Item 0001 SOW.pdf

SPECIFICATIONS

FOR

SMYU25-4009 REPAIR STORM DAMAGED SLOPE AND FENCE FOR SOQ, B437

AT

OSAN AB, ROK

51ST CIVIL ENGINEER SQUADRON

TABLE OF CONTENTS

SMYU 25-4009

REPAIR STORM DAMAGED SLOPE AND FENCE FOR SOQ, B437

Contents

1. GENERAL

2. SCOPE OF WORKS (SOW)

3. REFERENCES AND STANDARDS:

4. CONSTRUCTION SCHEDULE INFORMATION:

5. ADDITIONAL REQUIREMENTS:

6. SECURITY REQUIRMENTS:

7. ENVIRONMENTAL REQUIREMENTS:

8. APPENDIX “A”

9. APPENDIX “B”

10. APPENDIX “C”

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STATEMENT OF WORK

1. GENERAL: The work to be performed for completion of this Work Plan project shall be as described in general below.

1.1. The contractor shall provide all labor, tools, equipment, supplies, and any other resources necessary to accomplish the scope of work contained herein and as included in the drawings and specifications.

1.2. All work shall be complete IAW specifications and standards referenced in section 3 and drawings associated with this project.

1.3. Before any components are fabricated and/or integrated into assemblies, or shipped to the site, the contractor shall prepare a complete hardware submittal and receive 51st Civil Engineering Squadron approval prior to the execution of related services. 51st Civil Engineering Squadron shall require the submittals to be delivered electronically in PDF. Catalog cuts, wiring connections, and such other technical specifications or descriptive matters and documentation as may be required to fully describe the equipment and to demonstrate its conformity to the system, shall be submitted with the hardware submittal. The decision of the 51st Civil Engineering Squadron on the acceptability of any submittal shall be final.

1.4. Contract Type: This project is an individual Work Plan Task Order under the Multiple Award Task Order Contract (MATOC) issued by the 411th CSB, Korea. The definition of Work Plan is a task order in which the Government provides 30% of the concept design for the contract, and the contractor is responsible for completing and submitting 100% of the design submittals. The task order proposal submission requirements are as below:

2. SCOPE OF WORKS (SOW)

2.1. CIVIL WORKS

2.1.1. Remove existing concrete retaining wall along the concrete sidewalk.

2.1.2. Remove existing concrete ditch with steel grate cover on top of retaining wall.

2.1.3. Remove 3ea acacia trees, one stump, and bushes on the slope.

2.1.4. Remove existing concrete sidewalk and handrails. With this removal work, some spots of storm drainage beneath the sidewalk might require protection.

2.1.5. Remove all existing concrete grid on the slope of the job site.

2.1.6. Provide earth shoring wall developed by registered geotechnical professional engineer (PE). (PE seal required)

The shoring wall will consist of H-beam, lumbers, wall and earth anchors. (Please refer to DWG C-2) (Approx.

120 linear meters (LM))

2.1.7. Replace existing soil in the slope with structural backfill and compaction for segmental block retaining wall. The extent of soil replacement shall be determined by registered geotechnical PE and be shown in the construction drawing and geotechnical assessment report (GAR). (Approx. 700 cubic meters (CM))

2.1.8. Provide segmental concrete block retaining wall as indicated project drawing (C-1) and geo-grid system, perforated pipe, concrete foundation, filter fabric, and riprap backfill. The retaining wall shall be designed by registered geotechnical PE and the construction drawing (post award) shall require to be sealed by PE. Contractor shall submit GAR developed by registered geotechnical PE and the report shall show the stability and soundness of

Page | 4 retaining wall, earth shoring, and structural backfill & compaction. (Approx. 120LM, 3 meters (M) height) Specification of segmental concrete block and geogrid shall comply with special specification Appendix “B”.

Geotechnical information (boring log) near B437 is attached in Appendix “C” for reference purpose only and contractor shall perform in-site boring (minimum 3ea holes) for shoring & retaining wall design thus GAR shall be developed based on actual soil characteristics of the site. Assumed data shall not be accepted.

2.1.9. Install concrete ditch with steel grate cover on top of the retaining wall and connect to adjacent existing storm drainage. (Approx. 120LM)

2.1.10. Provide metal handrail with painting on top of the retaining wall. (Approx. 120LM)

2.1.11. Replace existing chain link fence with new and connect to existing fence. (Approx. 110LM, same type)

2.1.12. Install steel grate covered ditch along the chain link fence. (Approx. 110LM)

2.1.13. Install 1 EA concrete catch basin and underground reinforced concrete pipe (RCP) to connect to adjacent storm drainage system. (Approx. 40LM)

2.1.14. Provide new concrete sidewalk and metal handrail with paint. (Approx. 120LM, 1.5~1.8M width)

2.1.15. Provide solid sodding for entire slope. (Approx. 1,000 square meters (SM))

2.1.16. Mill and overlay existing asphalt pavement in parking lot. (Approx. 940 SM, 75-millimeter (MM) thickness)

2.1.17. Provide markings for AC pavement after mill & overlay.

2.1.18. Dispose removed concrete structures, asphalt pavement, soil to proper off-base disposal site.

2.1.19. Child-proof safety barricades shall be installed to prevent access to people/residents during the construction period. The government will provide the locations to the contractor of where those safety barricades shall be placed.

3. REFERENCES AND STANDARDS:

3.1. This project shall comply with the “Standard Technical Specifications and Standard Detail Drawings for OMA Projects, Korea” dated 30 November 2015 issued by the Department of the Army, Installation Management Agency, Korea Region Office. The most current specifications (O&MA Specification 2014, Revision-1) and standard drawings are available at the Engineering Flight, 51st Civil Engineer Squadron, Osan AB, Unit 2129, APO AP 96278-2129 and also are located link below.

OMA2014R12015FN2 _ [PROJECT_TOC]

3.2. Unified Facility Criteria (UFC): UFC 3-220-01 Geotechnical Engineering

UFC 3-220-01 Geotechnical Engineering, with Change 2 | WBDG - Whole Building Design Guide

3.3. Unified Facility Criteria (UFC): UFC 3-220-10 Soil Mechanics

UFC 3-220-10 Soil Mechanics (DM 7.1) | WBDG - Whole Building Design Guide

3.4. Other Applicable Specific Specifications for Guides: The project shall comply with “Osan AB Architectural Compatibility Plan dated 01 January 2022” and Chapter 6 of USFK Regulation 201-1, Korean Environmental Governing Standards, and Osan Air Base Hazardous Waste Management Plan.

3.5. Required Design Data (Technical Evaluation Purpose)

http://www.usfk.mil/Resources/ContractingwithUSFK.aspx https://www.usfk.mil/portals/105/documents/contracting/newcontract/2014-oma-specs_revision-1.pdf https://www.wbdg.org/dod/ufc/ufc-3-220-01 https://www.wbdg.org/dod/ufc/ufc-3-220-10

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• Cover pages(s) such as title sheet, project location, schedule of drawings

• Site plan

• Removal plan

• Shoring plan, profile, section, and details

• Segmental concrete block retaining wall profile, section, and details

• Grading plan and section

• Storm drainage system

• Chain link fence

• Sidewalk and handrail plan and details

• The layouts of the playground equipment marked with the safety distance

• Material information on playground equipment & rubber flooring material (Catalog cuts including Korean

Playground Equipment Safety Certificates & Test Reports)

• Detail/section for playground (base course and concrete pad w/weep holes, and rubber flooring)

• Detail for sunshade with concrete footings

• Drainage system plan w/details for sodding

3.6. Required Design Data (100% Drawings and Report, Post Award)

• Cover pages(s) such as title sheet, project location, schedule of drawings

• Site plan

• Removal plan

• Shoring plan, profile, section, and details

• Segmental concrete block retaining wall profile, section, and details

• Grading plan and section

• Storm drainage system

• Chain link fence

• The layout of the playground equipment marked with the safety distance

Page | 6

• Detail/section for playground (base course and concrete pad w/weep holes, and rubber flooring)

• Detail for sunshade with concrete footings

• Drainage system plan w/details for sodding

• Sidewalk and handrail plan and details

• Geotechnical Assessment Report (GAR)with P.E. seal

• Asphalt mill & overlay plan and section

• Road marking plan and details

3.7. 100% drawing & GAR, and AF Form 3000s shall require to be submitted no later than 15 days after post-award meeting.

4. CONSTRUCTION SCHEDULE INFORMATION:

KEY INFORMATION FOR CONSTRUCTION SCHEDULE

Project Site Base Area Close to senior officer quarter (SOQ)

Contract Type MATOC – Work Plan 411TH CSB

Performance of Period (PoP) 180 Days (After Post Award Meeting)

Temporary Airfield Construction Waiver Required (TACW)

No

Risk Assessment (RA) Required No

Phasing Work Required No

Military Training Event Anticipated

Yes Minimum 14 days of Military Training Event anticipated during PoP

Restricted Area Escort Required No

4.1. Working Hours: All work shall be accomplished in such a manner that minimum inconvenience shall be caused to the Government. All work shall be accomplished during normal duty hours from 0730 to 1630 hours, excluding weekends, U.S. and ROK holidays. See MATOC section H-4 for holiday list. The contractor will only be allowed access to the work area during normal base working hours and when building staff and employees are present. Any requests to work outside of normal working hours must be submitted in writing to the Contracting Officer Representative (COR) at least seven (7) days in advance and approved. The Government reserves the right to change hour of operation due to military training events such as exercises and wing down days. Contractor will be notified 72 hours in advance of any required changes in work schedule.

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4.2. Military Training Events are anticipated to occur during the construction period as indicated in Table above. During training event, contractor will not be allowed to access the project site. Contractor shall consider these conditions in their proposal. Contractors will be given 72 hours’ notice of work stoppage without incurring penalty to the Government.

4.3. Phasing Plan: Phasing plan shall be required for all road work projects or anything interfering with operations/large base functions (Airfield, BX, Gym, etc). Specific phasing shall not be pre-determined, but contractor shall submit a plan for approval by construction OIC/NCOIC. Three phases shall be required as a minimum. This minimum can be waived by the construction

OIC/NCOIC.

4.4. Time on target of the site release date and phasing work plan will be discussed with user and COR at the pre-con meeting after award.

4.5. Due to the mission requirements on the installation, there may be occasional restrictions on normal working hours and site access. Please be aware that site access windows are subject to change without prior notice. Contractors are advised to take this work environment into account when preparing their proposals.

4.6. The following shall be submitted via email to the COR within 10 days of project award:

4.6.1. Dates of material/product testing

4.6.2. Requests to operate equipment taller than 20 feet (6 meters) with timeline of use and exact height required

4.6.3. Any period of time contractor is not able to perform (more severe than the adverse weather anticipated, curing time, etc.)

4.6.4. Any expected utility outages, road closures, or other impacts on base users that could affect their work

4.6.5. Requests for Information

4.7. Any correspondence sent from COR to Contractor via email shall be replied to within one work week.

4.8. In order to be issued NTP, contractor has to obtain an approval for key submittals (QC plan, Safety Plan, Initial Project Schedule) no later than 14 days after a post-award meeting.

5. ADDITIONAL REQUIREMENTS:

5.1. Submittals: Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. The following shall be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES of O&MA Specs

5.1.1. All submittals shall be submitted to the contracting officer representative with written confirmation of receipt within 30 calendar days after project acceptance. Any rejected submittal shall be re-submitted within 10 calendar days. If any submittal is rejected more than once, the contractor shall meet with the contracting officer representative and project engineer to clarify. Any further rejections of the same submittal shall meet with the same action.

5.2. At least one fluent English speaker must be on the site whenever work is being done; Contractor must be able to communicate with project inspectors at any time during approved working hours. Contractor will have the COR’s phone number and shall contact the COR for the following reasons:

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5.2.1. Damage caused by Contractor within the installation.

5.2.2. Differing site conditions from Contract documents requiring adjustments.

5.2.3. Any Request for Information (RFI) during project execution.

5.2.4. Changes to project timeline to include weather events, delays in material delivery, or lack of workers. Changes to project scheduled shall be relayed to COR within 24 hours.

5.3. Laydown area policy and requirements: Laydown area to be coordinated with the COR.

5.4. The contractor shall provide, install, and maintain all necessary signs, lights, flares, barricades, markers, cones and shall take all necessary precautions for the protection and safety of the public and/or military traffic and operations.

5.4.1. The Contractor’s Safety Representative shall be contactable and able to arrive on site within two (2) hours of being requested.

5.5. Site Cleanliness and Cleanup: The Contractor shall keep the work areas in or near unit free from accumulations of waste material and rubbish. Contractor’s tools and equipment will not be placed directly on unprotected surfaces. Upon completion of work, the Contractor shall leave the work site and premises in a clean and neat condition. The Contractor shall not place trash in refuse containers at the unit or any location other than the designated containers at his on base facility.

5.6. When contractors install new underground infrastructures, they shall notify COR before covering excavated area so that 51st CES GeoBase team can collect as-built geo-referenced data.

5.7. Contractor shall coordinate with COR for any construction work on the Airfield or within Restricted Areas for access and/or escort requirements. It is common for users to need partial access to the work site during construction.

Contractor shall plan work phasing to facilitate ongoing mission execution upon government request.

5.8. The contractor shall be responsible for verifying the location, size and inverts of all existing utilities and shall protect all such utilities at all times, unless otherwise indicated. Existing utilities whether shown on the drawings or not which have been damaged as a result of the construction work, shall be restored immediately to their original or better condition and shall be paid for by the contractor.

5.9. Whenever connections to existing utilities or where new utilities cross existing utilities are shown, the contractor shall carefully expose the utility by hand excavation to verify their locations and depths prior to excavating trenches for the new utility lines.

5.10. Whenever any change in alignment or grade for the proposed utilities is required due to unforeseen conflict with other utilities, the contractor shall inform the COR who will contact the contracting officer for remedial action.

5.11. As-Built Drawings: The Government will at its discretion withhold a portion or all of the final payment until the As-Built drawings have been submitted.

5.12. Warranty: Upon completion of task order, warranty period will apply unless a different timeframe is listed in the

RFP.

5.13. Final Cleanup: Upon completion of task order, construction site shall be cleaned of any spills and debris, all contractor equipment shall be removed, and any restoration efforts made to leave the site in a clean and orderly condition.

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5.14. Debris, waste and loose material (including dust and dirt) capable of causing damage to aircraft operations or being ingested in jet engines shall not be allowed on active aircraft movement areas or adjacent grassed areas.

Materials observed to be within these areas shall be removed immediately and/or continuously by the Contractor during the work.

5.15. Objects (whether or not marked or flagged) or activities anywhere on or in the vicinity of airfield which could be distracting, confusing, or alarming to pilots during aircraft operations are prohibited during all the time of the repair work.

5.16. The contractor shall provide, install, and maintain all necessary signs, lights, flares, barricades, markers, cones and shall take all necessary precautions for the protection and safety of the public and/or military traffic and operations.

5.17. Coverage must be installed when construction materials are stocked on site.

5.18. All ground surface disturbed by construction shall be restored to its original condition.

5.19. Construction signs, lights, and barricades shall be installed at locations necessary to maintain a safe work site condition.

5.20. Contractor shall be responsible for any damage or debris outside of their construction site limits that directly impact the existing use of the remaining pool facilities and deck during their operating hours. The government will provide formal notification to the contractor if these conditions are met and the contractor needs to mobilize to clean outside of their site.

5.21. Runway Operations. It is the intention of the Government to close the runway to all aircraft traffic while marking operations are ongoing. However, work may be interrupted to provide a runway for aircraft in an emergency or when a special or unscheduled mission is assigned. If the runway is needed for aircraft operations, the Contractor shall remove all equipment from the operational surfaces of the airfield and beyond the hold line within 15 minutes of notification to clear the runway. A scheduled landing or departure that has been identified to the Contractor prior to the start of the Contractor’s work shift shall not be considered an interruption.

6. SECURITY REQUIRMENTS:

6.1. Contractor’s personnel or any representative of the contractor entering installation/base shall abide by all security regulations imposed by Installation Commander or Base Commander at all times and shall be subject to security checks.

Contractor’s personnel and property shall be subject to search and seizure upon entering the confines of the installation/base, while on, and upon leaving confines of the installation/base.

6.2. The training IWATCH/EAGLE EYES/AT Level I shall be completed within 30 calendar days of contract award and within 30 calendar days of new employees commencing performance with the results reported to the COR NLT 45 calendar days after contract award.

6.3. ALERTS: During military alerts or special operations, the contractor may not be authorized on base or in the work site. When the contractor is prohibited from access to the base or work site for one (1) day or less per month, no adjustment in the contract time shall be made. When the contractor is prohibited access for more than one (1) day per month, adjustments shall be made in accordance with applicable clauses of the General Provisions.

6.4. Physical Security: The Contractor shall be responsible for safeguarding all government property provided for Contractor use. At the close of each work period, government facilities, equipment, and materials shall be secured;

lights, and water turned off, adjust heat and air conditioning appropriately, and all doors and windows secured.

6.5. BASE PASSES: The contractor shall be required to obtain base passes to Osan Air Base to perform the requirements

Page | 10 of this contract. The contractor shall be responsible to submit a base pass request no later than five (5) calendar days after award of this contract. It should be noted that it can take up to 30 days or more to process base pass paperwork. It shall be the responsibility of the contractor to prepare the necessary base pass paperwork to include USFK Form 82-E, USFK Form 225EK-E, family history register, local register, etc. for each individual requiring access to Osan Air Base. The contractor shall also be authorized to receive vehicle passes for each of the contractor’s vehicles used in the performance of the requirements of this contract. It shall be the responsibility of the contractor to prepare the necessary paperwork to include USFK Form 195EK-E, vehicle registration, vehicle insurance, certificate of safety inspection and a copy of driver’s license for each vehicle requiring access to Osan Air Base. The contractor shall prepare a cover letter listing each individual, skill, escort privileges, vehicle type, vehicle registration number, etc. The contractor shall also provide the COR with two (2) copies of this request letter, with carbons, to include the top copy with original signatures. Escort privileges will be justified and limited to specific needs for contract completion and at the discretion and approval of the sponsor and requesting authorities identified in Block 13 and Section III of the USFK Form 82- E, Application for Installation/Base Access. The contractor shall not be authorized to perform any portion of the contract requirements until such time that the contractor has processed the necessary base pass paperwork for entry onto Osan Air Base. The COR shall not provide or be responsible to provide the contractor with escorts during performance of any part of this contract.

All of the above documents shall be turned in to the COR for processing with the 51st Security Forces.

6.6. AT/OPSEC REQUIREMENTS: The contractor and all associated sub-contractors will practice Operations Security.

The contractor shall not talk about work outside of the work area nor discuss the work being performed on social media.

The contractor shall not take pictures/video (to include operation of dashcams or other recording devices in contractor operated vehicles) inside sensitive locations without prior coordination with the organization's OPSEC representative and contracting officer representative. It will be the responsibility of the contractor to safeguard all documents provided.

Documents will be stored away from view when not being used. Documents, media, drawings, and other associated material that are no longer needed must be destroyed via approved methods.

6.7. Key Control: The Contractor shall establish and implement methods of ensuring that all keys issued are not lost or misplaced and are not used by unauthorized persons.

6.7.1. The Contractor shall immediately report to the COR any occurrences of lost or duplicated keys. The Contractor shall re-key or replace keys or reimburse the government for replacement of locks or re-key as a result of Contractor losing keys. In the event a master key is lost or duplicated, all keys and locks for that system shall be replaced or reimburse the government for replacement of locks or re-key.

7. ENVIRONMENTAL REQUIREMENTS:

7.1. Construction debris and litter from work areas within the construction limits of the project site shall be collected and placed in watertight dumpsters at least weekly regardless of whether the litter was generated by the Contractor, the public, or others. Collected litter and debris shall not be placed in or next to drain inlets, storm water drainage systems or watercourses.

7.2. Solid waste storage areas shall be located at least 15 m (50 ft.) from drainage facilities and watercourses and shall not be located in areas prone to flooding or ponding.

7.3. Place hazardous materials/waste containers in secondary containment. Container to store construction debris has to have water-proof and leak-proof lid.

7.4. The contractor shall submit the HAZMAT information (especially all paints/coating) and AF Form 3952 IAW AFMAN 32-7002, Chemical Hazardous Material Request Authorization along with a copy of Safety Data Sheet to obtain HAZMAT approval from BEE, Safety, and Environmental Office. All paint products should be lead free.

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7.5. For welding and brazing: Perform activities indoors. Cover nearby drain inlets and sweep-up metal particulates after each event.

7.6. The Contractor shall comply with USFKM 4715.05, Korea Environmental Governing Standards (KEGS), Enclosure N, Solid Waste, specific standards for construction waste. The Contractor shall report the metric tons for construction and demolition (C&D) debris, including cost deposited in a landfill, incinerated, or diverted (recycled), respectively, to Environmental Office thru COR every 30 days for each project site. The Contractor shall use the C&D container (Roll-Off type) with water-proof lid and keep it always covered except when in use.

7.7. The contractor shall use lead free coatings and paints. In addition, all surface coating/painting shall be applied by brush or roller. Using spray equipment is prohibited for minimization of air emissions unless otherwise specified or recommended by the paint manufacturer.

7.8. The Contractors are prohibited by 10 U.S.C. 2692 from storage, treatment, or disposal of any contractor owned hazardous waste on installation. The Contractors must get approval from HW Program Manager to store Hazardous Waste generated on-site in connection with a contract activity. HW storage will be on a temporary basis prior to disposal from Osan AB.

7.9. The contractors need either 1) a permit to store hazardous waste while they are working on the installation or 2) they need to remove the hazardous waste from base within 24 hours. In either case, for disposal, the contractor needs to dispose of the waste in accordance with local regulations and provide a stamped manifest or other documentation demonstrating appropriate disposal to Environmental Office.

7.10. The Contractor shall implement Best Management Practices (BMP) specified on Table H-9 of the KEGS and Appendix E of the Osan AB Storm Water Pollution Prevention Plan for construction sites.

7.11. A dust controls plan shall be developed/implemented to take appropriate measure to minimize the generation of dust as a result of their works, operations, and activities during and after construction until the site is reclaimed. Standard dust control Best Management Practices (BMPs) for dust generating activities shall be implemented during construction.

7.12. Contractor will ensure that spills will be prevented from release as defined by USFK Regulation 201-1" to “USFKM 4715.05, KEGS, Enclosure L, Spill Prevention and Response Plan or discharge event reportable to the ROK, Spills of hazardous substances in excess of the reportable quantity (RQ) listed in KEGS Appendix B. Table B-4, POL or liquid or semi-liquid hazardous material, hazardous waste, or hazardous substance in excess of 400 liters (110 gallons), other solid hazardous material in excess of 225 kg (500 pounds), combination of POL and liquid, semi-liquid and solid hazardous material, waste or substance in excess of 340 kg (750 pounds), any wastewater discharge that does not meet criteria in KEGS Chapter 4) in the case of release, the Contractor shall immediately report the incident to the COR. The Contractor shall be liable for all Contractor caused spills, remediation, and shall maintain the capability to respond to and control spills less than 100 gallons.

7.13. Scrap metal shall be collected by the contractor for disposal and sale through the Osan AB Qualified Recycling Program (QRP) in accordance with DOD Instruction 4715.23. The Contractor shall appropriately segregate and place the scrap metal to the location that QRP manager designates on base.

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8. APPENDIX “A”

LIST OF CONTRACT DRAWINGS

DWG NO. SHT NO. REF NO. DESCRIPTION

1 OF 4 T-01 TITLE PAGE AND PROJECT LOCATION

2 OF 4 C-01 SITE PLAN

3 OF 4 C-02 WALL & SHORING CONCEPTUAL DWG

4 OF 4 C-03 EXISTING STORM DRAINAGE MAP

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9. APPENDIX “B”

SPECIAL SPECIFICATION

SEGMENTAL CONCRETE BLOCK RETAINING WALL

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO M 252 (2009) Standard Specification for Corrugated Polyethylene Drainage Pipe AASHTO M 288 (2006) Standard Specification for Geotextile Specification for Highway Applications

ASTM INTERNATIONAL (ASTM)

ASTM C 1262 (2010) Standard Test Method for Evaluating the Freeze-Thaw Durability of Manufactured Concrete Masonry Units and Related Concrete Units ASTM C 136 (2006) Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates ASTM C 1372 (2009) Standard Specification for Dry-Cast Segmental Retaining Wall Units ASTM C 140 (2010) Standard Test Methods for Sampling and Testing Concrete Masonry Units and Related Units ASTM C 920 (2010) Standard Specification for Elastomeric Joint Sealants ASTM C 94/C 94M (2010) Standard Specification for Ready-Mixed Concrete ASTM D 1241 (2007) Materials for Soil-Aggregate Subbase, Base, and Surface Courses ASTM D 1556 (2007) Density and Unit Weight of Soil in Place by the Sand-Cone Method ASTM D 2487 (2010) Soils for Engineering Purposes (Unified Soil Classification System) ASTM D 2488 (2009a) Description and Identification of Soils (Visual-Manual Procedure) ASTM D 4355 (2007) Deterioration of Geotextiles from Exposure to Light, Moisture and Heat in a Xenon-Arc Type Apparatus ASTM D 448 (2008) Sizes of Aggregate for Road and Bridge Construction ASTM D 4491 (1999a; R 2009) Water Permeability of Geotextiles by Permittivity ASTM D 4595 (2009) Tensile Properties of Geotextiles by the Wide-Width Strip Method ASTM D 4632 (2008) Grab Breaking Load and Elongation of Geotextiles ASTM D 4751 (2004) Determining Apparent Opening Size of a Geotextile ASTM D 4873 (2002; R 2009) Identification, Storage, and Handling of Geosynthetic Rolls and Samples ASTM D 5321 (2008) Determining the Coefficient of Soil and Geosynthetic or Geosynthetic and Geosynthetic Friction by the Direct Shear Method ASTM D 6638 (2007) Determining Connection Strength Between Geosynthetic Reinforcement and Segmental Concrete Units (Modular Concrete Blocks) ASTM D 6938 (2010) Standard Test Method for In-Place Density and Water Content of Soil and Soil-Aggregate by Nuclear Methods (Shallow Depth) ASTM D 698 (2007e1) Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400 ft-lbf/cu. ft. (600 kN-m/cu. m.))

KOREAN INDUSTRIAL STANDARDS (KS)

KS F 2311 (2001) Test method for soil density by the sand replacement method KS F 2324 (2006) Method of classification of soils for engineering purposes KS F 2502 (2005) Standard test method for sieve analysis of fine and coarse aggregates

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KS K 0520 (2009) Textiles - Tensile properties of fabrics - Determination of strength and elongation：Grab method KS K 0746 (2009) Test method of weatherability of geotextiles：Xenon - arc method KS K 0754 (2007) Test method for apparent opening size of geotextile - Dry method KS K ISO 10319 (2007) Geotextiles - Wide-width tensile test GEOSYNTHETIC INSTITUTE (GSI) GSI GRI GG6 (1996) Grip Types for Use in Wide Width Testing of Geotextiles and Geogrids GSI GRI GT6 (1992) Geotextile Pullout

NATIONAL CONCRETE MASONRY ASSOCIATION (NCMA)

NCMA TR127 (2010b) Design Manual for Segmental Retaining Walls NCMA TR160 (1998) Seismic Design Manual for Segmental Retaining Walls

U.S. FEDERAL HIGHWAY ADMINISTRATION (FHWA)

FHWA NHI-00-043 (2004) Mechanically Stabilized Earth Walls and Reinforced Soil Slopes Design and Construction Guidelines (ISDDC)

1.2 DEFINITIONS

1.2.1 Blocks

Segmental concrete retaining wall units will be referred to as blocks.

1.2.2 Drainage Aggregate

Granular soil or aggregate which is placed within, between, and/or immediately behind segmental concrete units.

1.2.3 Fill

Soil or aggregate placed in, behind, or below the wall will be referred to as fill.

1.2.4 Reinforced Fill

Soil which is placed and compacted within the neat line volume of reinforcement as outlined on the plans.

1.2.5 Retained Fill

Soil which is placed and compacted behind the reinforced fill.

1.2.6 Reinforcement

Reinforcement shall consist of a geogrid or a geotextile product manufactured for use as reinforcing. Reinforcement shall not include steel products.

1.3 SYSTEM DESCRIPTION

This work element includes engineering services in addition to the construction requirements. The Contractor is responsible for engineering services that include design of the wall in accordance with the National Concrete Masonry Association design method, and providing shop drawings indicating all features of the complete design.

1.3.1 Design Requirements

Complete all stability analyses in accordance with either the NCMA TR127, or the Federal Highway Administration/AASHTO method detailed in FHWA NHI-00-043. Only one method shall be followed for the complete design, including reinforcement design strength, layout, stability calculations, and seismic effects. The segmental retaining wall system shall be designed under the direction of, and be signed by, a registered professional engineer. The engineer shall visit the job at least once during the construction.

1.3.2 Layout

Shop drawings shall reflect all information needed to fabricate and erect the walls including the leveling pad elevations; the shape and dimensions of wall elements; the number, size, type, and details of the soil reinforcing system and anchorage; and

Page | 15 identification of areas requiring coping. The design and layout of the internal reinforcement shall be subject to the following:

a. All features indicated in the contract documents shall be incorporated in the final design and construction.

b. The leveling pad elevations may vary, but shall be no higher than the embedment depth profile shown.

c. Each reinforcement level shall run as continuous as practical throughout the profile. If a geotextile filter is present, the reinforcement shall be laid out so that interference with the geotextile is minimized.

d. Any reinforcement not placed with the machine direction as the design reinforcement direction shall be identified on the shop drawings.

e. Reinforcement attached to the wall facing shall not combine geogrid and geotextile, nor products from different manufacturers, within one wall. The number of reinforcement products shall be limited to avoid confusion in placement. For walls under 3.5 meters (12 feet) high, all reinforcement shall be the same grade and strength (i.e. design with one reinforcement strength).

1.4 SUBMITTALS

Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government.

Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings Shop Drawings; G

Fabrication and installation drawings. Include with the shop drawings all items described under paragraph SEGMENTAL RETAINING WALL DESIGN.

SD-03 Product Data

Components and Equipment Descriptive technical data on the blocks, wall caps, masonry adhesive, reinforcement, geotextile filter materials and equipment to be used. The submittal shall include all material properties specified under PART 2 PRODUCTS. The submittal shall also include a copy of any standard manufacturer's warranties for the products.

Supplier Qualifications

Manufacturer's Representative Documentation showing that the installer and supplier meet the qualifications listed.

Soil Testing

Reinforcement Testing Testing data specific to the blocks and reinforcement to be supplied.

a. The shear strength between blocks shall be established in accordance with NCMA TR127.

b. The connection strength between the blocks and the reinforcement shall be established in accordance with ASTM D 6638. If the FHWA design method is used, the modifications in FHWA NHI-00-043 shall be implemented.

c. The coefficient for direct shear of the reinforcement on a soil similar in gradation and texture to the material that will be used for fill in the reinforced zone shall be established in accordance with ASTM D 5321.

d. The coefficient of interaction for pull-out resistance of the reinforcement in a soil similar in gradation and texture to the material that will be used for fill in the reinforced zone shall be established in accordance with GSI GRI GT6.

Calculations; G

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Calculations of the design strength for the reinforcement in accordance with the NCMA or FHWA design method. The ultimate strength or index strength shall be based on the minimum average roll value tensile strength of the product using the wide width strength test in ASTM D 4595 or KS K ISO 10319. The calculation shall itemize each reduction factor and include backup data to justify each reduction factor. Design calculations, including computer output data and program documentation. The calculations shall include all items described under PARAGRAPH: SEGMENTAL RETAINING WALL DESIGN.

SD-04 Samples

Segmental Concrete Units Two samples of each proposed block. Each sample shall be typical of the size, texture, color, and finish.

Reinforcement

Samples of each type of reinforcement. The samples shall be labeled and have a minimum size 200 by 250 mm (8 by 10 inches). Geogrid shall include at least 2 apertures (3 junctions) in each direction.

SD-07 Certificates

Reinforcement Affidavit certifying that the reinforcement meets the project specifications. The affidavit shall be signed by an official authorized to certify on behalf of the manufacturer and shall be accompanied by a mill certificate that verifies physical properties were tested during manufacturing and lists the manufacturer's quality control testing. If the affidavit is dated after award of the contract and/or is not specific to the project, the supplier shall attach a statement certifying that the affidavit addressed to the wholesale company is representative of the material supplied. The documents shall include a statement confirming that all purchased resin used to produce reinforcement is virgin resin. The mill certificate shall include the tensile strength tested in accordance with ASTM D 4595 or KS

K ISO 10319.

1.5 QUALITY ASSURANCE

1.5.1 Contractor Qualifications

furnish Components and equipment that are standard products of a manufacturer regularly engaged in the manufacturing of products that are of a similar material, design and workmanship. The standard products shall have been in satisfactory commercial or industrial use for 2 years before bid opening. The job foreman or the company directly responsible for the wall installation shall have completed a minimum of 10 segmental concrete retaining wall projects at least 2 years experience.

1.5.2 Supplier Qualifications

Suppliers of segmental retaining wall system components shall have demonstrated experience in the supply of similar size and types of segmental retaining walls on previous projects.

1.5.3 Manufacturer's Representative Provide a qualified and experienced representative from the block or reinforcement manufacturer available on an as-needed basis during the wall construction. The representative shall visit the site for consultation at least once during construction as requested by the Contracting Officer.

1.6 DELIVERY, STORAGE, AND HANDLING

Check products upon delivery to assure that the proper material has been received and is undamaged. For geosynthetics, the guidelines presented in ASTM D 4873 shall be followed.

1.6.1 Segmental Concrete Units and Wall Caps Protect blocks from damage and exposure to cement, paint, excessive mud, and like materials. Check materials upon delivery to assure that the block dimensions are within the tolerances specified.

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1.6.2 Geosynthetic Labeling

Each roll shall be labeled with the manufacturer's name, product identification, roll dimensions, lot number, and date manufactured.

1.6.3 Geosynthetic Handling

Geosynthetic rolls shall be handled and unloaded by hand, or with load carrying straps, a fork lift with a stinger bar, or an axial bar assembly. Geosynthetic rolls shall not be dragged, lifted by one end, lifted by cables or chains, or dropped to the ground.

1.6.4 Geosynthetic Storage

Protect geosynthetics from cement, paint, excessive mud, chemicals, sparks and flames, temperatures in excess of 70 degrees C (160 degrees F), and any other environmental condition that may degrade the physical properties. If stored outdoors, the rolls shall be elevated from the ground surface. Geosynthetics, except for extruded grids, shall be protected with an opaque waterproof cover. Geosynthetics shall be delivered to the site in a dry and undamaged condition. Geotextiles shall not be exposed to direct sunlight for more than 7 days.

PART 2 PRODUCTS

2.1 SEGMENTAL CONCRETE UNITS

2.1.1 Architectural requirements

a. Face color - Indicated on the drawings.

b. Face Texture - Indicated on the drawings.

c. Face Appearance - Indicated on the drawings.

d. Batter - Blocks shall be engaged to the block below by use of keys, lips, pins, clips, or other reliable mechanism to provide a consistent wall batter between 1H:6V and 1H:16V.

e. Block Size - a minimum of 0.06 square meters (2/3 square foot) of face area, and minimum 150 mm (6 inches) height.

f. Bond configuration - No bond configuration is required for straight face blocks. Beveled or sculptured face blocks shall be designed to stack with a half-bond (joints located at midpoint of vertically adjacent blocks). The block edges shall be finished so that vertical joints are flush.

2.1.2 Structural requirements

The blocks shall be manufactured to the requirements of ASTM C 1372 or ASTM C 94/C 94M, except for the following modifications:

a. Minimum 28-day compressive strength of 31 MPa (4,500 psi), based on net area in accordance with ASTM C 140.

b. A maximum moisture absorption rate of 145 kg/m3 (9 pounds per cubic foot), in accordance with ASTM C 140.

c. The minimum oven dry density of concrete shall be 2000 kg/m3 (125 pounds per cubic foot).

d. The blocks shall provide a minimum of 400 kg/square meter (80 pounds per square foot) of wall face area (determined without void filling).

e. For freeze-thaw durability tested in accordance with ASTM C 1262, specimens shall comply with either of the following: (1) the weight loss of each of 5 specimens after 100 cycles shall not exceed 1 percent; or (2) the weight loss of each of 5 specimens after 150 cycles shall not exceed 1.5 percent.

2.1.3 Wall Caps

Segmental concrete block units shall be placed as caps on top of all segmental concrete retaining walls. The cap blocks shall have a color and texture on exposed faces to match that of the other blocks and meet the requirements for the other blocks except that the minimum height shall be 75 mm (3 inches). Each cap block shall have abutting edges saw cut or formed to provide tight, flush abutting joints with no gaps in the joints when placed end to end in the alignment shown on the drawings.

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2.2 REINFORCEMENT

2.2.1 Geogrid Reinforcement

Geogrid shall be a geosynthetic manufactured for reinforcement applications. The geogrid shall be a regular network of integrally connected polymer tensile elements with aperture geometry sufficient to permit significant mechanical interlock with the surrounding soil, aggregate, or other fill materials. The geogrid structure shall be dimensionally stable and able to retain its geometry under manufacture, transport and installation. The geogrid shall be manufactured with 100 percent virgin resin consisting of polyethylene, polypropylene, or polyester, and with a maximum of 5 percent in-plant regrind material.

Polyester resin shall have a minimum molecular weight of 25,000 and a carboxyl end group number less than 30. Polyethylene and polypropylene shall be stabilized with long term antioxidants.

2.2.2 Geotextile Reinforcement

Geotextile shall be a pervious sheet of polymeric material and shall consist of long-chain synthetic polymers composed of at least 95 percent by weight polyethylene, polypropylene, or polyesters. The geotextile shall be manufactured with 100 percent virgin resin, and with a maximum of 5 percent in-plant regrind material. Geotextile shall be formed into a network such that the filaments or yarns retain dimensional stability relative to each other, including the selvages. Polyester resin shall have a minimum molecular weight of 20,000 and a carboxyl end group number less than 50. Polyethylene and polypropylene shall be stabilized with long term antioxidants. For survivability during installation, and in addition to installation damage used in calculating the long term design strength, the geotextile shall meet the minimum requirements in AASHTO M 288 Class 1, and shall have a minimum mass per unit area of 270 g/m2 (8 ounces per square yard).

2.2.3 Reinforcement Properties

The reinforcement shown in the approved shop drawing submittal shall meet the design strength requirements used in the design, and shall meet the properties listed in Table 1.

Reinforcement strength requirements represent minimum average roll values in the machine direction.

TABLE 1. REINFORCEMENT PROPERTIES

PROPERTY REQUIREMENT TEST DESIGNATION

Permittivity (geotextiles) 0.5 per second ASTM D 4491 UV Resistance 70 percent after ASTM D 4355 500 hours or KS K 0746

2.2.3.1 Long Term Design Strength

The long term design strength shall be based on reduction factors for installation damage and durability that are applicable to the fill that will be used. Minimum reduction factors for durability include: 1.1 for polyethylene and polypropylene geosynthetics, 1.15 for coated polyester geogrids, and 1.6 for polyester geotextiles. The creep reduction factor must be consistent with the test procedure used for determining the ultimate strength.

2.3 GEOTEXTILE FILTER

Geotextiles used as filters shall meet the requirements specified in Table 2. The property values (except for AOS) represent minimum average roll values (MARV) in the weakest principal direction. For survivability during installation, the geotextile shall meet the minimum requirements in AASHTO M 288 Class 2, and shall have a minimum mass per unit area of 270 g/m 2 (8 ounces per square yard).

TABLE 2. GEOTEXTILE PHYSICAL PROPERTIES

PROPERTY TEST REQUIREMENT TEST METHOD

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Grab Tensile, N 700 nonwoven ASTM D 4632 (lbs) (160 nonwoven) or KS K 0520 1100 woven (250 woven)

Apparent Opening 150 - 212 ASTM D 4751 Size (μm (U.S. Sieve)) (70 - 100) or KS K 0754

Permittivity, 0.5 ASTM D 4491 sec-1

2.4 SOILS AND AGGREGATES

All material placed as fill shall consist of material classified by ASTM D 2487 or KS F 2324 as GW, GP, GC, GM, SP, SM, SC, CL, ML, or SW. The material shall be free of ice; snow;

frozen earth; trash; debris; sod; roots; organic matter; contamination from hazardous, toxic or radiological substances; or stones larger than 3 inches in any dimension. Each material shall be obtained entirely from one borrow source, unless the Contracting Officer determines that quality control is adequate and the alternate source produces material that is similar in gradation, texture, and interaction with the reinforcement.

Supply any testing required by the Contracting Officer to evaluate alternate sources. All materials shall be of a character and quality satisfactory for the purpose intended.

a. Drainage Aggregate shall meet the requirements of ASTM D 448, size No.7.

b. Aggregate Base material for the wall leveling pads shall meet the requirements of ASTM D 1241, gradation C.

c. Reinforced Fill. Soil placed in the reinforced fill zone shall consist of granular material with less than 5 percent passing the 75 μm (No. 200) sieve.

d. Retained Fill. Soil placed in the retained fill zone shall meet the minimum requirements above.

2.5 MASONRY ADHESIVE

The masonry adhesive shall meet the following requirements:

a. ASTM C 920, Type S, Grade NS, Class 25

b. expected 30 year life

c. meet the recommendations of the block manufacturer

2.6 DRAINAGE PIPE

The drainage pipe shall be corrugated polyethylene pipe meeting requirements of AASHTO M 252.

PART 3 EXECUTION

3.1 CLASSIFICATION OF SOIL MATERIALS

Perform classification of soil materials in accordance with ASTM D 2488. The Contracting Officer reserves the right to revise the Contractor classifications. In the case of disagreement, the Contracting Officer's classification will govern unless the soils are classified in accordance with ASTM D 2487 or KS F 2324. All testing completed by the Contractor in conjunction with soil material classification will be considered incidental to the contract work.

3.2 EARTHWORK

The leveling pad and reinforced fill zone shall bear on undisturbed native soils, or acceptably placed and compacted fill. In the event that it is necessary to remove material to a depth greater than specified or to place fill below the leveling pad not otherwise provided for in the contract, the Contracting Officer shall be notified prior to work and an adjustment in the contract price will be considered in accordance with the contract.

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Additional work not authorized by the Contracting Officer shall be at the Contractor's expense.

3.2.1 Excavation

Foundation soil shall be excavated as required for leveling pad dimensions and reinforcement placement shown on the construction drawings. Material for backfilling shall be stockpiled in a neat and orderly manner at a sufficient distance from the banks of the excavation to avoid overloading and to prevent slides or caving. Excavation and fill shall be performed in a manner and sequence that will provide proper drainage at all times.