STRUCTURAL ANALYSIS OF WATER TANK FOR PROPOSED T …

STRUCTURAL ANALYSIS OF WATER TANK

FOR PROPOSED T-MOBILE EQUIPMENT

118’ WATER TANK

201 137TH STREET

OCEAN CITY, MD 21842

SITE NAME: OCEAN CITY NORTH

SITE ID: 7SAL048A

PROJECT NAME: 2021 ANCHOR & L600

Prepared For:

T-Mobile Northeast LLC

12050 Baltimore Avenue

Beltsville, MD 20705

Prepared by:

Advantage Engineers 7151 Columbia Gateway Drive, Suite A, Columbia, MD 21046 – (443) 367-0003

November 16, 2021 – AE Project # P-022143

TABLE OF CONTENTS

1.0 OBJECTIVE

Table 1 – Documentation

2.0 EXISTING & FINAL APPURTENANCES

Table 2 – Existing Discrete and Linear Appurtenances

Table 3 – Final T-Mobile Discrete and Linear Appurtenances

3.0 ANALYSIS STANDARDS

4.0 ANALYSIS METHOD

5.0 ANALYSIS ASSUMPTIONS

6.0 CONCLUSION

APPENDIX A CALCULATIONS

APPENDIX B ASCE 7 HAZARDS REPORT

November 16, 2021

Site Name: OCEAN CITY NORTH

Site ID: 7SAL048A

Project Name: 2021 ANCHOR & L600

1

1.0 OBJECTIVE

The objective of this report is to analyze the structural impact of the proposed T-Mobile installation on the

water tank supporting the antenna mounts at the above referenced address.

Advantage Engineers (AE) has reviewed the following documentation which was used as the basis for this

assessment:

Table 1 -- Documentation

DOCUMENT DESCRIPTION DATE

L700 Structural Analysis Maser, Project # 15951003A 10-20-15

Water Tank Mapping TEP, Job # 74714-62288 12-23-16

Mount Analysis Armor Tower, Project TMO 7SAL048A 06-08-21

T-Mobile RFDS Version 7 06-11-21

2.0 EXISTING & FINAL APPURTENANCES

Below is a list of the existing and final discrete and linear appurtenances located on the water tank that

were considered in this analysis:

Table 2 -- Existing Discrete and Linear Appurtenances

RAD CENTER APPURTENANCE1 MOUNT COAX

123’-0” Ocean City

(1) 5’ Dish

(1) 4’ Dish

(1) 2’ Dish

(1) 15’ Omni

(3) Tripods on

Top of Tank

(3) 7/8

(1) Microwave

Trunk

115’-0” Verizon

(6) X7C-FRO-840-V

(3) X7C-865-V

(3) AHCA

(3) B13 RRH4X30

(3) B25 RRH4X30-4R

(6) ETW200VS12UB

(12) Tripods w/

Horizontals on Tank

(12) 1-5/8

(3) 6x12 Hybrid

93-0” T-Mobile

(3) AIR21 B2A_B4P

(3) LNX-6515DS-A1M

(3) AIR32 B66A_B2A

(3) RRUS11 B12

(3) Twin Style 1B AWS TMA

(3) Sector Frames

on Legs

(12) 1-5/8

(3) 6x12 Hybrid

(1) 9x18 Hybrid

1- Italic represents equipment to be removed; Not considered in this analysis

Table 3 -- Final T-Mobile Discrete and Linear Appurtenances

RAD CENTER APPURTENANCE2 MOUNT COAX

93’-0”

(3) APXVAALL24_43-U-NA20

(3) AIR6449 B41

(3) VV-65A-R2B

(3) RADIO 4480 B71+B85A

(3) RADIO 4460 B25+B66

Use Existing

(3) 6x12 Hybrid

(1) 9x18 Hybrid +

(2) 6x12 Hybrid

2- Bold represents proposed equipment

November 16, 2021


Site ID: 7SAL048A


2

3.0 ANALYSIS STANDARDS

The following design standards were used for this assessment:

Building Code: IBC 2018

Risk Category: IV

Wind Speed: 140 mph

Exposure Category: D

Topographic Category: 1

The following ASD load combinations were used for this analysis:

• 1.0 D + 0.6 W

• 1.0 D + 0.7 E

4.0 ANALYSIS METHOD

The analysis approach used in this report is founded on the premise that if the supporting structure, which

will be used to support the proposed equipment, is structurally adequate per the aforementioned codes

and standards, then the proposed equipment may be placed at the desired location. Calculations for this

analysis are provided in the Appendices of this report.

5.0 ANALYSIS ASSUMPTIONS

• The structure was built in accordance with the manufacturer’s specifications

• The structure has been maintained in accordance with the manufacturer’s specification

• All structure components are in sufficient condition to carry their full design capacity

• All mount members were properly installed

• All appurtenances were properly installed

If any assumptions are not valid or have been made in error, AE should be notified to determine the effect

on the structural integrity of the structure.

6.0 CONCLUSIONS

AE has determined that an overall structural analysis of the water tank is not required per IEBC 2018

because the proposed vertical loading represents an increase of less than 5% in the tank’s design vertical

loads. In addition, seismic controls the tank’s global lateral system; therefore, the proposed lateral loading

represents an increase of less than 10% in the tank’s design lateral loads. Thus, the proposed T-Mobile

equipment can be installed as intended.

The conclusions and recommendations reached in this analysis are only applicable for the components of

the structure directly supporting the previously listed T-Mobile telecommunications equipment. Any

deviation of the support, load, placement, etc. will require AE to generate an additional structural analysis.

Further, no structural qualification is made or implied by this analysis for any existing structural members

not directly impacted by the T-Mobile installation. AE reserves the right to append or modify this report as

more information becomes available.

November 16, 2021


Site ID: 7SAL048A


3

If you have any questions, comments, or if you would like to discuss this in further detail, please feel free

to contact me at (443) 367-0003.

For Advantage Engineers:

Drew R. Mundt, PE

Maryland Professional Engineer

MD License #49864

Professional Certification. I hereby certify that these documents

were prepared or approved by me, and that I am a duly licensed

professional engineer under the laws of the State of Maryland,

License No. 49864, Expiration Date: 03-15-2022

11/16/2021

APPENDIX A

CALCULATIONS

Advantage Engineers, LLC Date: 07/13/20217151 Columbia Gateway Dr, Suite A Prepared By: DRM

Columbia, MD 21046 Job Number: P-022143

Applicable Codes: ASCE 7-16

Site Specific Inputs

Location:Structure Type: G: 0.85 Section 26.11.1Ultimate Wind Speed: 140 mph ASCE 7 Hazards Report Kd: 1.00 Section 26.6Risk Category: IV Section 1.5 Kd app: 0.85 Section 26.6Ground Elevation of Base: 6.48 ft Ke: 1.00 Section 26.9Exposure Category: D Section 26.7.3 Kzt: 1.00 Section 26.8.2Ground Snow Load: 20 psf ASCE 7 Hazards Report pf: 24.0 psf Section 7.3

Tank Wind Load: 194.6 kip Tank Dead Load: 6256.7 kip

Additional Wind Load Additional Dead LoadT-Mobile: 8.43 kip T-Mobile: 2.11 kipVerizon: 15.63 kip Verizon: 2.43 kipOcean City: 4.75 kip Ocean City: 0.45 kipCoax: 9.11 kip Coax: 2.58 kipTotal: 37.92 kip Total: 7.56 kip

Wind Load Increase: 19.49% Dead Load Increase: 0.12%

Water Tank Analysisfor T-Mobile

7SAL048A

2021 ANCHOR & L600

The proposed loading represents an increase of less than 5% in the water tank’s design vertical loads.

Seismic loading controls the water tank’s lateral system. Additionally, the proposed lateral seismic loading is less than a 10% increase in the water tank’s design lateral seismic loading.

Full analysis of the water tank is not required.

Water Tank Loading Increase Check Per 2018 IEBC, Sections 807.4 & 807.5

Multi-Leg

IBC 2018

Site Specific Outputs

Ocean City, MD

Water Tank Original Design Loading



Tank Top Height: 118 ft Elevation: 103.33 ft Cf: 0.5

Tank Bottom Height: 74 ft Kz: 1.44 Area: 2354.33 ft2

Tank Diameter: 62.5 ft qz: 72.29 psf Wind Load: 30.72 psf

Flat Wall Height: 14.5 ft Total Force: 72.34 kip

Tank Volume: 750000 gal

MemberTop

Height (ft)

Length

(ft)

Diameter/

Width (in)Shape

Elevation

(ft)Kz

qz

(psf)Cf Area (ft2) Force (plf) Quantity

Total Force

(kip)

Leg 88.75 88.75 36.00 Round 59.17 1.31 65.61 0.70 266.25 117.12 7 72.76

Riser 74.00 74.00 96.00 Round 49.33 1.27 63.57 0.61 592.00 264.77 1 19.59

Strut 43.33 28.00 8.00 Flat 43.33 1.24 62.15 2.00 18.67 70.44 7 13.81

Top Diagonal 88.75 53.50 1.75 Round 70.92 1.35 67.71 1.20 7.80 10.07 14 7.54

Bottom Diagonal 43.33 51.50 1.75 Round 26.16 1.13 56.93 1.20 7.51 8.47 14 6.11

Top Horizontal 74.00 31.25 1.00 Round 74.00 1.36 68.21 1.20 2.60 5.80 7 1.27

Bottom Horizontal 43.33 31.25 1.00 Round 43.33 1.24 62.15 1.20 2.60 5.28 7 1.16

122.23

Water Tank Member Loads

Water Tank Loads


7SAL048A

2021 ANCHOR & L600



Antenna Centerline (AGL): 93 ft

Velocity Pressure Coefficient Kz: 1.41 Section 26.10.1Velocity Pressure qz: 60.33 psf Section 26.10.2

Appurtenance Height (in) Width (in) Depth (in)Weight

(lbs)Cf EPAa (ft2) Force (lbs) Quantity Total Force (kip)

Total Weight

(kip)

APXVAALL24_43-U-NA20 96 24 8.5 123 1.35 21.60 1107.71 3 3.32 0.37

AIR 6449 B41 33.1 20.5 8.3 103 1.31 6.17 316.62 3 0.95 0.31

VV-65A-R1B 54.7 12.0 4.6 24.7 1.36 6.20 318.11 3 0.95 0.07

RADIO 4480 B71+B85A 21.8 15.7 7.5 84 1.31 3.11 159.25 3 0.48 0.25

RADIO 4460 B25+B66 19.6 15.7 12.1 109 1.30 2.79 142.92 3 0.43 0.33

Member Length (in) Width (in) TypeWeight

(lbs)Cf EPAa (ft2) Force (plf) Quantity Total Force (kip)

Total Weight

(kip)

Pipe Mount 72 2.375 Round 20.8 1.20 1.43 12.18 6 0.44 0.12

Pipe Mount 96 2.375 Round 27.8 1.20 1.90 12.18 3 0.29 0.08

Horizontal 120 2.375 Round 34.7 1.20 2.38 12.18 6 0.73 0.21

Support Pipe 144 4.5 Round 120.9 1.20 5.40 23.08 3 0.83 0.36

8.43 2.11


7SAL048A

2021 ANCHOR & L600

Member Weight & Wind Forces

Appurtenance Weight & Wind Forces

T-Mobile Loading







Total Weight

(kip)

X7C-FRO-840-V 98.5 18.8 9.1 58 1.37 17.63 937.93 6 5.63 0.35

X7C-865-V 96 12.5 7.1 40 1.42 11.86 630.86 3 1.89 0.12

AHCA 13.3 11.6 6.5 36.8 1.30 1.40 74.25 3 0.22 0.11

B25 RRH4X30-4R 21.4 12 7.2 51 1.31 2.34 124.60 3 0.37 0.15

B13 RRH 4X30 20.9 11.8 7.5 55.6 1.31 2.25 119.64 3 0.36 0.17

ETW200VS12UB 6.3 7.7 3.1 6.6 1.30 0.44 23.30 6 0.14 0.04



Total Weight

(kip)

Pipe Mount 96 2.375 Round 27.8 1.20 1.90 12.64 15 1.46 0.42

Kicker 72 3 Flat 29.4 1.97 2.95 26.16 24 3.63 0.71

Horizontal Angle 150 3 Flat 61.3 2.00 6.25 26.61 6 1.92 0.37

15.63 2.43


7SAL048A

2021 ANCHOR & L600


Verizon Loading








Total Weight

(kip)

5' Dish 60 60 12 80 1.30 32.50 1749.74 1 1.75 0.08

4' Dish 48 48 12 60 1.30 20.80 1119.83 1 1.12 0.06

2' Dish 24 24 6 40 1.30 5.20 279.96 1 0.28 0.04

15' Omni 180 3 3 10 1.20 7.50 403.79 1 0.40 0.01



Total Weight

(kip)

Pipe Mount 96 2.375 Round 27.8 1.20 1.90 12.79 3 0.29 0.08

Kicker 72 3 Flat 29.4 1.97 2.95 26.47 6 0.91 0.18

4.75 0.45


7SAL048A

2021 ANCHOR & L600


Ocean City Loading




Carrier # of Coax # of Rows Width (in) Length (ft)Elevation

(ft)kz

qz

(psf)Cf

Area

(ft2)Force (plf) Force (kip)

Dead Load

(kip)

T-Mobile 6 3 5.94 85.0 56.7 1.30 65.12 1.2 42.075 32.88 2.79 0.51

Verizon 15 3 5.94 107.0 71.3 1.35 67.78 1.2 52.965 34.22 3.66 1.61

Ocean City 4 2 3.96 115.0 76.7 1.37 68.64 1.2 37.95 23.10 2.66 0.46

Coax Loading


7SAL048A

2021 ANCHOR & L600



Soil Class: D Ie: 1.5 Table 1.5-2

SDS: 0.095 ASCE 7 Hazard Tool R: 3 Table 15.4-2

SD1: 0.058 ASCE 7 Hazard Tool Ct: 0.02 Table 12.8-2

TL: 8 s ASCE 7 Hazard Tool x: 0.75 Table 12.8-2

h: 74 ft Water Tank Dead Load supported at Riser Height T: 0.50 s Section 12.8.2.1

Cs: 0.0475 Section 12.8.1.1

Total Seismic Base Shear: 297.19 kip 0.7 E 208.03 kip ASCE 7 Load Combination 8

Total Wind Force: 232.49 kip 0.6 W 139.49 kip ASCE 7 Load Combination 5

The originally designed seismic forces are greater than the proposed lateral forces.

Seismic Loading

Total Lateral Forces Governing Lateral Load Check


7SAL048A

2021 ANCHOR & L600

APPENDIX B

ASCE 7 HAZARDS REPORT

ASCE 7 Hazards ReportAddress:No Address at This Location

Standard: ASCE/SEI 7-16

Risk Category: IV

Soil Class: D - Default (see Section 11.4.3)

Elevation: 6.48 ft (NAVD 88)

Latitude:Longitude:

38.441979

-75.055137

Wind

Results:

Wind Speed: 140 Vmph

10-year MRI 78 Vmph

25-year MRI 87 Vmph

50-year MRI 95 Vmph

100-year MRI 102 Vmph

Data Source: ASCE/SEI 7-16, Fig. 26.5-1D and Figs. CC.2-1–CC.2-4, and Section 26.5.2

Date Accessed: Mon Jul 12 2021

Value provided is 3-second gust wind speeds at 33 ft above ground for Exposure C Category, based on linear interpolation between contours. Wind speeds are interpolated in accordance with the 7-16 Standard. Wind speeds correspond to approximately a 1.6% probability of exceedance in 50 years (annual exceedance probability = 0.00033, MRI = 3,000 years).

Site is in a hurricane-prone region as defined in ASCE/SEI 7-16 Section 26.2. Glazed openings shall be protected against wind-borne debris as specified in Section 26.12.3.

Page 1 of 3https://asce7hazardtool.online/ Mon Jul 12 2021

https://asce7hazardtool.online/

SS : 0.089

S1 : 0.036

Fa : 1.6

Fv : 2.4

SMS : 0.143

SM1 : 0.086

SDS : 0.095

SD1 : 0.058

TL : 8

PGA : 0.043

PGA M : 0.068

FPGA : 1.6

Ie : 1.5

Cv : 0.7

Design Response Spectrum

S (g) vs T(s)a

MCE Response SpectrumR

S (g) vs T(s)a

Design Vertical Response Spectrum

S (g) vs T(s)a

MCE Vertical Response SpectrumR

S (g) vs T(s)a

Seismic

Site Soil Class:

Results:

Seismic Design Category

D - Default (see Section 11.4.3)

A

Data Accessed:

Date Source:

Mon Jul 12 2021USGS Seismic Design Maps based on ASCE/SEI 7-16 and ASCE/SEI 7-16 Table 1.5-2. Additional data for site-specific ground motion procedures in accordance with ASCE/SEI 7-16 Ch. 21 are available from USGS.



Snow

Results:

Ground Snow Load, p : 20 lb/ftg

2

Elevation: 6.5 ft

Data Source: ASCE/SEI 7-16, Table 7.2-8

Date Accessed: Mon Jul 12 2021

Values provided are ground snow loads. In areas designated "case study required," extreme local variations in ground snow loads preclude mapping at this scale. Site-specific case studies are required to establish ground snow loads at elevations not covered.

The ASCE 7 Hazard Tool is provided for your convenience, for informational purposes only, and is provided “as is” and without warranties of any kind. The location data included herein has been obtained from information developed, produced, and maintained by third party providers; or has been extrapolated from maps incorporated in the ASCE 7 standard. While ASCE has made every effort to use data obtained from reliable sources or methodologies, ASCE does not make any representations or warranties as to the accuracy, completeness, reliability, currency, or quality of any data provided herein. Any third-party links provided by this Tool should not be construed as an endorsement, affiliation, relationship, or sponsorship of such third-party content by or from ASCE.

ASCE does not intend, nor should anyone interpret, the results provided by this Tool to replace the sound judgment of a competent professional, having knowledge and experience in the appropriate field(s) of practice, nor to substitute for the standard of care required of such professionals in interpreting and applying the contents of this Tool or the ASCE 7 standard.

In using this Tool, you expressly assume all risks associated with your use. Under no circumstances shall ASCE or its officers, directors, employees, members, affiliates, or agents be liable to you or any other person for any direct, indirect, special, incidental, or consequential damages arising from or related to your use of, or reliance on, the Tool or any information obtained therein. To the fullest extent permitted by law, you agree to release and hold harmless ASCE from any and all liability of any nature arising out of or resulting from any use of data provided by the ASCE 7 Hazard Tool.



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