July/August 2023 - 18

Concrete pile: example moment development and provided reinforcement
Highway traffic loads per Canadian Highway Bridge Code
were added as surcharge with lateral active earth pressures
acting on the pile wall stem. Load and material resistance
factors, again per the code, were applied to the nongeotechnical
loads as appropriate to combine with the FLAC ULS loads.
The RFEM load increment analysis results were combined
by superposition to yield the shears and moments in each type
of pile with due account for load sharing. By way of a check, the
total section forces of a concrete-composite-concrete triplet,
divided by the wall length of the triplet were compared with
the FLAC results and found to be in good agreement.
In one example of a moment diagram for a concrete pile
obtained using the above approach, the effect of anchor
installation and stressing is clearly visible (Step 26b) as is the
increase in anchor load due to seismic effects (Step 27). FLAC
Step 28b modelled the effects of destressing the upslope
anchors, which of course would initiate some slide
movement and commensurate increases in soil pressures on
the pile wall. Meticulous readers will note the extra
longitudinal reinforcement provided in the upper portion of
the pile. This compensates for bars that were cut during the
coring for tie-back anchor installation.
Observational Method During Construction - The 2D
soil-structure interaction modelling in FLAC to estimate
loading and response of the stabilization structures to
construction and potential future conditions is complex and
several assumptions were made that are based on estimated
movement rates and soil parameters. While the analyses
were considered representative and were the basis of
engineering decisions and design, application of the
observational method during construction was considered a
key component to the project execution. Based on monitoring
results, the design could be adapted to suit changing
conditions as construction proceeded. The monitoring and
instrumentation program included:
* Electronic vibrating wire load cells on selected soil
anchors and the tie-back anchors.
* Slope inclinometer casings cast into selected composite
piles of the pile wall and distributed on the slope above the
highway.
* Ground surface displacement measurements by the
contractor during construction using survey monuments,
together with ground-based, terrestrial laser scanning
and change detection analysis by BGC Engineering.
18 * DEEP FOUNDATIONS * JULY/AUG 2023

July/August 2023

Table of Contents for the Digital Edition of July/August 2023

TOC
July/August 2023 - Intro
July/August 2023 - 1
July/August 2023 - 2
July/August 2023 - TOC
July/August 2023 - 4
July/August 2023 - 5
July/August 2023 - 6
July/August 2023 - 7
July/August 2023 - 8
July/August 2023 - 9
July/August 2023 - 10
July/August 2023 - 11
July/August 2023 - 12
July/August 2023 - 13
July/August 2023 - 14
July/August 2023 - 15
July/August 2023 - 16
July/August 2023 - 17
July/August 2023 - 18
July/August 2023 - 19
July/August 2023 - 20
July/August 2023 - 21
July/August 2023 - 22
July/August 2023 - 23
July/August 2023 - 24
July/August 2023 - 25
July/August 2023 - 26
July/August 2023 - 27
July/August 2023 - 28
July/August 2023 - 29
July/August 2023 - 30
July/August 2023 - 31
July/August 2023 - 32
July/August 2023 - 33
July/August 2023 - 34
July/August 2023 - 35
July/August 2023 - 36
July/August 2023 - 37
July/August 2023 - 38
July/August 2023 - 39
July/August 2023 - 40
July/August 2023 - 41
July/August 2023 - 42
July/August 2023 - 43
July/August 2023 - 44
July/August 2023 - 45
July/August 2023 - 46
July/August 2023 - 47
July/August 2023 - 48
July/August 2023 - 49
July/August 2023 - 50
July/August 2023 - 51
July/August 2023 - 52
July/August 2023 - 53
July/August 2023 - 54
July/August 2023 - 55
July/August 2023 - 56
July/August 2023 - 57
July/August 2023 - 58
July/August 2023 - 59
July/August 2023 - 60
July/August 2023 - 61
July/August 2023 - 62
July/August 2023 - 63
July/August 2023 - 64
July/August 2023 - 65
July/August 2023 - 66
July/August 2023 - 67
July/August 2023 - 68
July/August 2023 - 69
July/August 2023 - 70
July/August 2023 - 71
July/August 2023 - 72
July/August 2023 - 73
July/August 2023 - 74
July/August 2023 - 75
July/August 2023 - 76
July/August 2023 - 77
July/August 2023 - 78
July/August 2023 - 79
July/August 2023 - 80
July/August 2023 - 81
July/August 2023 - 82
July/August 2023 - 83
July/August 2023 - 84
July/August 2023 - 85
July/August 2023 - 86
July/August 2023 - 87
July/August 2023 - 88
July/August 2023 - 89
July/August 2023 - 90
July/August 2023 - 91
July/August 2023 - 92
July/August 2023 - 93
July/August 2023 - 94
July/August 2023 - 95
July/August 2023 - 96
July/August 2023 - 97
July/August 2023 - 98
July/August 2023 - 99
July/August 2023 - 100
July/August 2023 - 101
July/August 2023 - 102
July/August 2023 - 103
July/August 2023 - 104
July/August 2023 - 105
July/August 2023 - 106
July/August 2023 - 107
July/August 2023 - 108
July/August 2023 - 109
July/August 2023 - 110
July/August 2023 - 111
July/August 2023 - 112
July/August 2023 - 113
July/August 2023 - 114
July/August 2023 - 115
July/August 2023 - 116
July/August 2023 - 117
July/August 2023 - 118
July/August 2023 - 119
July/August 2023 - 120
July/August 2023 - 121
July/August 2023 - 122
July/August 2023 - 123
July/August 2023 - 124
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/september-october-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2024
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/september-october-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/Jan-feb-2021_nxtbook
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2023
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/september-october-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2022
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/sept-oct-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-aug-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2021
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/november-december-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/September-October-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/may-june-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/march-april-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/january-february-2020
https://www.nxtbook.com/dfi/DEEP-FOUNDATIONS/july-august-2020
https://www.nxtbookmedia.com