FINAL SI REPORT1 of 6
LONGITUDE
ONE TWENTY"
ENGINEERING & LIESIGN
Pile Review for Structural Compliance
Date: November 29"', 2021
Project Name: Foundation Stabilization/Lift — Edmonds Project Number: S201123-1XR
Project Location: 16706 74th PI W, Edmonds, WA 98026
Client's Name: Andi Hohn, Project Coordinator — R&R Foundation Specialist, LLC
I
To Whom It May Concern:
The purpose of this letter is to confirm pile installation and capacity compliance with the structural re-
quirements specified in the L120 Structural Calculation Package and Structural Site Plan dated May 6th,
2021.
On June 30'h, 2021, twelve (12) helical piles and eight (8) helical tiebacks were installed by R&R Foundation
Specialists (R&R) to stabilize areas of the single-family residence located at 16706 74th PI W, Edmonds, WA
98026. To the knowledge of L120, these piles were installed by R.&R. certified installers in accordance with
the cited structural package, ESR-3750. Please refer to the attached drive log and photographs provided by
R&R_
Please note that the referenced Structural Calculation Package indicated thirteen (13) helical piles. Helical
Pile #1 was removed with approval of L120 in order to prevent damage to the septic system. Please refer
to the attached drive log and photographs provided by R&R.
The helical piles were installed with maximum pile spacing of 6'-0" on -center, the typical minimum required
vertical capacity as determined by L120 is shown in the table below. These demand requirements are as
determined and specified in L120's structural calculation package cited above.
PILE SPACING & LOAD REQUIREMENTS TABLE
MAX O.C. SPACING, ft MIN VERTICAL CAPACITY, kips
I PROOF TESTING LOAD, kips
PILE #
PILE TYPE
200% MIN VERTICAL CAPACITY
LOCATION
BTWN PILES
END OFFSET
ALLOWABLE LOADING
(MIN.ULTIMATE CAPACITY)
1-6
HELICAL I N/A
N/A
9.0 k/PILE
18.0 k/PILE
POSTS
7.13
HELICAL I 6'-0"
PER PLAN
13.0 k/PILE
26.0 k/PILE
TYP EXTERIOR
TIEBACK
SPACING & LOAD REQUIREMENTS
TABLE
MAX O.C. SPACING, ft
I MIN VERTICAL CAPACITY, kips PROOF TESTING LOAD, kips
TIEBACK #
TIEBACK
200% MIN VERTICAL CAPACITY
LOCATION
TYPE
BTWN PILES
END OFFSET
ALLOWABLE LOADING
(MIN ULTIMATE. CAPACITY)
TYP
HELICAL
6'-0"
PER PLAN
11.0 k/PILE
22.0 k/PILE
TYP EXTERIOR
2 of 6
Pile capacities for the helical piles have been calculated using a Digga MM-10K drive head with a torque
correlation factor, Kt, of 9 as prescribed in ESR-3750. A chart showing the resulting capacities is attached
to this letter. Per the attached document, an Ideal Foundation Systems 2-7/8" diameter helical pile installed
to a minimum pressure of 1,000 psi results in a maximum allowable capacity of 15.7 kips including a safety
factor of 2"
The results are summarized below:
Helical Piles #2-#6:
Maximum Demand (allowable): 9.0 kips/pile
Available Capacity (allowable): 16.4 kips/pile
Helical Piles #7-#13:
Maximum Demand (allowable): 13.0 kips/pile
Available Capacity (allowable): 16.4 kips/pile
Helical Tiebacks #1-#8:
Maximum Demand (allowable): 11.0 kips/pile
Available Capacity (allowable): 15.7 kips/pile
By inspection, the pile capacities of the installed piles exceed the maximum loading demand as determined
by L120's analysis. Therefore, the installed piles comply with the structural design/demand.
Please contact us if you have any questions.
Sincerely,
ZT Yang, P.E.
L120 Engineering & Design (L120)
"-,:va"ii1. i:?`i
Mans R. Thurfjell, P.E.
L120 Engineering Design (L120)
i,wih,,irf;lf i; il•'i f')iit'i:?31?;r. •,'t>i: .$,?'7�
•
vz�
�m
mbqq'wmm
mmmmmm
mmmmmm
mmmmmm
mmmmmm
mmmmmm
,mom■
■■gym
NAMMIN
_MMMMOMMMM i= -
mmmmmmmmmm
mmmmmmmmmm
Iimmmmmmmmr
lmmrmmmmmmm
AIM
M
L401
125)
636 3313
OIMEngineering.com
1 of 6
Project Name: Foundation Stabilization/Lift — Edmonds Project Number: S201123-1XR
Project Location: 16706 74t1i Pl W, Edmonds, W4 98026
Client's Name: Andi Holm, Project Coordinator — R&R Foundation Specialist, LLC
(2) ROWS -OF PILES
6`-0" OC MAX W! VERT C10X15.3
LOWER PILES 2'-0" FROM TIGRADE
UPPER PILES.6' 0" FROM'T/GRADE
-->N
Ilk
CENTER PILES ON _
EXISTING POSTS
R = Exisling Post
it 1
( 3" HQIiCal Pilo
3 518 -3 318.
=Helical Tieback,� i �
'(2) PILES
3141/4 -3/ _- 1 1 3/6
3t8
ILOI)ATE PILE WITHIN 1' .13
1 FROM WINDOW POSTS
LOCATE PILE
WITHIN V-0" 2 2
3 I 51 s .. 71 s o nlN FROM Cf)RNEFt:
1 12_ 4 N 8 02
i 0 , CENTER PILE ON
WALL SEGMENT
0 0 1/4 0 -5/8 id8
fi3'
5 of 6
MAX
Project Name: Foundation Stabilization/Lift - Edmonds Project Number: S201123-1XR
Project Location: 16706 74tf' PI ZIT, Edmonds, WA 98026
Client's Name: Andi Holm, Project Coordinator - R&R Foundation Specialist, LLC
Subject: 2 - 7/8" 0 Helical Pile - Compression Torque Chart - Digga AIA•1-10K
- Ideal Foundation§ stemsb7/8"6 Hetic, i Pile 0.203-inchwalt thickness Soil Ca act >er ESR-3750
DIGGA IOK Drive Head �~Torque,T Torque Correlation Factor, K, Uftfmate Axial Compressfye Copocity,; Allowable Axial Cornpr essive
Pressure (psi) (ft fibs) Compresslon (ftJ P. = K,"T (kips) i Copacity, P, =0.5"p" (kips)
Soo
1,740
9
15.7 t 7.8
600
2,088
9
18.8 i 9.4
760
2,436
9
2L9 r 11.0
600
2,784
9
25.1 12.5
900
3,132
9
29.2 14.1
100D
3,480-
9
31.3 15.7
110D
3,823
9
120D
4,176�
9
37.6 18.8
130D
4,524
9
40.7 t 20.4
1400
4,872
9
43.8 21.9
15o0
5,220
9
47.0 23.5
1.600
5,568
9
5D.1 25.1
1700
5,916
9
53.2 j 26.6
180D
6,264
9
56.4 28.2
1900
6,612
9
59.5 29.8
2000
6,960
9
62.6 i 31.3
2100
7,308
9
65.8 32.9
2200
7,656
9
68.9 434.5
230D
8,000
9
72.0 36.0
i.) DIGGA 10K olive Head differential pressure display to torque output has been pt:lled from the attached conversion charts provided by 0166A.
h.) Per Table 5A of ESR-3750, the maximum i installation torque rating of a 2-7/9 "0 helical pile (0.203-Inch wall thickness) is 8,306 ft'Ibs, Per Ideal Manufacturing, Inc., the
maximum installation torque rating of a 2-7/8"0 helical pile {0.203-inch wall thickness) Is 8,000 ft'lbs. Final installation torque shall not exceed the lesser of these limiting values.
W.) Piles shall reach a torque that correlates with an allowable capacity that meets or exceeds the maximum allowable toad demand as listed in the structural package, but shall not
exceed the maximum allowable capacity for.any part of the pile assembly.
iv.) Refer to ESR-3750and ideolMonufocturing, Inc. documents for additional information and requirements.
v.) Dehnitions_per UR-3750:
T = Final installation torque in ft"ibs; the la sttorque reading taken during pile installation, using, for example, the torque reading Instruments connected
to the installation equipment.
Kt Torque correlation factor per ESR-3750
Pv= Ultimate axial compressive capacity (In kips) of helical pile
P. = Allowable axial compressive capacity (In kips) of helical pile
vi.) For torque readings between those listed, use the fdlloWing equation to determine the allowable capacity: P. = (T'K,)/2
0.) 1 kip = 1,000 Ibs
D_igga - Speed & Torque Chart
Model Code: MM - 10K
GF: 262
rpm vs Ipm
20
15
10
CD
0
0 20 40 60 80
Flow rate (Ipm)
Max. Flow I m 70
Max. Soeed (rr)m)l 16
Output Torque
Differential
Pressure
Display
Nm
Bar
2,360
34
2,632
41
3,303
48
3,775
55
4,247
62
4,71.9
69
5,191
76
5,663
83
6,135
90
6,607
7,079
97
103
7,651
110
8,023
117
8,495
124
8,967
131
9,438
138
9,910
145
10,382
152
10,854
159
T1,326
166
11,798
172
12,270
f79
12,742
186
13,214
193
13,686
200
44,158
20.7
rpm vs gpm
_ !
E 15
i CL I
ro 10 i ...
t � }
3 °3 5
V)
[ 0
I
0 5 10 15 20
Flow rate (gpm) !
i
Max. Flow m 18
Max. Speed (rpm) 16
Differential
Pressure
Display
Output Torque
PSI
ibf-ft
500
1,740
600
21088
700
2,437
800
2,785
900
3,133
1,000
3,481
1,100
3,829
1,200
4,477
1,300
4,525
1,400
4,873
5,221
1,500
1,600
5,569
1,700
5,917
1,800
6,265
1,900
6,613
2,000
6,961
2,100
7,310
2,200
7,658
2,300
8,006
2,400
8,354
2,500
8,702
2,600
9050
2,700
9,398
Z800
9,746
2,900
10,094
3,000
10,442
" IMPORTANT: This chart is based on theoretical values and is provided as a guide only. Digga accepts no
responsibility complying with any installation requiring certain torques being reached. You will need to consult an
engineer.