RSPile Analysis of Two Osterberg Cell Load Tests on Post-Grouted and Conventionally Installed Caissons in Vaughan, Ontario

DOI

10.2991/978-94-6463-258-3_54How to use a DOI?

Keywords

Site investigations; foundation engineering; deep foundations; Osterberg Cell; load test; pile modelling

Abstract

Three towers (35–57 storeys) are proposed in Vaughan, Ontario. The preferred foundation approach is bored concrete piles (caissons) bearing in soil at about 46 m depth, with Osterberg Cell (O-Cell) load testing to maximize design capacity. Several conventional O-Cell load tests have been designed and analyzed by Grounded Engineering in the vicinity. An alternative novel approach was recommended at this site: a two-caisson test investigating the feasibility of caissons with post-grouted pile tips compared with conventional tremie concrete caissons. Using load cell pressure as well as telltale, LVDT, and strain gauge data from both fully instrumented caissons, t-z and Q-z curves were input into RSPile to numerically model both conventional and post-grouted load tests to verify soil parameters. Once the model was verified, the loading was switched from bidirectional at the base to top-down loading to estimate the Equivalent Top Load (ETL) for caissons of different diameters using RSPile. Settle3 was used to model the change in effective vertical stress from the test condition to the final building condition, including excavation unload, dewatering, and 3D effects, over the full pile depth profile. The resulting stress reduction was built into the RSPile production pile ETL model. A table of capacities for various production caisson diameters, for both conventional and post-grouted options, was produced using RSPile. A significant cost savings is anticipated for either option when compared to conventional parameters, due to the innovative test design and numerical modelling.

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.

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TY  - CONF
AU  - Michael Diez de Aux
AU  - Jason Crowder
AU  - John Westland
PY  - 2023
DA  - 2023/11/08
TI  - RSPile Analysis of Two Osterberg Cell Load Tests on Post-Grouted and Conventionally Installed Caissons in Vaughan, Ontario
BT  - Proceedings of the Rocscience International Conference  (RIC 2023)
PB  - Atlantis Press
SP  - 575
EP  - 592
SN  - 2589-4943
UR  - https://doi.org/10.2991/978-94-6463-258-3_54
DO  - 10.2991/978-94-6463-258-3_54
ID  - deAux2023
ER  -