B08_Att_16_Reports_CLIN_1-17.pdf

REHABILITATE LITTLE ROUND TOP VISITOR

USE AREA

GETTYSBURG NATIONAL MILITARY PARK

GETT PMIS NO. 250272

PROJECT FORMS

FOR CLIN 1-17

NATIONAL PARK SERVICE

DENVER SERVICE CENTER

SEPTEMBER 13, 2021

CONSTRUCTION DOCUMENTS

GETT - 250272 TOC-1

TABLE OF CONTENTS

FOR CLIN 1-38

PROJECT FORMS

Drainage Calculations (FOR CLIN 1-17) Statement of Structural Tests and Special Inspections (FOR CLIN 1-17) Structural Calculations (FOR CLIN 1-17) Geotechnical Investigation Report (FOR CLIN 1-17)

NATIONAL PARK SERVICE

REHABILITATE LITTLE ROUND TOP

VISITOR USE AREA

NPS CONTRACT NO. P15PC00039

TASK ORDER NUMBER 140P2020F0133

D R A I N A G E C A L C U L A T I O N S

WSP USA

412 MOUNT KEMBLE AVENUE

MORRISTOWN, NJ 07960

TEL.: +1 973 407-1000

WSP.COM

WSP PROJECT NO.: LF2042267.007

DATE: JUNE 29, 2021

REHABILITATE LITTLE ROUND TOP VISITOR USE AREA

Project No. LF2042267.007

National Park Service

WSP

Page iii

TABLE OF

CONTENTS

1 PROJECT BACKGROUND

1.1 Introduction

2 DRAINAGE CALCULATIONS DESIGN

2.1 Runoff Calculations

2.2 Swale Design CAlculations

2.3 Storm Drain Design Calculations

2.4 Curb Opening Design Calculations

2.5 Riprap Apron Design Calculations

APPENDICES

A SWALE DESIGN CALCULATIONS

B STORM DRAIN DESIGN CALCULATIONS

C CURB OPENING DESIGN CALCULATIONS

D RIPRAP APRONV DESIGN CALCULATIONS

National Park Service

WSP

1 PROJECT BACKGROUND

1.1 INTRODUCTION

The National Park Service (NPS) is proposing site improvements at the Little Round Top Visitor Use area at Gettysburg National Military Park. The project site encompasses approximately 16 acres and is located in the Borough of Gettysburg in Adams County, Pennsylvania. This project is to rehabilitate the cultural and natural landscapes of the area while improving accessibility, pedestrian safety and pedestrian circulation, protecting natural landscape, and improving traffic control and parking. A primary goal of the project is the elimination of safety concerns and natural resource damage within the project area.

The project proposes new roadwork, car and bus parking, new trails and pathways, as well as, improvements to existing pathways and pedestrian gathering areas. Other site features proposed include walls to minimize areas of grading. Site grading, erosion control and drainage improvements are part of the project.

Little Round Top is considered the key point in the American Civil War. On July 2nd 1863, the 20th Maine Volunteer Infantry Regiment of the Union Army’s defensive line fought the most famous engagement on Little Round Top, culminating in a dramatic downhill bayonet charge that is one of the most well-known actions at Gettysburg and in the American Civil War.

National Park Service

WSP

2 DRAINAGE CALCULATIONS DESIGN

2.1 RUNOFF CALCULATIONS

Runoff calculations to calculation flow rates in support of the drainage system design were performed using the Rational Method, Q = ciA, in accordance with Chapter 5 of the Pennsylvania Department of Environmental Protection Erosion and Sediment Pollution Control Manual (The Manual), dated March 2012. Where “Q” is flow rate in cubic feet per second, “c” is the weighted runoff coefficient, “i” is rainfall intensity in inches per hour, and “A” is the drainage area in acres. The weighted runoff coefficient is calculated using 0.95, 0.6 and 0.3 for impervious, compacted earth and wooded covered areas, respectively. In accordance with The Manual, the 10-year design storm was utilized, and rainfall intensities determined.

2.2 SWALE DESIGN CALCULATIONS

Swale design calculations are presented in Appendix A. Calculations are performed in accordance with The Manual utilizing Worksheet #11. Swales are designed with erosion control blanket (ECB) to prevent erosion and sized for the 10-year design storm.

2.3 STORM DRAIN DESIGN CALCULATIONS

Storm drain design calculations are presented in Appendix B. Calculations are performed using Manning’s equation to determine pipe capacity. Consistent with The Manual, the storm drains are sized for the 10-year design storm.

2.4 CURB OPENING DESIGN CALCULATIONS

Curb opening design calculations are presented in Appendix C. The calculations are designed considering depth of flow and gutter spread along the road. The curbs openings are design for the 10-year design storm and rainfall intensity for these calculations are from NOAA Atlas 14.

2.5 RIPRAP APRON DESIGN CALCULATIONS

Riprap aprons for each of the outfalls are designed in accordance with The Manual and presented in Appendix D. The have been calculated based on the 10-year peak design flow at each outfall. Stone class size selected is based on The Manual’s riprap gradation.

APPENDIX

A SWALE DESIGN

CALCULATIONS

PROJECT NAME: Rehabilitate Little Round Top Visitor Use Area PMIS NO: 318022

LOCATION: Gettysburg National Military Park, Adams County, Pennsylvania

PREPARED BY: KTC DATE: 5/25/2021

CHECKED BY: RM DATE: 5/29/2021

1 2

P P

10 YR 10 YR

1.11 1.15

2.75 2.75

2.78 2.66

2.54 4.80

=(1.49/n)(R H 2/3

)(S 0.5

)(A)

ECB ECB

0.028 0.028

10 10

5.84 6.42

V CHECK OK OK

2.25 2.25

From Table 6.2

1.82 1.90

=62.4 x d x S τ CHECK OK OK

1 2

1.5 2

1.5 2

5.5 10

0.3 0.29

1.9 3.16

3.33 6.90

12:1 CHECK OK OK

n/a n/a

0.435 0.7482

Pw (WETTED PERIMETER) (FT) 2.08 3.30

0.21 0.23

0.097 0.105

0.021 0.020

0.015 0.014

0.027 0.025

Y Y

0.131 0.140

=0.075 V d

0.075 0.073

= 0.25 x d

0.075 0.073

NOTES:

1. Use 1.6 for Temporary Channels; 2.25 for Temporary Channels in Special Protection (HQ or EV) Watersheds; 2.75 for

Permanent Channels. For Rational Method, enter “N/A” and attach E&S Worksheets 9 and 10. For TR-55 enter “N/A” and attach appropriate Worksheets.

2. Adjust “n” value for changes in channel liner and flow depth. For vegetated channels, provide data for manufactured linings without vegetation and with vegetation in separate columns.

3. Slopes may not be averaged.

4. Minimum Freeboard is 0.5 ft. or ¼ Total Channel Depth, whichever is greater

5. Permissible velocity lining design method is not acceptable for channels with a bed slope of 10% or greater. Shear stress lining design method is required for channels with a bed slope of 10% or greater. Shear stress lining design method may be used for any channel bed slope.

FREEBOARD BASED ON STABLE FLOW (FT)

MINIMUM REQUIRED FREEBOARD

(FT)

DESIGN METHOD FOR PROTECTIVE LINING

PERMISSIBLE VELOCITY (V) OR SHEAR STRESS (S)

S S

Sc (CRITICAL SLOPE) (FT/FT)

.7Sc (FT/FT)

1.3Sc (FT/FT)

STABLE FLOW? (Y/N)

FREEBOARD BASED ON UNSTABLE FLOW (FT)

S (BED SLOPE)

(FT/FT)

τd (CALC. SHEAR STRESS AT FLOW DEPTH d) (LB/FT

CHANNEL BOTTOM WIDTH (FT)

CHANNEL SIDE SLOPES (H:V)

D (TOTAL DEPTH) (FT)

CHANNEL TOP WIDTH @ D (FT)

d (CALCULATED FLOW DEPTH) (FT)

CHANNEL TOP WIDTH @ FLOW DEPTH d (FT)

BOTTOM WIDTH: FLOW DEPTH RATIO (12:1 MAX)

d50 STONE SIZE (IN)

A (CROSS-SECTIONAL AREA) (SQ. FT.)

R (HYDRAULIC RADIUS)

STANDARD E&S WORKSHEET #11

Channel Design Data τd (MAX ALLOWABLE SHEAR STRESS) (LB/FT

CHANNEL OR CHANNEL SECTION

TEMPORARY OR PERMANENT? (T OR P)

DESIGN STORM (2, 5, OR 10 YR)

ACRES (AC)

MULTIPLIER (1.6, 2.25, or 2.75)

Qr (REQUIRED CAPACITY) (CFS)

Q (CALCULATED AT FLOW DEPTH d) (CFS)

PROTECTIVE LINING

n (MANNING’S COEFFICIENT)

Va (ALLOWABLE VELOCITY) (FPS)

V (CALCULATED AT FLOW DEPTH d) (FPS)

363-2134-008 / March 31, 2012 / Page 130

For trapezoidal channels with up to 10’ bottom width, Table 6.3 may be used to determine the “n” value. When rock riprap is proposed, use Figure 6.2 to determine the "n" value.

The seed mixture used in vegetative channels should be suitable for the anticipated flow conditions based on the channel location and type of soil(s) encountered. The Department recommends the use of Tables 11.3, 11.4, and 11.5 taken from the Penn State Publication, Erosion Control and Conservation Plantings on Noncropland, for selection of species to be used.

TABLE 6.2

Maximum Permissible Shear Stresses for Various Channel Liners

Lining Category Lining Type lb/ft2

Unlined1- Easily Eroded Soils2 Silts, Fine -Medium Sands 0.03

Coarse Sands 0.04

Very Coarse Sands 0.05

Fine Gravel 0.10

Unlined1- Erosion Resistant Soils3 Clay Loam 0.25

Silty Clay Loam 0.18

Sandy Clay Loam 0.10

Loam 0.07

Silt Loam 0.12

Sandy Loam 0.02

Gravely, Stony, Channery Loam 0.05

Stony or Channery Silt Loam 0.07

Manufactured Liners4 Jute 0.45

Straw with Net 1.45

Coir - Double Net 2.25

Coconut Fiber -Double Net 2.25

Curled Wood Mat 1.55

Curled Wood-Double Net 1.75

Curled Wood - Hi Velocity 2.00

Synthetic Mat 2.00

Non Reinforced Vegetation Retardance C assumed5 1.00

Riprap6 R-3 1.00

R-4 2.00

R-5 3.00

R-6 4.00

R-7 5.00

R-8 8.00

1. Not permitted in HQ or EV watersheds

2. Soils having an erodibility “K” factor greater than 0.37.

3. Soils having an erodibility “K” factor less than or equal to 0.37

4. Manufacturer’s recommended maximum shear stresses may be used if supporting documentation is provided showing the higher shear stresses are justified by independent testing results over a time period of at least 20 minutes.

5. For description of Vegetative Retardance C, see USDOT, Federal Highway Administration Publication HEC15.

6. Permissible shear stresses based on rock at 165 lb/cu. ft. Adjust shear stresses for other rock weights used. See Table 6.8.

Adapted from USDOT, FHA HEC-15, 1988

B STORM DRAIN

DESIGN

Project: By: TC Checked: RM Location: Date: 5/25/2021 Date: 5/28/2021 PMIS No.: Sheet:

Runoff Coefficient Calculations

Total Area C = 0.95 C = 0.6 C = 0.3 Acres

sq. ft. ac sq. ft. ac sq. ft. ac 2404 0.055 14402 0.331 0.386 0.39

909 0.021 0.021 0.95 1641 0.038 0.038 0.95 3123 0.072 3154 0.072 0.144 0.62 2533 0.058 0.058 0.95

11028 0.253 632 0.01 5230 0.120 0.388 0.74 3431 0.079 712 0.02 2584 0.059 0.154 0.66 4844 0.111 4096 0.094 0.205 0.65

316 0.007 0.007 0.95 3105 0.071 6257 0.144 0.215 0.52

209 0.005 0.005 0.95 2948 0.07 761 0.02 9691 0.222 0.308 0.46 4100 0.09 0.094 0.95 2865 0.07 0.066 0.95

I 12 I 13

I 9

I 11

CW =

Σ(AxC)/ADesignation

I 5

I 2

RUNOFF COEFFICIENT CALCULATIONS

Rehabilitate Little Round Top Visitor Use Area Gettysburg National Military Park, Adams County, PA 318022

Imp. Grass

I 7 I 8

I 3

I 1

I 10

I 6

Drainage Area Gravel

I 14

I 4

PROJECT: DESIGN STORM = 10 YR. CAL. BY: DATE:

PMIS NO.: TYPE OF PIPES: MANNING'S N= CHK. BY: DATE:

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I 1 I 1 I 2 18 0.386 0.393 5 6.96 1.06 0.152 5.00 6.96 1.06 3.06% 15 12.25 3.00 6.19 0.05 628.00 622.00 621.45 4.8

I 2 I 2 I 3 11 0.021 0.950 5 6.96 0.14 0.171 5.00 6.96 1.19 10.00% 15 22.17 2.60 9.75 0.02 626.83 621.20 620.10 4.4

I 3 I 3 H 1 21 0.038 0.950 5 6.96 0.25 0.207 5.00 6.96 1.44 0.75% 15 6.07 4.88 4.01 0.09 626.81 619.85 619.69 5.7

H 1 619.69

I 4 I 4 I 5 11 0.144 0.623 5 6.96 0.63 0.090 5.00 6.96 0.63 0.91% 15 6.68 3.00 3.38 0.05 638.06 632.40 632.30 4.4

I 5 I 5 H 2 17 0.058 0.950 5 6.96 0.38 0.145 5.00 6.96 1.01 0.59% 15 5.38 4.35 3.29 0.09 637.84 632.10 632.00 4.5

H 2 632.00

I 10 I 10 I 11 11 0.215 0.516 5 6.96 0.77 0.111 7.00 6.96 0.77 9.09% 15 21.14 1.95 7.75 0.02 640.62 635.00 634.00 4.4

I 6 I 6 I 7 35 0.388 0.736 5 6.96 1.99 0.285 7.00 6.96 1.99 1.89% 15 9.63 4.65 6.12 0.10 645.66 641.16 640.50 3.3

I 7 I 7 I 8 35 0.154 0.663 5 6.96 0.71 0.388 5.00 6.96 2.70 1.29% 15 7.95 6.00 5.57 0.10 645.02 640.25 639.80 3.5

I 8 I 8 I 9 31 0.205 0.652 5 6.96 0.93 0.522 5.00 6.96 3.63 12.10% 15 24.38 3.75 13.71 0.04 644.30 639.55 635.80 3.5

I 9 I 9 I 11 28 0.007 0.950 5 6.96 0.05 0.528 5.00 6.96 3.68 1.79% 15 9.37 6.60 6.56 0.07 643.00 634.00 633.50 7.8

I 11 I 11 H 3 16 0.005 0.950 5 6.96 0.03 0.644 6.00 6.96 4.48 3.13% 15 12.39 6.30 8.68 0.03 640.62 633.00 632.50 6.4

H 3 633.50

I 12 I 12 I 13 88 0.308 0.460 5 6.96 0.98 0.142 5.00 6.96 0.98 4.49% 15 14.85 2.60 6.54 0.22 613.00 608.50 604.55 3.3

I 13 I 13 I 14 90 0.094 0.950 5 6.96 0.62 0.231 5.00 6.96 1.61 2.83% 15 11.80 3.68 6.54 0.23 611.15 604.30 601.75 5.6

I 14 I 14 H 4 36 0.066 0.950 5 6.96 0.43 0.293 6.00 6.96 2.04 4.17% 15 14.31 3.75 8.05 0.07 608.50 601.50 600.00 5.8

H 4 H 4 600.00

RCP318022

Rehabilitate Little Round Top Visitor Use Area

PIPE SECTION INLET CALCULATIONS ELEVATIONS & COVERSTORM DRAIN CALCULATIONS

S T O R M D R A I N C A L C U L A T I O N S

0.012

KTC

RM

5/25/2021 5/28/2021

C CURB OPENING

PROJECT:

DATE: April 30, 2021

PREPARED BY: RDM

ROADWAY

WIDTH

MAX. CENTER TO

CENTER SPACING OF

CURB OPENINGS

CURB

OPENING

(LENGTH)

DRAINAGE

AREA

RAINFALL

INTENSITY

FLOW

RATE, Q

VELOCITY

AT

OPENING

ROADWAY

SLOPE

GUTTER

SPREAD

DEPTH OF

FLOW

CAPTURE

CAPACITY

CAPTURE

EFFICIENCY

VELOCITY NOTES

FT FT FT AC IN/HR CFS FPS FT/FT FT FT CFS % FPS

15 75 3 0.0129 5.07 0.065 0.731 0.129 1.493 0.030 0.046 71% 0.627

USE EROSION CONTROL

BLANKET FOR EROSION

CONTROL

15 75 3 0.0129 5.07 0.065 0.587 0.04 1.859 0.037 0.064 98% 0.503

USE EROSION CONTROL

BLANKET FOR EROSION

CONTROL

CONCLUSIONS:

FLOW RATE AND DISCHARGE LOW ENOUGH AT CURB OPENINGS TO USE EROSION CONTROL BLANKET.

NOTES

1 RAINFALL INTENSITY FOR 10 YR, 10 MINUTE STORM

2 RATIONAL METHOD USED FOR FLOW RATE CALCULATION

3 FLOW RATE ASSUMES 100% IMPERVIOUSNESS OF ROADWAY AREA

4 RAINFALL INTENSITY FROM NOAA ATLAS 14

5 DRAINAGE AREA TAKES INTO ACCOUNT CROWNED ROADWAY.

6 GUTTER FLOW CALCULATIONS PERFORMED FOR MAXIMUM AND MINIMUM ROADWAY GRADES.

GUTTER FLOW CALCULATIONS

DISCHARGE ONTO OPEN SPACE

CALCULATIONS

Rehabilitate Little Round Top Visitor Use Area, Gettysburg National Military Park

CURB CUT AND GUTTER FLOW CALCULATIONS

4/30/2021 PF Map: Contiguous US https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_map_cont.html 1/2 www.nws.noaa.gov

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Data description

Data type: Precipitation intensity Units: English Time series type: Partial duration

Select location

1) Manually:

a) By location (decimal degrees, use "-" for S and W): Latitude: Longitude: Submit

b) By station (list of PA stations): EISENHOWER NATL HIST S (36-2537)

c) By address

2) Use map (if ESRI interactive map is not loading, try adding the host: https://js.arcgis.com/ to the firewall, or contact us at hdsc.questions@noaa.gov):

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b) Click on station icon Show stations on map

Location information:

Name: Gettysburg, Pennsylvania, USA*

Station name: GETTYSBURG Site ID: 36-2537 Latitude: 39.8333° Longitude: -77.2333° Elevation: 541 ft

* Source: ESRI Maps ** Source: USGS

PF tabular PF graphical Supplementary information

PDS-based precipitation frequency estimates with 90% confidence intervals (in inches/hour)1

Duration Average recurrence interval (years)

1 2 5 10 25 50 100 200 500 1000

5-min 4.08 (3.68‑4.52)

4.86 (4.38‑5.40)

5.80 (5.22‑6.43)

6.49 (5.84‑7.19)

7.43 (6.64‑8.20)

8.16 (7.27‑9.00)

8.90 (7.90‑9.82)

9.70 (8.56‑10.7)

10.8 (9.48‑11.9)

11.8 (10.2‑12.9)

10-min 3.21 (2.90‑3.56)

3.84 (3.46‑4.26)

4.55 (4.10‑5.06)

5.07 (4.57‑5.62)

5.77 (5.16‑6.38)

6.31 (5.62‑6.97)

6.87 (6.09‑7.57)

7.43 (6.55‑8.18)

8.21 (7.18‑9.04)

8.83 (7.66‑9.70)

15-min 2.65 (2.39‑2.94)

3.17 (2.86‑3.52)

3.77 (3.40‑4.19)

4.22 (3.80‑4.68)

4.80 (4.30‑5.30)

5.25 (4.68‑5.80)

5.73 (5.08‑6.32)

6.21 (5.48‑6.84)

6.86 (6.00‑7.55)

7.37 (6.40‑8.10)

30-min 1.78 (1.61‑1.97)

2.15 (1.94‑2.39)

2.63 (2.37‑2.92)

2.98 (2.69‑3.31)

3.47 (3.10‑3.83)

3.84 (3.42‑4.24)

4.24 (3.77‑4.68)

4.66 (4.11‑5.13)

5.24 (4.58‑5.77)

5.72 (4.97‑6.29)

60-min 1.10 (0.990‑1.22)

1.33 (1.20‑1.48)

1.66 (1.50‑1.85)

1.92 (1.73‑2.13)

2.27 (2.03‑2.51)

2.57 (2.29‑2.83)

2.88 (2.55‑3.17)

3.21 (2.83‑3.53)

3.69 (3.22‑4.06)

4.09 (3.55‑4.49)

2-hr 0.634 (0.571‑0.710)

0.770 (0.694‑0.858)

0.970 (0.872‑1.08)

1.13 (1.01‑1.26)

1.37 (1.22‑1.52)

1.58 (1.40‑1.74)

1.81 (1.59‑2.00)

2.06 (1.80‑2.28)

2.45 (2.12‑2.71)

2.79 (2.39‑3.08)

3-hr 0.465 (0.416‑0.526)

0.562 (0.503‑0.636)

0.705 (0.631‑0.797)

0.822 (0.733‑0.926)

0.994 (0.881‑1.12)

1.14 (1.01‑1.28)

1.31 (1.15‑1.47)

1.50 (1.30‑1.67)

1.78 (1.53‑1.99)

2.03 (1.73‑2.27)

6-hr 0.292 (0.261‑0.333)

0.352 (0.315‑0.401)

0.439 (0.391‑0.501)

0.513 (0.455‑0.582)

0.623 (0.549‑0.706)

0.721 (0.630‑0.814)

0.832 (0.721‑0.938)

0.958 (0.822‑1.08)

1.15 (0.977‑1.30)

1.32 (1.11‑1.49)

12-hr 0.179 0.215 0.269 0.316 0.388 0.453 0.528 0.614 0.750 0.872

NOAA ATLAS 14 POINT PRECIPITATION FREQUENCY ESTIMATES: PA

POINT PRECIPITATION FREQUENCY (PF) ESTIMATES

WITH 90% CONFIDENCE INTERVALS AND SUPPLEMENTARY INFORMATION

NOAA Atlas 14, Volume 2, Version 3

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6km

4mi

Map Terrain http://www.nws.noaa.gov/ http://www.noaa.gov/ http://www.nws.noaa.gov/ https://www.weather.gov/owp/hdsc https://www.weather.gov/owp/oh_sitemap http://www.nws.noaa.gov/organization.html https://www.weather.gov/owp/hdsc https://www.weather.gov/owp/hdsc_current_projects https://www.weather.gov/owp/hdsc_FAQ https://www.weather.gov/owp/hdsc_glossary https://hdsc.nws.noaa.gov/hdsc/pfds/index.html https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_gis.html https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_maps.html https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_series.html https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_temporal.html https://www.weather.gov/owp/hdsc_currentpf https://www.weather.gov/owp/hdsc_pmp https://www.weather.gov/owp/hdsc_publications https://www.weather.gov/owp/hdsc_aep https://www.weather.gov/owp/hdsc_record_precip https://www.weather.gov/owp/hdsc_contact https://www.usa.gov/ https://hdsc.nws.noaa.gov/pub/hdsc/data/xlslists/pa.xls mailto:HDSC.questions@noaa.gov https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?st=pa&sta=36-2537&data=intensity&units=english&series=pds

4/30/2021 PF Map: Contiguous US https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_map_cont.html 2/2

(0.159‑0.206) (0.191‑0.248) (0.237‑0.309) (0.277‑0.362) (0.338‑0.441) (0.391‑0.514) (0.452‑0.596) (0.520‑0.691) (0.625‑0.843) (0.718‑0.977)

24-hr 0.105 (0.096‑0.117)

0.126 (0.115‑0.141)

0.157 (0.143‑0.175)

0.185 (0.168‑0.205)

0.229 (0.206‑0.252)

0.269 (0.240‑0.295)

0.317 (0.280‑0.345)

0.373 (0.326‑0.405)

0.464 (0.400‑0.501)

0.548 (0.466‑0.590)

2-day 0.061 (0.055‑0.068)

0.073 (0.066‑0.082)

0.091 (0.082‑0.102)

0.106 (0.096‑0.119)

0.131 (0.118‑0.146)

0.154 (0.137‑0.171)

0.181 (0.160‑0.201)

0.213 (0.186‑0.235)

0.264 (0.228‑0.291)

0.312 (0.265‑0.343)

3-day 0.043 (0.039‑0.048)

0.052 (0.047‑0.058)

0.064 (0.058‑0.071)

0.075 (0.068‑0.083)

0.092 (0.083‑0.102)

0.108 (0.096‑0.119)

0.126 (0.112‑0.139)

0.148 (0.130‑0.163)

0.183 (0.158‑0.201)

0.215 (0.184‑0.236)

4-day 0.034 (0.031‑0.038)

0.041 (0.038‑0.046)

0.051 (0.046‑0.056)

0.059 (0.054‑0.066)

0.073 (0.066‑0.080)

0.085 (0.076‑0.093)

0.099 (0.088‑0.109)

0.116 (0.102‑0.127)

0.143 (0.124‑0.155)

0.167 (0.143‑0.182)

7-day 0.023 (0.021‑0.025)

0.027 (0.025‑0.030)

0.033 (0.031‑0.037)

0.039 (0.035‑0.043)

0.047 (0.043‑0.052)

0.055 (0.049‑0.060)

0.063 (0.057‑0.070)

0.074 (0.065‑0.081)

0.090 (0.079‑0.098)

0.105 (0.090‑0.114)

10-day 0.018 (0.017‑0.020)

0.022 (0.020‑0.024)

0.026 (0.024‑0.029)

0.030 (0.028‑0.033)

0.036 (0.033‑0.040)

0.042 (0.038‑0.046)

0.048 (0.043‑0.052)

0.055 (0.049‑0.060)

0.066 (0.058‑0.072)

0.076 (0.066‑0.083)

20-day 0.012 (0.012‑0.013)

0.015 (0.014‑0.016)

0.017 (0.016‑0.018)

0.019 (0.018‑0.021)

0.023 (0.021‑0.024)

0.026 (0.024‑0.027)

0.029 (0.026‑0.031)

0.032 (0.029‑0.034)

0.037 (0.034‑0.040)

0.042 (0.038‑0.045)

30-day 0.010 (0.010‑0.011)

0.012 (0.011‑0.013)

0.014 (0.013‑0.015)

0.015 (0.015‑0.016)

0.018 (0.017‑0.019)

0.020 (0.019‑0.021)

0.022 (0.020‑0.023)

0.024 (0.023‑0.026)

0.028 (0.026‑0.029)

0.031 (0.028‑0.033)

45-day 0.009 (0.008‑0.009)

0.010 (0.009‑0.011)

0.011 (0.011‑0.012)

0.013 (0.012‑0.013)

0.014 (0.013‑0.015)

0.016 (0.015‑0.016)

0.017 (0.016‑0.018)

0.019 (0.017‑0.020)

0.021 (0.019‑0.022)

0.023 (0.021‑0.024)

60-day 0.008 (0.007‑0.008)

0.009 (0.008‑0.009)

0.010 (0.010‑0.011)

0.011 (0.010‑0.012)

0.012 (0.012‑0.013)

0.014 (0.013‑0.014)

0.015 (0.014‑0.015)

0.016 (0.015‑0.017)

0.018 (0.017‑0.019)

0.019 (0.018‑0.020)

1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).

Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.

Please refer to NOAA Atlas 14 document for more information.

Estimates from the table in CSV format: Precipitation frequency estimates Submit

Main Link Categories:

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D RIPRAP APRON

STANDARD E&S WORKSHEET # 20

Riprap Apron Outlet Protection

PROJECT NAME: Rehabilitate Little Round Top Visitor Use Area LOCATION: Gettysburg National Military Park, Adams County Pennsylvania

PREPARED BY: K T C DATE: 05/25/2021

CHECKED BY: R M DATE: 05/28/2021

NO.

PIPE

DIA.

Do (in.)

TAIL

WATER

COND.

(Max or

Min)

MAN.

“n”

FOR

PIPE

PIPE

SLOPE

(FT/FT)

Q

(CFS)

V*

(FPS)

RIPRAP

SIZE

Rt (in)

Al (ft)

Aiw (ft)

Atw (ft)

H1 15 Max 0.012 .008 6.07 4.01 R-3 12 10 3.75 14 H2 15 Max 0.012 .006 5.38 3.29 R-3 12 10 3.75 14

H3 15 Max 0.012 .031 12.39 7.88 R-4 12 16 3.75 20

H4 15 Max 0.012 .042 14.31 8.05 R-4 15 16 3.75 20

*:The anticipated velocity (V) should not exceed the maximum permissible shown in Table 6.6 for the proposed riprap protection. Adjust for less than full pipe flow. Use Manning’s equation to calculate velocity for pipe slopes > 0.05 ft/ft.

363-2134-008 / March 31, 2012 / Page 239

FIGURE 9.3

Riprap Apron Design, Minimum Tailwater Condition

Adapted from USDA - NRCS

Not to be used for Box Culverts

NOTE: Do not extrapolate

USKC675920

Line

USKC675920

Line

USKC675920

Text Box H1

USKC675920

Text Box H3

USKC675920

Text Box H4

USKC675920

Line

USKC675920

Line

USKC675920

Line

USKC675920

Text Box H2

USKC675920

Line

USKC675920

Line

USKC675920

Line

USKC675920

Line

USKC675920

Line

USKC675920

Line

USKC675920

Line

363-2134-008 / March 31, 2012 / Page 135

TABLE 6.6

Riprap Gradation, Filter Blanket Requirements, Maximum Velocities

Percent Passing (Square Openings)

Class, Size

NO.

R-8

R-7

R-6

R-5

R-4

R-3 Rock Size (Inches)

42 100

30 100

24 15-50 100

18 15-50 100

15 0-15

12 0-15 15-50 100

9 15-50

6 0-15 15-50 100

4 0-15

3 0-15 15-50

2 0-15

Nominal Placement Thickness (inches)

Filter

Stone1

AASHTO #1

AASHTO #3

AASHTO #3

AASHTO #57

Vmax (ft/sec)

17.0

14.5

13.0

11.5

9.0

6.5

Adapted from PennDOT Pub. 408, Section 703.2(c), Table C

1 This is a general standard. Soil conditions at each site should be analyzed to determine actual filter size. A suitable woven or non-woven geotextile underlayment, used according to the manufacturer's recommendations, may be substituted for the filter stone for gradients < 10%.

TABLE 6.7

Comparison of Various Gradations of Coarse Aggregates

Total Percent Passing

AASHTO

NUMBER

6 ½ 4" 3 ½" 2 ½ 2" 1 ½ " 1" 3/4 " 1/2" 3/8" #4 #8 #16 #30 #100

1 100 90-100 25-60 0-15 0-5

3 100 90-100 35-70 0-15 0-5

5 100 90-100 20-55 0-10 0-5

57 100 90-100 25-60 0-10 0-5

67 100 90-100 20-55 0-10 0-5

7 100 90-100 40-70 0-15 0-5

8 100 85-100 10-30 0-10 0-5

10 100 75-100 10-30

PennDOT Publication 408, Section 703.2(c), Table C

Tables 6.6 and 6.7 should be placed on the plan drawings of all sites where riprap channel linings are proposed.

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 1 of 7

Statement of Structural Tests and Special Inspections

National Park Service - Denver Service Center

Park: Gettysburg National Military Park

PMIS: 250272

Project Name: Rehabilitate Little Round Top Visitor Use Area

Structural Engineering Firm: WSP USA Solutions, Inc

This Statement of Structural Tests and Special Inspections is being submitted as required by

Chapter 17 of the 2015 International Building Code (IBC-15). It includes the following:

1. Qualification requirements for Inspectors and Testing Technicians

2. Listing of Required Structural Tests and Special Inspections

The Construction Contractor’s Quality Control Supervisor will provide copies of all special inspection reports and associated documentation to the Contracting Officer. The Construction

Contractor will be required to correct all deficiencies discovered in the Special Inspection and

Structural Testing program.

Prepared by:

Adam Walker, P.E.____________________________________

(Type or print name)

Signature Date PE or SE Stamp

Seismic and Wind Requirements

6/28/21

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 2 of 7

Qualification Requirements for Inspectors and Testing Technicians

PE/SE Structural Engineer – licensed PE or SE specializing in the design of buildings and structures

PE/GE Geotechnical Engineer – licensed PE specializing in soil mechanics and foundations

EIT Engineer-In-Training – graduate engineer who has passed the Fundamentals of engineering examination

American Concrete Institute (ACI) Certification

ACI-CCSI Concrete Construction Special Inspector

ACI-LTT Concrete Laboratory Testing Technician Level 1 or 2

ACI-STT Concrete Strength Testing Technician

ACI-FTT Concrete Field Testing Technician – Grade I

American Society of Non-Destructive Testing (ASNT) Certification

Non-Destructive Testing Technician – Level II or III

American Welding Society (AWS) Certification

AWS-CWI Certified Welding Inspector

Exterior Design Institute (EDI) Certification

EDI-EIFS Certified EIFS inspector

International Code Council (ICC) Certification

ICC-PCSI Prestressed Concrete Special Inspector

ICC-RCSI Reinforced Concrete Special Inspector

ICC-SSI Soils Special Inspector

ICC-SFSI Spray-applied Fireproofing Special Inspector

ICC-SMSI Structural Masonry Special Inspector

ICC-SSBSI Structural Steel and Bolting Special Inspector

ICC-SWSI Structural Welding Special Inspector

National Institute for Certification in Engineering Technologies (NICET) Certification

NICET-CT Concrete Technician – Levels I, II, III and IV

NICET-GET Geotechnical Engineering Technician - Levels I, II, III and IV

NICET-ST Soils Technician - Levels I, II, III and IV

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 3 of 7

Listing of Required Structural Tests and Special Inspections

R eq u ir ed

Structural Test or Special Inspection Required

Qualifications

C o n ti n u o u s

P er io d ic

F re q u en cy o f

P er io d ic T es t o r

In sp ec ti o n

Steel Construction (ref: IBC-15 Section 1705.2, AISC 360-10 Chapter N, AISC 341-

10 Chapter J)

Prior to Welding (AISC 360-10 Table N5.4-1)

1. Welding procedure specifications (WPSs) available AWS-CWI X

2. Manufacturer certifications for welding consumables available

AWS-CWI X

3. Material identification (type/grade) AWS-CWI X At least one visit to shop during guardrail fabrication

4. Welder identification system AWS-CWI X As above

5. Fit-up of groove welds (including joint geometry) AWS-CWI As above

a. Joint preparation AWS-CWI X As above

b. Dimensions (alignment, root opening, root face, bevel) AWS-CWI X As above

c. Cleanliness (condition of steel surfaces) AWS-CWI X As above

d. Tacking (tack weld quality and location) AWS-CWI X As above

e. Backing type and fit (if applicable) AWS-CWI X As above

6. Configuration and finish of access holes AWS-CWI X As above

7. Fit-up of fillet welds AWS-CWI

a. Dimensions (alignment, gaps at root) AWS-CWI X As above

b. Cleanliness (condition of steel surfaces) AWS-CWI X As above

c. Tacking (tack weld quality and location) AWS-CWI X As above

8. Check welding equipment AWS-CWI X As above

During Welding (AISC 360-10 Table N5.4-2)

1. Use of qualified welders AWS-CWI X At least one visit to shop during guardrail fabrication

2. Control and handling of welding consumables AWS-CWI

a. Packaging AWS-CWI X As above

b. Exposure control AWS-CWI X As above

3. No welding over cracked tack welds AWS-CWI X As above

4. Environmental conditions

a. Wind speed within limits

b. Precipitation and temperature

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 4 of 7 u ir

Qualifications

C o n ti n u o u s

P er io q u en cy o f

P er io d ic T es t o r

In sp ec ti

5. WPS followed AWS-CWI

a. Settings on welding equipment AWS-CWI X At least one visit to shop during guardrail fabrication

b. Travel speed AWS-CWI X As above

c. Selected welding materials AWS-CWI X As above

d. Shielding gas type/flow rate AWS-CWI X As above

e. Preheat applied AWS-CWI X As above

f. Interpass temperature maintained (min. /max.) AWS-CWI X As above

g. Proper position (F, V, H, OH) AWS-CWI X As above

h. Intermix of filler metals avoided unless approved (ref:

AISC 341-10)

AWS-CWI X As above

6. Welding techniques AWS-CWI

a. Interpass and final cleaning AWS-CWI X As above

b. Each pass within profile limitations AWS-CWI X As above

c. Each pass meets quality requirements AWS-CWI X As above

After Welding (AISC 360-10 Table N5.4-3)

1. Welds cleaned AWS-CWI X At least one visit to shop during guardrail fabrication

2. Size, length and location of welds AWS-CWI X As above

3. Welds meet visual acceptance criteria AWS-CWI

a. Crack prohibition AWS-CWI X As above

b. Weld/base-metal fusion AWS-CWI X As above

c. Crater cross section AWS-CWI X As above

d. Weld profiles AWS-CWI X As above

e. Weld size AWS-CWI X As above

f. Undercut AWS-CWI X As above

g. Porosity AWS-CWI X As above

4. Arc strikes AWS-CWI X As above

5. k-area AWS-CWI X As above

6. Backing removed and weld tabs removed (if required) AWS-CWI X As above

7. Repair activities AWS-CWI X As above

8. Document acceptance or rejection of welded joint or member

AWS-CWI X As above

9. Placement of reinforcing or contouring fillet welds (if required) (ref: AISC 341-10)

AWS-CWI X As above

10. Backing removed, weld tabs removed and finished, and fillet welds added (if required) (ref: AISC 341-10)

AWS-CWI X As above

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 5 of 7 u ir

Qualifications

C o n ti n u o u s

P er io q u en cy o f

P er io d ic T es t o r

In sp ec ti

Nondestructive Testing (AISC 360-10 Section N5.5)

1. Risk Category II Structures - Perform Ultrasonic Testing on 10% of CJP groove welds in butt, T- and corner joints subject to transversely applied tension loading, in materials 5/16 in. thick or greater.

N/A X

2. Risk Category III or IV Structures - Perform Ultrasonic

Testing on all CJP groove welds subject to transversely applied tension loading in butt, T- and corner joints, in materials 5/16 in. thick or greater.

N/A X

3. Access Holes – Perform Magnetic Particle Testing or

Liquid Penetrant Testing when the flange thickness exceeds 2 in. for rolled shapes, or when the web thickness exceeds 2 in. for built-up shapes.

N/A X

4. Welded Joints Subject to Fatigue N/A X

Nondestructive Testing (AISC 341-10 Section J6.2)

1. k-area AWS-CWI X At least one visit to shop during guardrail fabrication

2. CJP Groove weld AWS-CWI X As above

3. Lamellar tearing N/A

4. Beam cope and access hole AWS-CWI X As above

5. Reduced beam section repair AWS-CWI X As above

6. Weld tab removal AWS-CWI X As above

Prior to Bolting (AISC 360-10 Table N5.6-1)

These inspections are not required for snug-tight joints

1. Manufacturer’s certifications available for fastener materials

AWS-CWI X

2. Fasteners marked in accordance with ASTM requirements AWS-CWI X At least one visit to site during guardrail erection

3. Proper fasteners selected for the joint detail (grade, type, bolt length if threads are to be excluded from shear plane)

AWS-CWI X As above

4. Proper fasteners selected for the joint detail (grade, type, bolt length if threads are to be excluded from shear plane)

AWS-CWI X As above

5. Connecting elements, including the appropriate faying surface condition and hole preparation, if specified, meet applicable requirements

AWS-CWI X As above

6. Pre-installation verification testing by installation personnel observed and documented for fastener

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 6 of 7 u ir

Qualifications

C o n ti n u o u s

P er io q u en cy o f

P er io d ic T es t o r

In sp ec ti assemblies and methods used

7. Proper storage provided for bolts, nuts, washers and other fastener components

During Bolting (AISC 360-10 Table N5.6-2)

These inspections are not required for snug-tight joints.

These inspections are not required for pretensioned joints and slip-critical joints, when the installer is using the turn-of-nut method with matchmarking techniques, the direct-tension-indicator method, or the twist-off-type tension control bolt method.

1. Fastener assemblies, of suitable condition, placed in all holes and washers (if required) are positioned as required

AWS-CWI X At least one visit to site during guardrail erection

2. Joint brought to the snug-tight condition prior to the pretensioning operation

AWS-CWI X As above

3. Fastener component not turned by the wrench prevented from rotating

AWS-CWI X As above

4. Fasteners are pretensioned in accordance with the RCSC

Specification, progressing systematically from the most rigid point toward the free edges

After Bolting (AISC 360-10 Table N5.6-3)

Document acceptance or rejection of bolted connections AWS-CWI X

Other Inspection Tasks (AISC 360-10 Section N5.7)

1. Verify compliance of fabricated steel with the details shown on the approved shop drawings.

AWS-CWI X At least one visit to site during guardrail erection

2. Verify compliance of the erected steel frame with the details shown on the approved erection drawings, including braces, stiffeners, member locations and joint details.

AWS-CWI X As above

3. Anchor rods and other embedments support structural steel

AWS-CWI As above

a. Verify the diameter, grade, type and length of the anchor rod or embedded item.

AWS-CWI X As above

b. Verify the extent or depth of embedment into the concrete.

AWS-CWI X As above

4. RBS requirements, if applicable (ref: AISC 341-10) N/A

a. Contour and finish N/A

b. Dimensional tolerances N/A

5. Protected zone—no holes and unapproved attachments N/A

PARK/PMIS Statement of Structural Tests and Special Inspections, 1-11-17 Page 7 of 7 u ir

Qualifications

C o n ti n u o u s

P er io q u en cy o f

P er io d ic T es t o r

In sp ec ti made by fabricator or erector, as applicable (ref: AISC

341-10)

6. H-piles - Protected zone—no holes and unapproved attachments made by the responsible contractor, as applicable (ref: AISC 341-10)

N/A

GETT Little Round Top

Structural Calculations

WSP

44th NY and Cannon Retaining Walls

WSP USA Solutions, Inc

Project

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

RETAINING WALL ANALYSIS

In accordance with International Building Code 2018

Tedds calculation version 2.9.08

Analysis summary

Description Unit Capacity Applied F o S Result Sliding stability plf 1974 1046 1.887 PASS

Overturning stability lb_ft/ft 4882 2788 1.751 PASS

Bearing pressure psf 3500 1820 1.923 PASS

Design summary

Description Unit Provided Required Utilisation Result Stem p0 rear face - Flexural reinforcement in2/ft 0.307 0.075 0.24 PASS

Stem p0 - Shear resistance lb/ft 11028 1057 0.10 PASS

Base top face - Flexural reinforcement in2/ft 0.196 0.389 1.98 FAIL

Base bottom face - Flexural reinforcement in2/ft 0.196 0.389 1.98 FAIL

Base - Shear resistance lb/ft 17930 1389 0.08 PASS

Transverse stem reinforcement in2/ft 0.393 0.288 0.73 PASS

Transverse base reinforcement in2/ft 0.393 0.389 0.99 PASS

Retaining wall details

Stem type; Cantilever

Stem height; hstem = 5.1 ft

Stem thickness; tstem = 12 in

Angle to rear face of stem; α = 90 deg

Stem density; γstem = 150 pcf

Toe length; ltoe = 0.5 ft

Heel length; lheel = 1.5 ft

Base thickness; tbase = 18 in

Base density; γbase = 150 pcf

Height of retained soil; hret = 3.5 ft

Angle of soil surface; β = 0 deg

Depth of cover; dcover = 1.5 ft

Depth of excavation; dexc = 0.667 ft

Retained soil properties

Moist density; γmr = 135 pcf

Saturated density; γsr = 145 pcf

Effective angle of internal resistance; φr = 32 deg

Effective wall friction angle; δr = 16 deg

Base soil properties

Soil type; Medium dense well graded sand

Soil density; γb = 120 pcf

Cohesion; cb = 0 psf

Effective angle of internal resistance; φb = 32 deg

Effective wall friction angle; δb = 16 deg

Effective base friction angle; δbb = 20 deg

Allowable bearing pressure; Pbearing = 3500 psf

OK due to low demand

OK due to low demand

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Loading details

Live surcharge load; SurchargeL = 60 psf

Horizontal line load at 8.5 ft; PL1 = 50 plf P1

1820 psf 0 psf

60 psf 18 psf

288 psf

3'

6" 1' 1' 6"

' 6

.2

General arrangement

Calculate retaining wall geometry

Base length; lbase = ltoe + tstem + lheel = 3 ft

Moist soil height; hmoist = hsoil = 5 ft

Length of surcharge load; lsur = lheel = 1.5 ft

- Distance to vertical component; xsur_v = lbase - lheel / 2 = 2.25 ft

Effective height of wall; heff = hbase + dcover + hret = 6.5 ft

- Distance to horizontal component; xsur_h = heff / 2 = 3.25 ft

Area of wall stem; Astem = hstem × tstem = 5.1 ft2

- Distance to vertical component; xstem = ltoe + tstem / 2 = 1 ft

Area of wall base; Abase = lbase × tbase = 4.5 ft2

- Distance to vertical component; xbase = lbase / 2 = 1.5 ft

Area of moist soil; Amoist = hmoist × lheel = 7.5 ft2

- Distance to vertical component; xmoist_v = lbase - (hmoist × lheel 2 / 2) / Amoist = 2.25 ft

- Distance to horizontal component; xmoist_h = heff / 3 = 2.167 ft

Area of base soil; Apass = dcover × ltoe = 0.75 ft2

- Distance to vertical component; xpass_v = lbase - (dcover × ltoe× (lbase - ltoe / 2)) / Apass = 0.25 ft

- Distance to horizontal component; xpass_h = (dcover + hbase) / 3 = 1 ft

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Area of excavated base soil; Aexc = hpass × ltoe = 0.417 ft2

- Distance to vertical component; xexc_v = lbase - (hpass × ltoe× (lbase - ltoe / 2)) / Aexc = 0.25 ft

- Distance to horizontal component; xexc_h = (hpass + hbase) / 3 = 0.778 ft

Using Rankine theory

Active pressure coefficient; KA = (1 - sin(φr)) / (1 + sin(φr)) = 0.307

Passive pressure coefficient; KP = (1 + sin(φb)) / (1 - sin(φb)) = 3.255

From IBC 2018 cl.1807.2.3 Safety factor

Load combination 1; 1.0 × Dead + 1.0 × Live + 1.0 × Lateral earth

Sliding check

Vertical forces on wall

Wall stem; Fstem = Astem × γstem = 765 plf

Wall base; Fbase = Abase × γbase = 675 plf

Moist retained soil; Fmoist_v = Amoist × γmr = 1013 plf

Base soil; Fexc_v = Aexc × γb = 50 plf

Total; Ftotal_v = Fstem + Fbase + Fmoist_v + Fexc_v = 2503 plf

Horizontal forces on wall

Surcharge load; Fsur_h = KA × SurchargeL × heff = 120 plf

Line loads; FP_h = PL1 = 50 plf

Moist retained soil; Fmoist_h = KA × γmr × heff 2 / 2 = 876 plf

Total; Ftotal_h = Fsur_h + FP_h + Fmoist_h = 1046 plf

Check stability against sliding

Base soil resistance; Fexc_h = KP × γb × (hpass + hbase)2 / 2 = 1063 plf

Base friction; Ffriction = Ftotal_v × tan(δbb) = 911 plf

Resistance to sliding; Frest = Fexc_h + Ffriction = 1974 plf

Factor of safety; FoSsl = Frest / Ftotal_h = 1.887; > 1.5

PASS - Factor of safety against sliding is adequate

Overturning check

Vertical forces on wall

Wall stem; Fstem = Astem × γstem = 765 plf

Wall base; Fbase = Abase × γbase = 675 plf

Moist retained soil; Fmoist_v = Amoist × γmr = 1013 plf

Base soil; Fexc_v = Aexc × γb = 50 plf

Total; Ftotal_v = Fstem + Fbase + Fmoist_v + Fexc_v = 2503 plf

Horizontal forces on wall

Surcharge load; Fsur_h = KA × SurchargeL × heff = 120 plf

Line loads; FP_h = PL1 = 50 plf

Moist retained soil; Fmoist_h = KA × γmr × heff 2 / 2 = 876 plf

Base soil; Fexc_h = max(-KP × γb × (hpass + hbase)2 / 2, -(Fmoist_h + Fsur_h + FP_h)) = -1046 plf

Total; Ftotal_h = Fsur_h + FP_h + Fmoist_h + Fexc_h = 0 plf

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Overturning moments on wall

Surcharge load; Msur_OT = Fsur_h × xsur_h = 389 lb_ft/ft

Line loads; MP_OT = abs(PL1) × (p1 + tbase) = 500 lb_ft/ft

Moist retained soil; Mmoist_OT = Fmoist_h × xmoist_h = 1899 lb_ft/ft

Total; Mtotal_OT = Msur_OT + MP_OT + Mmoist_OT = 2788 lb_ft/ft

Restoring moments on wall

Wall stem; Mstem_R = Fstem × xstem = 765 lb_ft/ft

Wall base; Mbase_R = Fbase × xbase = 1012 lb_ft/ft

Moist retained soil; Mmoist_R = Fmoist_v × xmoist_v = 2278 lb_ft/ft

Base soil; Mexc_R = Fexc_v × xexc_v - Fexc_h × xexc_h = 826 lb_ft/ft

Total; Mtotal_R = Mstem_R + Mbase_R + Mmoist_R + Mexc_R = 4882 lb_ft/ft

Check stability against overturning

Factor of safety; FoSot = Mtotal_R / Mtotal_OT = 1.751; > 1.5

PASS - Factor of safety against overturning is adequate

Bearing pressure check

Vertical forces on wall

Wall stem; Fstem = Astem × γstem = 765 plf

Wall base; Fbase = Abase × γbase = 675 plf

Surcharge load; Fsur_v = SurchargeL × lheel = 90 plf

Moist retained soil; Fmoist_v = Amoist × γmr = 1013 plf

Base soil; Fpass_v = Apass × γb = 90 plf

Total; Ftotal_v = Fstem + Fbase + Fsur_v + Fmoist_v + Fpass_v = 2633 plf

Horizontal forces on wall

Surcharge load; Fsur_h = KA × SurchargeL × heff = 120 plf

Line loads; FP_h = PL1 = 50 plf

Moist retained soil; Fmoist_h = KA × γmr × heff 2 / 2 = 876 plf

Base soil; Fpass_h = max(-KP × γb × (dcover + hbase)2 / 2, -(Fmoist_h + Fsur_h + FP_h)) = -1046 plf

Total; Ftotal_h = max(Fsur_h + FP_h + Fmoist_h + Fpass_h - Ftotal_v × tan(δbb), 0 plf) = 0 plf

Moments on wall

Wall stem; Mstem = Fstem × xstem = 765 lb_ft/ft

Wall base; Mbase = Fbase × xbase = 1012 lb_ft/ft

Surcharge load; Msur = Fsur_v × xsur_v - Fsur_h × xsur_h = -187 lb_ft/ft

Line loads; MP = -(PL1 × (p1 + tbase)) = -500 lb_ft/ft

Moist retained soil; Mmoist = Fmoist_v × xmoist_v - Fmoist_h × xmoist_h = 380 lb_ft/ft

Base soil; Mpass = Fpass_v × xpass_v - Fpass_h × xpass_h = 1069 lb_ft/ft

Total; Mtotal = Mstem + Mbase + Msur + MP + Mmoist + Mpass = 2539 lb_ft/ft

Check bearing pressure

Distance to reaction; x = Mtotal / Ftotal_v = 0.964 ft

Eccentricity of reaction; e = x - lbase / 2 = -0.536 ft

Loaded length of base; lload = 3 × x = 2.893 ft

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Bearing pressure at toe; qtoe = 2 × Ftotal_v / lload = 1820 psf

Bearing pressure at heel; qheel = 0 psf

Factor of safety; FoSbp = Pbearing / max(qtoe, qheel) = 1.923;

PASS - Allowable bearing pressure exceeds maximum applied bearing pressure

RETAINING WALL DESIGN

In accordance with ACI 318-14

Tedds calculation version 2.9.08

Concrete details

Compressive strength of concrete; f'c = 4000 psi

Concrete type; Normal weight

Reinforcement details

Yield strength of reinforcement; fy = 60000 psi

Modulus of elasticity or reinforcement; Es = 29000000 psi

Compression-controlled strain limit; εty = 0.002

Cover to reinforcement

Front face of stem; csf = 1.5 in

Rear face of stem; csr = 2 in

Top face of base; cbt = 2 in

Bottom face of base; cbb = 3 in

From IBC 2018 cl.1605.2 Basic load combinations

Load combination no.1; 1.4 × Dead

Load combination no.2; 1.2 × Dead + 1.6 × Live + 1.6 × Lateral earth

Load combination no.3; 1.2 × Dead + 1.0 × Earthquake + 1.0 × Live + 1.6 × Lateral earth

Load combination no.4; 0.9 × Dead + 1.0 × Earthquake + 1.6 × Lateral earth

X

Z

S te m

Toe Heel

.3

.3

.2

.2

.9

.0

.3

.3

.9

.9

.1

.4

Loading details - Combination No.1 - kips/ft 2

0.2

-0.1

Shear force - Combination No.1 - kips/ft

0.1

0.1

Bending moment - Combination No.1 - kips_ft/ft

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

X

Z

S te m

Toe Heel

0.03

0.03

0.33

0.08

.2

.2

.2

.2

.8

.1

.2

.2

.1

.10 .8

.8

.9

Loading details - Combination No.2 - kips/ft 2

-1.1

1.4

Shear force - Combination No.2 - kips/ft

2.40.3

-1.2

Bending moment - Combination No.2 - kips_ft/ft

X

Z

S te m

Toe Heel

0.02

0.02

0.33

0.05

.2

.2

.2

.2

.4

.9

.2

.2

.0

.0

.8

.8

.0

Loading details - Combination No.3 - kips/ft 2

-1

0.8 1.1

Shear force - Combination No.3 - kips/ft

20.2

-1.1

Bending moment - Combination No.3 - kips_ft/ft

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

X

Z

S te m

Toe Heel

0.330 .2

.2

.1

.1

.7

.3

.2

.20 .6

.6

.7

Loading details - Combination No.4 - kips/ft 2

-0.8

0.6 0.8

Shear force - Combination No.4 - kips/ft

1.40.2

-0.7

Bending moment - Combination No.4 - kips_ft/ft

Check stem design at base of stem

Depth of section; h = 12 in

Rectangular section in flexure - Section 22.3

Design bending moment combination 2; M = 2431 lb_ft/ft

Depth of tension reinforcement; d = h - csr - φsr / 2 = 9.688 in

Compression reinforcement provided; No.5 bars @ 12" c/c

Area of compression reinforcement provided; Asf.prov = π × φsf 2 / (4 × ssf) = 0.307 in2/ft

Tension reinforcement provided; No.5 bars @ 12" c/c

Area of tension reinforcement provided; Asr.prov = π × φsr 2 / (4 × ssr) = 0.307 in2/ft

Maximum reinforcement spacing - cl.11.7.2; smax = min(18 in, 3 × h) = 18 in

PASS - Reinforcement is adequately spaced

Depth of compression block; a = Asr.prov × fy / (0.85 × f'c) = 0.451 in

Neutral axis factor - cl.22.2.2.4.3; β1 = min(max(0.85 - 0.05 × (f'c - 4 ksi) / 1 ksi, 0.65), 0.85) = 0.85

Depth to neutral axis; c = a / β1 = 0.531 in

Strain in reinforcement; εt = 0.003 × (d - c) / c = 0.051753

Section is in the tension controlled zone

Strength reduction factor; φf = min(max(0.65 + 0.25 ×(εt - εty) / 0.003, 0.65), 0.9) = 0.9

Nominal flexural strength; Mn = Asr.prov × fy × (d - a / 2) = 14514 lb_ft/ft

Design flexural strength; φMn = φf × Mn = 13063 lb_ft/ft

M / φMn = 0.186

PASS - Design flexural strength exceeds factored bending moment

By iteration, reinforcement required by analysis; Asr.des = 0.056 in2/ft

Minimum area of reinforcement - cl.9.6.1.3; Asr.mod = 4 × Asr.des / 3 = 0.075 in2/ft

PASS - Area of reinforcement provided is greater than minimum area of reinforcement required

Rectangular section in shear - Section 22.5

Design shear force; V = 1057 lb/ft

Concrete modification factor - cl.19.2.4; λ = 1

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Nominal concrete shear strength - eqn.22.5.5.1; Vc = 2 × λ × √(f'c × 1 psi) × d = 14705 lb/ft

Strength reduction factor; φs = 0.75

Design concrete shear strength - cl.11.5.1.1; φVc = φs × Vc = 11028 lb/ft

V / φVc = 0.096

PASS - No shear reinforcement is required

Horizontal reinforcement parallel to face of stem

Minimum area of reinforcement - cl.11.6.1; Asx.req = 0.002 × tstem = 0.288 in2/ft

Transverse reinforcement provided; No.4 bars @ 12" c/c each face

Area of transverse reinforcement provided; Asx.prov = 2 × π × φsx 2 / (4 × ssx) = 0.393 in2/ft

PASS - Area of reinforcement provided is greater than area of reinforcement required

Check base design at toe

Depth of section; h = 18 in

Rectangular section in flexure - Section 22.3

Design bending moment combination 2; M = 264 lb_ft/ft

Depth of tension reinforcement; d = h - cbb - φbb / 2 = 14.75 in

Compression reinforcement provided; No.4 bars @ 12" c/c

Area of compression reinforcement provided; Abt.prov = π × φbt 2 / (4 × sbt) = 0.196 in2/ft

Tension reinforcement provided; No.4 bars @ 12" c/c

Area of tension reinforcement provided; Abb.prov = π × φbb 2 / (4 × sbb) = 0.196 in2/ft

Maximum reinforcement spacing - cl.7.7.2.3; smax = min(18 in, 3 × h) = 18 in

PASS - Reinforcement is adequately spaced

Depth of compression block; a = Abb.prov × fy / (0.85 × f'c) = 0.289 in

Neutral axis factor - cl.22.2.2.4.3; β1 = min(max(0.85 - 0.05 × (f'c - 4 ksi) / 1 ksi, 0.65), 0.85) = 0.85

Depth to neutral axis; c = a / β1 = 0.34 in

Strain in reinforcement; εt = 0.003 × (d - c) / c = 0.12726

Section is in the tension controlled zone

Strength reduction factor; φf = min(max(0.65 + 0.25 ×(εt - εty) / 0.003, 0.65), 0.9) = 0.9

Nominal flexural strength; Mn = Abb.prov × fy × (d - a / 2) = 14339 lb_ft/ft

Design flexural strength; φMn = φf × Mn = 12905 lb_ft/ft

M / φMn = 0.020

PASS - Design flexural strength exceeds factored bending moment

By iteration, reinforcement required by analysis; Abb.des = 0.004 in2/ft

Minimum area of reinforcement - cl.7.6.1.1; Abb.min = 0.0018 × h = 0.389 in2/ft

FAIL - Area of reinforcement provided is less than minimum area of reinforcement required

Rectangular section in shear - Section 22.5

Design shear force; V = 1004 lb/ft

Concrete modification factor - cl.19.2.4; λ = 1

Nominal concrete shear strength - eqn.22.5.5.1; Vc = 2 × λ × √(f'c × 1 psi) × d = 22389 lb/ft

Strength reduction factor; φs = 0.75

Design concrete shear strength - cl.7.6.3.1; φVc = φs × Vc = 16792 lb/ft

V / φVc = 0.060

PASS - No shear reinforcement is required

GETT LIttle Round Top

Job Ref.

Section

44th NY Retaining Wall

Sheet no./rev.

Calc. by

ARW

Date

6/28/2021

Chk'd by Date App'd by Date

Check base design at heel

Depth of section; h = 18 in

Rectangular section in flexure - Section 22.3

Design bending moment combination 2; M = 1225 lb_ft/ft

Depth of tension reinforcement; d = h - cbt - φbt / 2 = 15.75 in

Compression reinforcement provided; No.4 bars @ 12" c/c

Area of compression reinforcement provided; Abb.prov = π × φbb 2 / (4 × sbb) = 0.196 in2/ft

Tension reinforcement provided; No.4 bars @ 12" c/c

Area of tension reinforcement provided; Abt.prov = π × φbt 2 / (4 × sbt) = 0.196 in2/ft

Maximum reinforcement spacing - cl.7.7.2.3; smax = min(18 in, 3 × h) = 18 in

PASS - Reinforcement is adequately spaced

Depth of compression block; a = Abt.prov × fy / (0.85 × f'c) = 0.289 in

Neutral axis factor - cl.22.2.2.4.3; β1 = min(max(0.85 - 0.05 × (f'c - 4 ksi) / 1 ksi, 0.65), 0.85) = 0.85

Depth to neutral axis; c = a / β1 = 0.34 in

Strain in reinforcement; εt = 0.003 × (d - c) / c = 0.136091

Section is in the tension controlled zone

Strength reduction factor; φf = min(max(0.65 + 0.25 ×(εt - εty) / 0.003, 0.65), 0.9) = 0.9

Nominal flexural strength; Mn = Abt.prov × fy × (d - a / 2) = 15321 lb_ft/ft

Design flexural strength; φMn = φf × Mn = 13789 lb_ft/ft

M / φMn = 0.089

PASS - Design flexural strength exceeds factored bending moment

By iteration, reinforcement required by analysis; Abt.des = 0.017 in2/ft

Minimum area of reinforcement - cl.7.6.1.1; Abt.min = 0.0018 × h = 0.389 in2/ft

FAIL - Area of reinforcement provided…