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Marine structures placed in the shallower seabed can experience pore water drainages with more complexity than those in onshore environments, particularly in coarse-grained soils where drainage is neither purely “drained” nor “undrained,” but Partially Drained (PD). However, current laboratory approaches for characterizing soil behavior are limited to modeling drainage conditions as fully drained or undrained. This paper presents results from a series of confined monotonic saturated simple shear tests under various drainage conditions on reconstituted medium dense to dense Monterey sand specimens to fill this knowledge gap. Although others have performed limited PD element-level tests under triaxial conditions, no documentation exists for tests using a simple monotonic shear configuration. To achieve PD, a special filter was fabricated and connected between the bottom of the specimen and the backpressure controller. The hydraulic filter comprises a series of needle valves to provide various hydraulic impedances. All simple shear tests in this paper were backpressure-saturated. Two different degrees of PD were considered and compared with fully drained and undrained conditions. Results show that the excess pore water pressure generation and measured volumetric changes in the PD tests are bounded between those measured from fully drained and undrained, proving the PD filter provided the hydraulic resistance to achieve PD condition.
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Stabilizing Effect of High Pore Fluid Pressure on Fault Growth During Drained Deformation
Key Points High pore fluid pressure stabilizes fault propagation in porous sandstone deformed under drained conditions Slow faulting was associated with pervasive microcracking and diffuse shear bands only in samples deformed sufficiently slow Pervasive subcritical cracking enables slow faulting at high pore fluid pressure under drained conditions at the sample scale
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- PAR ID:
- 10465072
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Solid Earth
- Volume:
- 128
- Issue:
- 8
- ISSN:
- 2169-9313
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1029/2023JB026536
