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HomeMy WebLinkAboutSDP201800050 Other 2018-09-12Albemarle County, Virginia NOTES: 1. A QUALIFIED TESIFING AGENCY SHALL EVALUATE THE FOUNDATION SOILS PRIOR TO AND DURING CONSTRUCTION. UNSUITABLE SOILS SHALL BE REMOVED AND REPLACED WITH PROPERLY COMPACTED FILL AS RECOMMENDED BY THE OWNER'S GEOTECHNICAL ENGINEER. UNSUITABLE SOILS ARE DEFINED AS ANY SOILS THAT DO NOT HAVE SUFFICIENT BEARING CAPACITY OR WILL CAUSE EXCESSIVE WALL SETTLEMENT. 2. SOILS USED IN THE REINFORCED ZONE SHALL NOT HAVE A PLASTICITY INDEX (PI) GREATER THAN 20, A LIQUID LIMIT (LL) GREATER THAN 45, AND NO MORE THAN 45% IFINES (-200 SIEVE). OTHER MATERIALS SHALL REQUIRE APPROVAL BY THE WALL DESIGNER. 3. NOTE:PARAMETE:RS BELOW TO BE VERIFIED DURING CONSTRUCTION BY DEA. 7. QUALITY CONTROL AND QUALITY ASSURANCE TESTING SHALL BE PERFORMED ON A FULL-TIME BASIS BY A QUALIFIED TESTING AGENCY. THE SOILS AND MATERIALS PLACED IN THE REINFORCED ZONE SHALL BE IN ACCORDANCE WITH THE SPECIFICATIONS SHOWN IN THESE WALL DESIGN DRAWINGS. DOCUMENTATION SHALL INCLUDE FIELD DENSITY TEST RESULTS, FILL TYPE, LIFT THICKNESS, SOILS LABORATORY BULK SAMPLE TEST RESULTS (GRAIN SIZE, COMPACTION, ATTERBERG LIMITS, ETC) , AND GEOGRID TYPE, LENGTH AND PLACEMENT ELEVATION. DENSITY TESTING OF SOILS USED IN REINFORCED ZONE IS NOT REQUIRED IF VDOT NO. 57 STONE IS USED FOR REINFORCED ZONE FILL. 8. COMPACT FILL TO 95% OF THE SOIL'S STANDARD PROCTOR DENSITY (ASTM D6918) FOR THE ENTIRE WALL HEIGHT AT A MOISTURE CONTENT PRIOR TO COMPACTION WITHIN 3% OF THE SOIL'S OPTIMUM MOISTURE CONTENT. IF VDOT NO. 57 STONE IS USED IN THE REINFORCED ZONE, PLACE NO. 57 STONE IN LAYERS NO GREATER THAN 12 INCHES AND COMPACT WITH A MINIMUM OF 4 PASSES WITH A VIBRATORY COMPACTOR. COMPACTION WITHIN 4 FEET OF BACK OF BLOCK SHALL BE PERFORMED WITH LIGHTWEIGHT HAND -OPERATED EQUIPMENT AND IN THINNER LIFTS. REINFORCED SOIIL: 28 DEGREES, MOIST UNIT WEIGHT = 125 pcf. 9. INSTALL ALL WALL COMPONENTS AND MATERIALS IN ACCORDANCE WITH MANUIFACTURER'S INSTALLATION PROCEDURES AND RECOMMENDATIONS. RETAINED SOIL: :28 DEGREES, MOIST UNIT WEIGHT = 125 pcf. RETAINED FILL: 318 DEGREES, MOIST UNIT WEIGHT = 125 pcf. 10. GUARDRAIL AND/OR FENCE SHALL BE IN COMPLIANCE WITH LOCAL BUILDING C(ODE, STATEWIDE BUILDING CODE, OSHA REQUIREMENTS AND OTHER FOUNDATION SOIILS: 28 DEGREES, MOIST UNIT WEIGHT = 125 pcf. APPLICABLE AGENCY REQUIREMENTS. COMPLIANCE WITH CODE IS RESPONSIBILITY OF OWNER. DRAINAGE/LEVELING PAD STONE: 38 DEGREES, MOIST UNIT WEIGHT = 115/135 pcf. 4. NO SUBSTITUTIOINS OF THE MATERIALS SHOWN ON THESE DRAWINGS SHALL BE PERMITTED UNLESS APPROVED BY DEA. 5. WALL ALIGNMENT' AND GRADE SHALL BE BASED ON SURVEY CONTROL BY OTHERS. ALIGNMENT AND GRADE ARE BASED ON THE GRADING PLAN BY BOHLER ENGIISVEERING, DATED 08/16/18. 6. ANY ALIGNMENT OR GRADE CHANGES MADE IN THE FIELD OR PROPOSED BY THE OWNER'S CIVIL DESIGNER, OR THE CONTRACTOR SHALL BE IMMEDIATELY REPORTED TO DEA SO THAT EVALUATION AND EFFECT ON DESIGN CHANGES, IF NECESSARY, CAN BE MADE BY DEA. 11. A PRECONSTRUCTION MEETING SHOULD BE HELD PRIOR TO ANY WALL CONSTRUCTION. ATTENDEES SHOULD INCLUDE OWNER, WALL DESIGN ENGINEER, WALL CONTRACTOR, SURVEYOR, AND EARTHWORK CONTRACTOR. 12. WALL CONTRACTOR SHALL PROVIDE CERTIFICATION LETTER TO OWNER WITHIN ONE WEEK OF WALL COMPLETION STATING THAT THE WALL WAS CONSTRUCTED IN ACCORDANCE WITH THE APPROVED PLANS AND SPECIFICATIIONS. WALL SHALL BE CONSIDERED COMPLETE FOR PURPOSES OF THESE PLANS WHEN CAP BLOCKS HAVE BEEN INSTALLED AND SITE GRADING BEHIND AND AT TOP OF WALL HAS BEEN COMPLETED. WARRANTY FOR THE WALL SHALL BE AS AGREED UPON WITH THE OWNER AND STATED IN THE W)ALL BUILDER'S CONTRACT. DOMINION ENGINEERING ASSOCIATES. INC. 8511 INDIAN HILLS COURT, SUITE 202 FREDERICKSBURG, VA 22407 (540) 710-9339 %J w L I r% f; A �i V / v J -T v L 1 v 1 0 r v L I FEES n 0 / v 0 1 v 9. 1 v v L I 8 7 6 A 0 3 1 CONCRETE SEGMENTAL RETAINING WALL SYSTEM H PART 1 - GENERAL 1.01 SECTION INCLUDES A. RETAINING WALL SYSTEM CONSTRUCTED OF CONCRETE SEGMENTAL RETAINING WALL UNITS. B. GEOSYNTHETIC REINFORCEMENT AND GEOTEXTILE FABRIC C. LEVELING PAD BASE D. DRAINAGE AGGREGATE E. BACKFILL F. DRAINAGE PIPE G. ADHESIVES 1.02 REFERENCES A. AMERICAN ASSOCIATION OF STATE HIGHWAY TRANSPORTATION OFFICIALS (AASHTO) 1. AASHTO M288 GEOTEXTILE SPECIFICATION FOR HIGHWAY APPLICATIONS 2. AASHTO STANDARD SPECIFICATIONS FOR HIGHWAY BRIDGES G B. AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) 1. ASTM C140 STANDARD TEST METHODS FOR SAMPLING AND TESTING CONCRETE MASONRY UNITS AND RELATED UNITS 2. ASTM C1262 STANDARD TEST METHOD FOR EVALUATING THE FREEZE -THAW DURABIILITY OF MANUFACTURED CONCRETE MASONRY UNITS AND RELATED CONCRETE UNITS 3. ASTM C1372 STANDARD SPECIFICATION FOR SEGMENTAL RETAINING WALL UNITS 4. ASTM D448 STANDARD CLASSIFICATION FOR SIZES OF AGGREGATE FOR ROAD AND BRIDGE CONSTRUCTION 5. ASTM D698 STANDARD TEST METHODS FOR LABORATORY COMPACTION CHARACTERISTICS OF SOIL USING STANDARD EFFORT (12,400 FT-LBF/F3) (600 KN-M/M3) 6. ASTM D1556 STANDARD TEST METHOD FOR DENSITY AND UNIT WEIGHT OF SOIL IN PLACE BY THE SAND CONE METHOD 7. ASTM D1557 STANDARD TEST METHODS FOR LABORATORY COMPACTION CHARACTERISTICS OF SOIL USING MODIFIED EFFORT (56,000 FT-LBF/F3) (2700 KN-M/M3) 8. ASTM D2487 STANDARD CLASSIFICATION OF SOILS FOR ENGINEERING PURPOSES (UNIFIED SOIL CLASSIFICATION SYSTEM) 9. ASTM D2922 STANDARD TEST METHODS FOR DENSITY OF SOIL AND SOIL -AGGREGATE IN PLACE BY NUCLEAR METHODS (SHALLOW DEPTH) 10. ASTM D3034 STANDARD SPECIFICATION FOR TYPE PSM POLY VINYL CHLORIDE (PVC)) SEWER PIPE AND FITTINGS 11. ASTM D4318 STANDARD TEST METHODS FOR LIQUID LIMIT, PLASTIC LIMIT, AND PLASTICITY INDEX OF SOILS 12. ASTM D4595 STANDARD TEST METHOD FOR TENSILE PROPERTIES OF GEOTEXTILES BY THE WIDE -WIDTH STRIP METHOD 13. ASTM D5262 STANDARD TEST METHOD FOR EVALUATING THE UNCONFINED TENSION CREEP BEHAVIOR OF GEOSYNTHETICS 14. ASTM F405 STANDARD SPECIFICATION FOR CORRUGATED POLYETHYLENE (PE) TUBIINGS AND FITTINGS F 15. ASTM G51 STANDARD TEST METHOD FOR MEASURING PH OF SOIL FOR USE IN CORROSION TESTING C. NATIONAL CONCRETE MASONRY ASSOCIATION (NCMA) 1. NCMA DESIGN MANUAL FOR SEGMENTAL RETAINING WALLS, SECOND EDITION, SECOND PRINTING (1997) 2. NCMA SRWU-1 DETERMINATION OF CONNECTION STRENGTH BETWEEN GEOSYNTHETICS AND SEGMENTAL CONCRETE UNITS 3. NCMA SRWU-2 DETERMINATION OF SHEAR STRENGTH BETWEEN SEGMENTAL CONCRETE UNITS 1.03 DEFINITIONS A. REINFORCED FILL: SOIL WHICH IS USED AS FILL BEHIND THE DRAINAGE AGGREGATE AND WITHIN THE REINFORCED SOIL MASS. B. RETAINED SOIL: SOIL LOCATED IN THE AREA BEHIND THE REINFORCED ZONE. C. DRAINAGE AGGREGATE: MATERIAL USED WITHIN (IF APPLICABLE), BETWEEN, AND DIRECTLY BEHIND THE CONCRETE RETAINING WALL UNITS. D. FILTER FABRIC: MATERIAL USED FOR SEPARATION AND FILTRATION OF DISSIMILAR SOIL TYPES. E. FOUNDATION SOIL: SOIL MASS SUPPORTING THE LEVELING PAD AND REINFORCED SOIL Z'.ONE OF THE RETAINING WALL SYSTEM. F. IMPERVIOUS FILL: SOIL PLACED AT THE GROUND SURFACE THAT REDUCES/IMPEDES THE (FLOW OF WATER INTO THE REINFORCED ZONE. G. GEOSYNTHETIC REINFORCEMENT: MATERIAL SPECIFICALLY FABRICATED FOR USE AS A SOIL REINFORCEMENT. H. GLOBAL STABILITY : THE GENERAL MASS MOVEMENT OF A SOIL REINFORCED SEGMENTAL RETAINING WALL STRUCTURE AND ADJACENT SOIL MASS, STABILITY ANALYSIS TO BE PERFORMED BY GEOTECHNICAL ENGINEER. I. PROJECT ENGINEER: GEOTECHNICAL ENGINEER SHALL BE EMPLOYED TO PERFORM SITE (OBSERVATIONS, PROVIDE RECOMMENDATIONS FOR FOUNDATION SUPPORT, AND EVALUATE SOIL SHEAR STRENGTH PARAMETERS ON A FULL-TIME BASIS. 1.04 SUBMITTALS TO OWNER A. TEST REPORTS: INDEPENDENT LABORATORY REPORTS STATING MOISTURE ABSORPTION AND COMPRESSIVE STRENGTH PROPERTIES OF THE CONCRETE RETAINING WALL UNITS MEET THE PROJECT SPECIFICATIONS WHEN TESTED IN ACCORDANCE WITH ASTM C140. 1.05 DELIVERY, STORAGE AND HANDLING A. DELIVER, STORE, AND HANDLE MATERIALS IN ACCORDANCE WITH MANUFACTURER'S RECOMMENDATIONS, IN SUCH A MANNER AS TO PREVENT DAMAGE. CHECK THE MATERIALS UPON DELIVERY TO ASSURE THAT PROPER MATERIAL HAS BEEN RECEIVED. STORE ABOVE GROUND ON WOOD PALLETS OR BLOCKING. REMOVE DAMAGED OR OTHERWISE UNSUITABLE MATERIAL, WHEN SO DETERMINED, FROM THE SITE. 1. EXPOSED FACES OF CONCRETE WALL UNITS SHALL BE FREE OF CHIPS, CRACKS, STAINS, AND OTHER IMPERFECTIONS DETRACTING FROM THEIR APPEARANCE, WHEN VIEWED FROM A DISTANCE OF 10 FEET. 2, PREVENT MUD, WET CEMENT, ADHESIVES AND SIMILAR MATERIALS WHICH MAY HARM APPEARANCE OF UNITS, FROM COMING IN CONTACT WITH SYSTEM COMPONENTS. 1.06 EXTRA MATERIALS D A. FURNISH OWNER WITH REPLACEMENT UNITS IDENTICAL TO THOSE INSTALLED ON THE PROJECT, AS MAYBE REQUESTED BY OWNER. PART 2-PRODUCTS 2.01 MATERIALS A. CONCRETE DIAMOND PRO RETAINING WALL UNITS:: 1. PHYSICAL REQUIREMENTS a. MEET REQUIREMENTS OF ASTM C1372, EXCEPT THE MAXIMUM WATER ABSORPTION SHALL BE LIMITED TO 7 PERCENT, AND UNIT HEIGHT DIMENSIONS SHALL NOT VARY MORE THAN PLUS OR MINUS 1/16 INCH FRROM THAT SPECIFIED IN THE ASTM REFERENCE, NOT INCLUDING TEXTURED FACE. b. UNIT FACE AREA: NOT LESS THAN 1.0 SQUARE FEET. C. COLOR: FROM MANUFACTURER TO MATCH COLOR OF EXISTING WALL BLOCKS. d. FACE PATTERN GEOMETRY: SELECTED BY OWNER. e. TEXTURE: AS SELECTED BY OWNER. B. GEOSYNTHETIC REINFORCEMENT: SHALL BE AS SHOWN ON THE PROFILE FOR EACH RETAINING WALL. C. LEVELING PAD BASE: CRUSHED STONE MEETING THE REQUIREMENTS OF VDOT No. 21A OfR VDOT No. 216; MINIMUM THICKNESS OF 8 INCHES. D. DRAINAGE AGGREGATE: VDOT No. 57 STONE. C E. REINFORCED FILL: MATERIAL PLACED ABOVE AND BELOW GEOGRID REINFORCEMENT WITH PROPERTIES SHOWN IN GENERAL NOTES ON COVER SHEET. F. IMPERVIOUS MATERIAL: CLAYEY SOIL OR OTHER SIMILAR MATERIAL WHICH WILL IMPEDE PERCOLATION INTO THE DRAINAGE ZONE BEHIND THE WALL. G. DRAINAGE PIPE: PERFORATED (BEHIND WALL) OR SOLID (THROUGH WALL) PVC OR CORRUGATED HDPE PIPE MANUFACTURED IN ACCORDANCE WITH D3034 AND/OR ASTM F405. H. CONSTRUCTION ADHESIVE: EXTERIOR GRADE ADHESIVE AS RECOMMENDED BY THE RETAIINING WALL UNIT MANUFACTURER. PART 3 - EXECUTION 3.01 EVALUATION A. EVALUATION SHOULD BE CONDUCTED BY THE OWNER OR OWNER'S DESIGNATED REPRESENTATIVE. B. PRIOR TO WALL CONSTRUCTION, GEOTECHNICAL ENGINEER SHALL PERFORM GLOBAL STABILITY ANALYSIS BASED ON GEOTECHNICAL SOIL BORINGS WITHIN AND ADJACENT TO THE WALL FOOTPRINT. C. EVALUATE THE AREAS AND CONDITIONS UNDER WHICH THE RETAINING WALL SYSTEM IS TO BE ERECTED, AND NOTIFY THE CONTRACTOR IN WRITING OF CONDITIONS DETRIMENTAL TO THE PROPER AND TIMELY COMPLETION OF THE WORK;. DO NOT PROCEED WITH THE WORK UNTIL UNSATISFACTORY CONDITIONS HAVE BEEN CORRECTED. WALL CONTRACTOR SHALL VISIT THE SITE TO PERFORM SAME EVALUATION. D. PROMPTLY NOTIFY THE WALL DESIGN ENGINEER OF SITE CONDITIONS WHICH MAY AFFECT WALL PERFORMANCE, SOIL CONDITIONS OBSERVED OTHER THAN THOSE ASSUMED, OR OTHER CONDITIONS THAT MAY REQUIRE A REEVALUATION OiF THE WALL DESIGN. E. VERIFY THE LOCATION OF EXISTING STRUCTURES AND UTILITIES PRIOR TO EXCAVATION. 3.02 PREPARATION A. ENSURE SURROUNDING STRUCTURES ARE PROTECTED FROM THE EFFECTS OF WALL EXCAVATION. B. EXCAVATION SUPPORT, IF REQUIRED, IS THE RESPONSIBILITY OF THE CONTRACTOR, INCLUDING THE STABILITY OF THE EXCAVATION AND IT'S INFLUENCE ON ADJACENT PROPERTIES AND STRUCTURES. C. OWNER OR OWNER'S REPRESENTATIVE SHALL BE RESPONSIBLE FOR LOCATING ANY AND ALL UTILITIES IN THE WORK AREA PRIOR TO WALL CONSTRUCTION. UTILITY LOCATIONS SHALL BE IDENTIFIED IN THE FIELD AND SHOWN TO THE WALL CONTRACTOR'S SITE FOREMAN. 3.03 EXCAVATION A. EXCAVATE TO THE LINES AND GRADES SHOWN ON THE DRAWINGS. OVER -EXCAVATION SHOULD BE EVALUATED BY GEOTECHNICAL ENGINEER. REPLACEMENT OF OVEREXCAVATED SOILS WITH COMPACTED FILL SHALL BE AS RECOMMENDED BY GEOTECHNICAL ENGINEER. USE CARE IN EXCAVATING TO PREVENT DISTURBANCE OF THE BASE BEYOND THE LINES SHOWN. 3.04 FOUNDATION PREPARATION A. EXCAVATE FOUNDATION SOIL AS REQUIRED FOR FOOTING OR BASE DIMENSION SHOWN ON THE DRAWINGS, AND AS RECOMMENDED BY DEA. B. DEA SHALL EVALUATE FOUNDATION SOIL TO ENSURE THAT THE ACTUAL FOUNDATION SOIL STRENGTH MEETS OR EXCEEDS THAT INDICATED ON THE DRAWINGS. REMOVE SOIL NOT MEETING THE REQUIRED STRENGTH. OVERSIZE RESULTING SPACE SUFFICIENTLY FROM THE FRONT OF THE BLOCK TO THE BACK OF THE REINFORCEMENT, AND BACKFILL WITH SUITABLE COMPACTED BACKFILL SOILS. C. DEA SHALL EVALUATE WHETHER THE FOUNDATION SOILS WILL REQUIRE SPECIAL TREATMENT OR CORRECTION TO REDUCE TOTAL AND DIFFERENTIAL SETTLEMENT, D. FILL OVER -EXCAVATED AREAS WITH SUITABLE COMPACTED BACKFILL, AS RECOMMENDED BY DEA. 3.05 BASE COURSE PREPARATION A. PLACE BASE MATERIALS TO THE DEPTHS AND WIDTHS SHOWN ON THE DRAWINGS, UPON UNDISTURBED SOILS, OR FOUNDATION SOILS PREPARED IN ACCORDANCE WITH ARTICLE 3.04. 1. EXTEND THE LEVELING PAD LATERALLY AT LEAST 6 INCHES IN FRONT AND BEHIND THE LOWERMOST CONCRETE RETAINING WALL UNIT. 2. PROVIDE AGGREGATE BASE COMPACTED TO 8 INCHES THICK (MINIMUM). B. COMPACT AGGREGATE BASE MATERIAL TO PROVIDE A LEVEL, HARD SURFACE ON WHICH TO PLACE THE FIRST COURSE OF UNITS. C. PREPARE BASE MATERIALS TO ENSURE COMPLETE CONTACT WITH RETAINING WALL UNITS. GAPS ARE NOT ALLOWED. 3.06 ERECTION 3.10 FIELD QUALITY CONTROL A. INSTALLER IS RESPONSIBLE FOR PROPER INSTALLATION OF SYSTEM COMPONENTS. B. OWNER SHALL ENGAGE DEA TO VERIFY THE CORRECT INSTALLATION OF SYSTEM COMPONENTS IN ACCORDANCE WITH THESE SPECIFICATIONS AND THE DRAWINGS. C. CORRECT ANY WORK WHICH DOES NOT MEET THESE SPECIFICATIONS OR THE REQUIREMENTS SHOWN ON THE WALL DESIGN DRAWINGS. D. TESTING AGENCY TO PERFORM COMPACTION TESTING OF THE FILL PLACED AND COMPACTED IN THE FOUNDATION, RETAINED, AND REINFORCED FILL ZONES. 1. TESTING FREQUENCY a. MINIMUM ONE TEST FOR EVERY BLOCK COURSE (VERTICAL) OF FILL PLACED AND COMPACTED, FOR EVERY 50 LINEAL FEET OF RETAINING WALL. b. VARY COMPACTION TEST LOCATIONS TO COVER THE ENTIRE AREA OF THE REINFORCED SOIL ZONE, INCLUDING THE AREA COMPACTED BY THE HAND -OPERATED COMPACTION EQUIPMENT. IF OPEN GRADED STONE (SUCH AS VDOT No. 57 STONE) IS USED AS MATERIAL IN REINFORCED ZONE, STONE SHALL BE COMPACTED BY MINIMUM FOUR PASSES WITH VIBRATORY COMPACTION EQUIPMENT. 3.11 ADJUSTING AND CLEANING A. REPLACE DAMAGED UNITS WITH NEW UNITS AS THE WORK PROGRESSES. B. REMOVE DEBRIS GENERATED BY WALL CONTRACTOR AND LEAVE ADJACENT AREAS CLEAN. A. GENERAL: ERECT UNITS IN ACCORDANCE WITH MANUFACTURER'S INSTRUCTIONS AND RECOMMENDATIONS, AND AS SPECIFIED HEREIN. 3.12 MEASUREMENT, PAYMENT AND CERTIFICATION B. PLACE FIRST COURSE OF CONCRETE WALL UNITS ON THE PREPARED BASE MATERIAL. CHECK UNITS FOR LEVEL AND ALIGNMENT. MAINTAIN THE SAME ELEVATION AT THE TOP OF EACH UNIT WITHIN EACH SECTION OF THE BASE COURSE. A. MEASUREMENT OF SEGMENTAL RETAINING WALL SHALL BE ON AN INSTALLED SQUARE FOOT BASIS COMPUTED ON THE TOTAL FACE AREA OF C. ENSURE THAT FOUNDATION UNITS ARE IN FULL CONTACT WITH NATURAL OR COMPACTED SOIL BASE. WALL INSTALLED. WALL FACE AREA INCLUDES THE BOTTOM OF THE BASE COURSE TO THE TOP OF THE WALL, AND THE ENTIRE LENGTH OF THE D. PLACE CONCRETE WALL UNITS SIDE -BY -SIDE FOR FULL LENGTH OF WALL ALIGNMENT. ALIGNMENT MAY BE DONE BY USING A STRING LINE MEASURED WALL. FROM THE BACK OF THE BLOCK. GAPS ARE NOT ALLOWED BETWEEN THE FOUNDATION CONCRETE WALL UNITS. B. PAYMENT SHALL BE IN ACCORDANCE WITH WALL INSTALLER'S CONTRACT. E. PLACE 24 INCHES (MINIMUM) OF DRAINAGE AGGREGATE BETWEEN, AND DIRECTLY BEHIND THE CONCRETE WALL UNITS. FILL VOIDS IN RETAINING WALL C. WALL CONTRACTOR SHALL PROVIDE CERTIFICATE LETTER WITHIN ONE WEEK OF WALL COMPLETION STATING THAT THE WALL WAS UNITS WITH DRAINAGE AGGREGATE. PROVIDE A DRAINAGE ZONE BEHIND THE WALL UNITS TO 9 INCHES BELOW THE FINAL SURFACE GRADE IN ORDER TO CAP THE BACKFILL CONSTRUCTED IN ACCORDANCE WITH THE APPROVED PLANS AND SPECIFICATIONS. WARRANTY FOR THE WALL SHALL BE AS AGREED UPON AND DRAINAGE AGGREGATE ZONE WITH 9 INCHES OF IMPERVIOUS MATERIAL. WITH THE OWNER AND STATED IN THE WALL BUILDER'S CONTRACT. F. INSTALL DRAINAGE PIPE AT THE LOWEST ELEVATION POSSIBLE (SEE DETAILS SHEET), TO MAINTAIN GRAVITY FLOW OF WATER TO OUTSIDE OF THE REINFORCED ZONE. SLOPE THE MAIN COLLECTION DRAINAGE PIPE, LOCATED JUST BEHIND THE CONCRETE RETAINING WALL UNITS, 2 PERCENT (MINIMUM) TO PROVIDE GRAVITY FLOW TO THE DAYLIGHTED AREAS. DAYLIGHT THE MAIN COLLECTION DRAINAGE PIPE TO AN APPROPRIATE LOCATION AWAY FROM THE WALL SYSTEM AT EACH LOW END OF SPECIFICATIONS POINT. G. REMOVE EXCESS FILL FROM TOP OF UNITS AND INSTALL NEXT COURSE. DRAINAGE AGGREGATE AND BACKFILL ARE TO BE COMPACTED BEFORE INSTALLATION OF NEXT COURSE. H. CHECK EACH COURSE FOR LEVEL AND ALIGNMENT. I. INSTALL EACH SUCCEEDING COURSE. BACKFILL AS EACH COURSE IS COMPLETED. PULL THE UNITS FORWARD UNTIL THE LOCATING SURFACE OF THE UNIT CONTACTS THE LOCATING SURFACE OF THE UNITS IN THE PRECEDING COURSE. INTERLOCK WALL SEGMENTS THAT MEET AT CORNERS BY OVERLAPPING SUCCESSIVE COURSES. AT -EACH CONCRETE RETAINING WALL UNITS AT EXTERIOR CORNERS WITH ADHESIVE SPECIFIED. J. INSTALL GEOSYNTHETIC REINFORCEMENT IIN ACCORDANCE WITH GEOSYNTHETIC MANUFACTURER'S RECOMMENDATIONS AND THE WALL DESIGN DRAWINGS. 1. ORIENT GEOSYNTHETIC REINFORCEMENT WITH THE HIGHEST STRENGTH AXIS PERPENDICULAR TO THE WALL FACE. 2. PRIOR TO GEOSYNTHETIC REINFORCEMENT PLACEMENT, PLACE THE BACKFILL AND COMPACT TO THE ELEVATION OF THE TOP OF THE WALL UNITS AT THE ELEVATION OF THE GEOSYNTHETIC REINFORCEMENT. 3. PLACE GEOSYNTHETIC REINFORCEMENT AT THE ELEVATIONS AND TO THE LENGTHS SHOWN ON THESE DESIGN DRAWINGS. 4. LAY GEOSYNTHETIC REINFORCEMENT HORIZONTALLY ON TOP OF THE CONCRETE RETAINING WALL UNITS AND THE COMPACTED BACKFILL SOILS. PLACE THE GEOSYNTHETIC REINFORCEMENT WITHIN ONE INCH OF THE FACE OF THE CONCRETE RETAINING WALL UNITS. PLACE THE NEXT COURSE OF CONCRETE RETAINING WALL UNITS ON TOP OF THIE GEOSYNTHETIC REINFORCEMENT. 5. THE GEOSYNTHETIC REINFORCEMENT SHALL BE IN TENSION AND FREE FROM WRINKLES PRIOR TO PLACEMENT OF THE REINFORCED FILL SOILS. PULL GEOSYNTHETIC REINFORCEMENT HAND -TAUT AND SECURE IN PLACE WITH STAPLES, STAKES, OR BY HAND -TENSIONING UNTIL THE GEOSYNTHETIC REINFORCEMENT IS COVERED BY 6 IN(CHES OF LOOSE FILL. 6. THE GEOSYNTHETIC REINFORCEMENTS SHALL BE CONTINUOUS THROUGHOUT THEIR EMBEDMENT LENGTHS. SPLICES IN THE GEOSYNTHETIC REINFORCEMENT STRENGTH DIRECTION ARE NOT ALLOWED. 7. WHERE PIPES INTERFERE WITH GRID LOCATIONS/ELEVATIONS SHOWN ON PLANS, GRID SHALL BE PLACED ALONG SIDE OF, UNDER, AND/OR ABOVE TO MATCH ELEVATIONS ON OTHER SIDE OF PIPE AS SHOWN. ADDITIONAL GRID MAY BE REQUIRED BY WALL DESIGNER ABOVE AND BELOW PIPE, DEPENDING ON ALIGNMENT ANGLE AND SLOPE OF PIPE. 8. DO NOT OPERATE TRACKED CONSTRUCTION EQUIPMENT DIRECTLY ON THE GEOSYNTHETIC REINFORCEMENT. AT LEAST 6 INCHES OF COMPACTED BACKFILL SOIL IS REQUIRED PRIOR TO) OPERATION OF TRACKED VEHICLES OVER THE GEOSYNTHETIC REINFORCEMENT. KEEP TURNING OF TRACKED CONSTRUCTION EQUIPMENT TO A MINIMUM. 9. RUBBER -TIRED EQUIPMENT MAY PASS OVER THE GEOSYNTHETIC REINFORCEMENT AT SPEEDS OF LESS THAN 5 MILES PER HOUR. TURNING OF RUBBER -TIRED EQUIPMENT IS NOT ALLOWED ON THE GEOSYNTHETIC REINFORCEMENT. K. USE SPECIAL CORNER BLOCKS AS RECOMMENDED BY THE BLOCK MANUFACTURER, L. THE CONTRACTOR SHALL START AND FINISH WALL CONSTRUCTION WITHOUT UNDUE DELAY. IF CONTRACTOR IS INSTRUCTED BY OWNER TO STOP WORK BEFORE COMPLETE INSTALLATION OR IF WALL CONTRACTOR ELECTS TO DELAY WORK FOR ANY REASON, A CAPPING LAYER OF LOW PERMEABILITY SOIL SHALL BE PLACED OVER TOP OF THE DRAINAGE STONE AT LEAST 8 INCHES THICK AND COMPACTED A MINIMUM OF FOUR PASSES WITH A VIBRATORY PLATE COMPACTOR. THIS LAYER IS CONSIDERED TEMPORARY, AND SHALL BE COMPLETELY REMOVED PRIOR TO RESUMING WALL CONSTRUCTION. M. WALL CONTRACTOR SHALL COORDINATE WITH GENERAL CONTRACTOR/OWNER THE FINAL PLACEMENT OF IMPERVIOUS FILL OVER THE DRAINAGE LAYER BEHIND THE WALL. THE IMPERVIOUS FILL IS CONSIDERED PART OF THIS WALL SYSTEM AND SHOULD BE PLACED PRIOR TO WALL CONTRACTOR'S DEMOBILIZATION. 3.07 REINFORCED FILL PLACEMENT A. PLACE FILL IN THE REINFORCED ZONE, SPREAD AND COMPACT IN A MANNER THAT WILL MINIMIZE SLACK IN THE GEOSYNTHETIC REINFORCEMENT. B. ONLY LIGHTWEIGHT HAND -OPERATED COMPACTION EQUIPMENT IS ALLOWED WITHIN 4 FEET OF THE BACK OF THE RETAINING WALL UNITS. IF THE SPECIFIED COMPACTION CANNOT BE ACHIEVED WITHIN 4 FEET OF THE BACK OF THE RETAINING WALL UNITS, REPLACE THE REINFORCED SOIL IN THIS ZONE WITH DRAINAGE AGGREGATE MATERIAL AND COMPACT WITH A MINIMUM 4 PASSES WITH A LIGHT VIBRATORY COMPACTOR AND IN THIN LIFTS. C. MINIMUM COMPACTION REQUIREMENTS FOR FILL PLACED IN THE REINFORCED ZONE. 1. PLACE MATERIALS FOR USE IN THE REINFORCED ZONE IN LOOSE LAYERS NO GREATER THAN 8 INCHES FOR SOIL AND NO GREATER THAN 10 INCHES FOR CRUSHED STONE MATERIALS. 2. COMPACTION WITHIN 4 FEET OF THE BACK OF THE SEGMENTAL WALL UNITS SHALL BE PERFORMED WITH LIGHTWEIGHT, HAND -OPERATED COMPACTION EQUIPMENT AND IN THINNER LIFTS IF NECESSARY TO ACHIEVE COMPACTION THROUGHOUT ENTIRE LIFT. 3. COMPACT FILL (REINFORCED AND RETAINED) TO 95 PERCENT OF THE SOIL'S STANDARD PROCTOR MAXIMUM DRY DENSITY (ASTM D698) FOR THE ENTIRE WALL HEIGHT. WHERE WALL HEIGHTS ARE GREATER THAN 10 FT, COMPACT SOIL TO AT LEAST 98% OF SOIL'S STANDARD MAXIMUM DRY DENSITY (ASTM D-698) FOR FULL HEIGHT OF WALL. 4, UTILITY TRENCH BACKFILL: COMPACT UTILITY TRENCH BACKFILL IN OR BELOW THE REINFORCED ZONE TO 95 PERCENT OF THE SOIL'S STANDARD PROCTOR MAXIMUM DRY DENSITY (ASTM D698). 5. UTILITIES MUST BE PROPERLY DESIGNED (BY OTHERS) TO WITHSTAND ALL FORCES FROM THE RETAINING WALL UNITS, REINFORCED SOIL MASS, AND SURCHARGE LOADS, IF ANY. 6. WHERE CRUSHED ROCK (OPEN GRADED AGGREGATE SUCH AS VDOT No. 57 STONE) MATERIALS ARE USED IN THE REINFORCED ZONE, COMPACTION SHALL BE PERFORMED BY A MINIMUM OF 4 PASSES WITH A LIGHT VIBRATORY COMPACTOR AND IN THIN LIFTS. D. AT THE END OF EACH DAY'S OPERATION, SLOPE THE LAST LEVEL OF COMPACTED BACKFILL AWAY FROM THE INTERIOR (CONCEALED) FACE OF THE WALL TO DIRECT SURFACE WATER RUNOFF AWAY FROM THE WALL FACE. E. THE WALL AND EARTHWORK CONTRACTORS ARE RESPONSIBLE FOR ENSURING THAT THE FINISHED SITE DRAINAGE IS DIRECTED AWAY FROM THE RETAINING WALL SYSTEM. IN ADDITION, THE CONTRACTORS ARE RESPONSIBLE FOR ENSURING THAT SURFACE WATER RUNOFF FROM ADJACENT CONSTRUCTION AREAS IS NOT ALLOWED TO ENTER THE RETAINING WALL AREA OF THE CONSTRUCTION SITE. 3.08 CAP UNIT INSTALLATION (IF REQUIRED) A. APPLY ADHESIVE RECOMMENDED BY THE BLOCK MANUFACTURER TO THE TOP SURFACE OF THE UNIT BELOW AND PLACE THE CAP UNIT INTO DESIRED POSITION. B. CUT CAP UNITS AS NECESSARY TO OBTAIN THE PROPER FIT. 3.09 SITE CONSTRUCTION TOLERANCES A. SITE CONSTRUCTION TOLERANCES 1. VERTICAL ALIGNMENT: PLUS OR MINUS 1-1/2 INCHES OVER ANY 10-FOOT DISTANCE, WITH A MAXIMUM DIFFERENTIAL OF 3 INCHES OVER THE LENGTH OF THE WALL. 2. HORIZONTAL LOCATION CONTROL FROM GRADING PLAN a. STRAIGHT LINES: PLUS OR MINUS 1-1/2 INCHES OVER ANY 10-FOOT DISTANCE. b. CORNER AND RADIUS LOCATIONS: PLUS OR MINUS 12 INCHES. C. CURVES AND SERPENTINE RADII: PLUS OR MINUS 2 FEET. B. AESTHETICS OF FINISHED WALL IS NOT RESPONSIBILITY OF WALL DESIGNER. r. d pia 026397 G nNAt. DOMINION ENGINEERING ASSOCIATES, INC. 8511 INDIAN HILLS COURT, SUITE 202 FREDERICKSBURG, VA 22407 (540)710-9339 BROOKHILL APARTMENTS SECTION 1 BLOCK 4A and 4B RETAINING WALL SPECIFICATIONS ALBEMARLE COUNTY, VIRGINIA SPECIFICATIONS SEPT. 12, 2018I SHEET: S7 OF 7 I SCALE NITS �I G L■ E L�J L 0 r2 0 2 1