pressure (close to zero). -Based on the test results of this study, Giroud et al.'s (1997) equations are modified to consider the effect of effective overburden pressure. Using Rowe's (1998) equations, T values are back-evaluated from the test results, which provide a useful reference for estimating T value.
|
