Laboratory model tests on geosynthetics application for protecting the coastal cliff erosion

Most of the hydropower dams in Sweden were built before 1980. The present dam-safety guidelines have resulted in higher design floods than their spillway discharge capacity and the need for structural upgrades. This has led to renewed laboratory model tests. For some dams, even computational fluid dynamics (CFD) simulations are performed. This provides the possibility to compare the spillway discharge data between the model tests performed a few decades apart. The paper presents the hydropower development, the needs for the ongoing dam rehabilitations and the history of physical hydraulic modeling in Sweden. More than 20 spillways, both surface and bottom types, are analyzed to evaluate their discharge modeling accuracy. The past and present model tests are compared with each other and with the CFD results if available. Discrepancies do exist in the discharges between the model tests made a few decades apart. The differences fall within the range −8.3%–+11.2%. The reasons for the discrepancies are sought from several aspects. The primary source of the errors is seemingly the model construction quality and flow measurement method. The machine milling technique and 3D printing reduce the source of construction errors and improve the model quality. Results of the CFD simulations differ, at the maximum, by 3.8% from the physical tests. They are conducted without knowledge of the physical model results in advance. Following the best practice guidelines, CFD should generate results of decent accuracy for discharge prediction.

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Basic Study on Mechanism of Cave-in in Road through Laboratory Model Tests

International Journal of Highway Engineering ◽

10.7855/ijhe.2016.18.5.011 ◽

2016 ◽

Vol 18 (5) ◽

pp. 11-19 ◽

Cited By ~ 4

Author(s):

Gichul Kweon ◽

Sanglok Kim ◽

Seokwoo Hong

Keyword(s):

Model Tests ◽

Laboratory Model ◽

Basic Study

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A model test and numerical investigation on the shear deformation patterns of deep wall–soil–tunnel interaction

Canadian Geotechnical Journal ◽

10.1139/t06-088 ◽

2006 ◽

Vol 43 (12) ◽

pp. 1306-1323 ◽

Cited By ~ 8

Author(s):

Yong-Joo Lee ◽

Richard H Bassett

Keyword(s):

Finite Element ◽

Shear Deformation ◽

Urban Areas ◽

Shear Failure ◽

Model Tests ◽

Numerical Analyses ◽

Laboratory Model ◽

Failure Patterns ◽

Physical Tests ◽

Deformation Patterns

In congested urban areas, tunnel excavations have become necessary due to a lack of space. In many cases, such excavations are needed in areas adjacent to existing loaded piles. Therefore, a careful assessment of the wall–soil–tunnel interaction is required. These circumstances are relatively new, however, and only limited information is currently available. The complicated soil behaviour, particularly for the shear failure pattern between the wall and tunnel observed in both physical tests and numerical analyses, has not been clearly identified by other researchers. The authors have conducted laboratory model tests on an idealized granular medium using close-range photogrammetric techniques to measure detailed displacement patterns. The results have been compared with those from numerical analyses. This paper presents shear failure patterns for a number of geometries and shows good agreement between the physical tests and the finite element analyses.Key words: tunnel excavation, shear deformation patterns, wall–soil–tunnel interaction, model tests, photogrammetry, finite element analysis.

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Stability analysis of a copper tailings dam via laboratory model tests: A Chinese case study

Minerals Engineering ◽

10.1016/j.mineng.2010.10.014 ◽

2011 ◽

Vol 24 (2) ◽

pp. 122-130 ◽

Cited By ~ 34

Author(s):

Guangzhi Yin ◽

Guangzhi Li ◽

Zuoan Wei ◽

Ling Wan ◽

Guohong Shui ◽

...

Keyword(s):

Stability Analysis ◽

Model Tests ◽

Laboratory Model ◽

Tailings Dam ◽

Copper Tailings ◽

Chinese Case

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Transition of soil friction during suction pile installation

Canadian Geotechnical Journal ◽

10.1139/t02-054 ◽

2002 ◽

Vol 39 (5) ◽

pp. 1118-1125 ◽

Cited By ~ 7

Author(s):

Y Cho ◽

S Bang ◽

T Preber

Keyword(s):

Soil Properties ◽

Friction Angle ◽

Soil Strength ◽

Model Tests ◽

Laboratory Model ◽

Suction Pressure ◽

Pile Installation ◽

Nondimensional Parameter ◽

Pile Penetration ◽

The Relationship

A series of laboratory model tests on the suction pile installation in sand have been conducted to obtain the relationship between the applied suction pressure inside the pile and the resulting pile penetration. The relationships have been used to estimate the mobilized soil strength during the pile installation. This reduction in the soil strength due to the applied suction pressure is described as a function of a nondimensional parameter to characterize the variation and transition of the soil strength during the pile installation. The nondimensional parameter includes all pertinent pile and soil properties that are thought to affect the behavior of the suction pile during installation.Key words: suction pile, suction pressure, mobilized effective soil friction angle.

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