Investigation of Geometric and Smear Parameters in the Design of Prefabricated Vertical Drains in Manila Bay
- DOI
- 10.2991/978-94-6463-258-3_42How to use a DOI?
- Keywords
- PVD; Smear; Consolidation; Drain Spacing; Drain Configuration
- Abstract
Prefabricated Vertical Drains (PVDs) are geosynthetic drains that are used to shorten the horizontal drainage path and allow water to flow laterally to the nearest drain. Because of remolding during installation, a zone of smear around the drain is formed, reducing the coefficient of horizontal permeability, and thus increasing time needed for consolidation. A sensitivity analysis was conducted to study the effects of varying PVD drain spacing, configuration, and smear properties in a multi-staged embankment using a soil profile in Manila Bay. A higher benefit in terms of increased maximum settlements is achieved when decreasing larger drain spacings as opposed to decreasing smaller drain spacings. However, the opposite is true for reduced consolidation times, wherein a higher benefit is achieved when decreasing smaller drain spacings as opposed to decreasing larger drain spacings. Meanwhile, a triangular configuration yields higher maximum settlements and lower consolidation times compared to that of a square configuration, with an average reduction in consolidation times of 32%. Additionally, a higher benefit in terms of increased settlement and reduced consolidation times is observed across all cases for smaller ratios of
$$d_{s} /d$$ and$$k_{h} /k_{s}$$ corresponding to the ratio of the diameter of the smear zone and the drain, and the ratio of the horizontal permeability of undisturbed soil and the smear zone, respectively. Changing the drain spacing has the largest effect in consolidation times, with an average reduction of 77.69%. This is then followed by the smear properties$$k_{h} /k_{s}$$ and$$d_{s} /d$$ , with an average reduction of 58.03% and 49.84% respectively. The study reveals that an ideal drain design in terms of higher settlements and reduced consolidation times has a spacing of between 0.75 m and 1.0 m, triangular configuration, and installed with drain installation procedures that yield low$$d_{s} /d$$ and$$k_{h} /k_{s}$$ ratios.- Copyright
- © 2023 The Author(s)
- Open Access
- Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.
Cite this article
TY - CONF AU - Ian-Will D. Ibañez AU - Giancarlo P. Ventura PY - 2023 DA - 2023/11/08 TI - Investigation of Geometric and Smear Parameters in the Design of Prefabricated Vertical Drains in Manila Bay BT - Proceedings of the Rocscience International Conference (RIC 2023) PB - Atlantis Press SP - 425 EP - 431 SN - 2589-4943 UR - https://doi.org/10.2991/978-94-6463-258-3_42 DO - 10.2991/978-94-6463-258-3_42 ID - Ibañez2023 ER -