USACE / NAVFAC / AFCESA / NASA UFGS-31 60 00 (November 2008) ----------------------------- Preparing Activity: USACE (CW) Superseding UFGS-31 60 00 (April 2006) UNIFIED FACILITIES GUIDE SPECIFICATIONS References are in agreement with UMRL dated January 2009 SECTION 31 60 00 FOUNDATION PREPARATION 11/08 NOTE: This guide specification covers the requirements for embankments and concrete structures placed on rock foundations, including all operations on the rock surface to make that surface acceptable for the placement of embankment or concrete. Edit this guide specification for project specific requirements by adding, deleting, or revising text. For bracketed items, choose applicable items(s) or insert appropriate information. Remove information and requirements not required in respective project, whether or not brackets are present. Comments and suggestions on this guide specification are welcome and should be directed to the technical proponent of the specification. A listing of technical proponents, including their organization designation and telephone number, is on the Internet. Recommended changes to a UFGS should be submitted as a Criteria Change Request (CCR). PART 1 GENERAL NOTE: This section is not complete, but should normally be incorporated into the sections dealing with EARTHWORK, and/or CONCRETE, or a separate section on FOUNDATION PREPARATION may be included in the project specifications. 1.1 UNIT PRICES NOTE: If Section 01 22 00.00 10 MEASUREMENT AND PAYMENT is included in the project specifications, this paragraph title (UNIT PRICES) should be deleted from this section and the remaining appropriately edited subparagraphs below should be inserted into Section 01 22 00.00 10. 1.1.1 Preliminary Cleanup 1.1.1.1 Payment Payment will be made for costs for each preliminary cleanup satisfactorily performed at the direction of the Contracting Officer. Payment will be made for each cleanup of the same area if more than one cleanup has been directed and satisfactorily performed. 1.1.1.2 Measurement Preliminary cleanup will be measured for payment by determining the area cleaned to the nearest square meter yard. 1.1.1.3 Unit of Measure Unit of measure: square meter yard. 1.1.2 Final Cleanup 1.1.2.1 Payment Payment will be made for costs associated with final cleanup of the area [for each type of foundation preparation] that has been satisfactorily prepared. Where preliminary cleanup has been directed and performed and the Contractor subsequently performs final cleanup, payment will be made for preliminary cleanup. Payment will not be made for any cleanup subsequent to final cleanup. 1.1.2.2 Measurement Final cleanup will be measured for payment by determining the area cleaned to the nearest square meter yard. 1.1.2.3 Unit of measure Square meter yard. 1.1.3 Foundation Preparation 1.1.3.1 Payment Payment will be made for costs associated with foundation preparation of the area [for each type of foundation preparation] that has been satisfactorily prepared. Where preliminary cleanup has been directed and performed and the Contractor subsequently performs foundation preparation, payment will be made for foundation preparation. Payment will not be made for more than one foundation preparation of the same area. 1.1.3.2 Measurement Foundation preparation will be measured for payment by determining the area prepared to the nearest square meter yard. 1.1.3.3 Unit of measure Square meter yard. 1.1.4 Dental Concrete 1.1.4.1 Payment Payment will be made for costs associated with dental concrete placed. 1.1.4.2 Measurement Dental concrete will be measured for payment by determining the volume to the nearest one-tenth cubic meter yard . 1.1.4.3 Unit of measure Cubic meter yard. 1.1.5 Dental Mortar 1.1.5.1 Payment Payment will be made for costs associated with dental mortar placed. 1.1.5.2 Measurement Dental mortar will be measured for payment by determining the volume to the nearest one-tenth cubic meter yard . 1.1.5.3 Unit of measure Cubic meter yard. 1.1.6 [Shotcrete] 1.1.6.1 [Payment Payment will be made for costs associated with shotcrete satisfactorily placed.] 1.1.6.2 [Measurement Shotcrete will be measured for payment by determining the area satisfactorily covered to the nearest square meter yard.] 1.1.6.3 [Unit of measure Square meter yard.] 1.1.7 [Protective Coating] 1.1.7.1 [Payment Payment will be made for costs associated with protective coating satisfactorily applied. Separate payment will not be made for reapplication necessary due to damage by construction activities, fault or negligence of the Contractor, or failure of the Contractor to prosecute the work in a timely manner. Otherwise, separate payment shall be made for each reapplication directed and satisfactorily performed.] 1.1.7.2 [Measurement Protective coating will be measured for payment by determining the area satisfactorily covered to the nearest square meter yard.] 1.1.7.3 [Unit of measure Square meter yard.] 1.2 REFERENCES NOTE: This paragraph is used to list the publications cited in the text of the guide specification. The publications are referred to in the text by basic designation only and listed in this paragraph by organization, designation, date, and title. Use the Reference Wizard's Check Reference feature when you add a RID outside of the Section's Reference Article to automatically place the reference in the Reference Article. Also use the Reference Wizard's Check Reference feature to update the issue dates. References not used in the text will automatically be deleted from this section of the project specification when you choose to reconcile references in the publish print process. 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. ACI INTERNATIONAL (ACI)ACI 506.2(1995) Specification for ShotcreteASTM INTERNATIONAL (ASTM)ASTM A 185/A 185M(2007) Standard Specification for Steel Welded Wire Reinforcement, Plain, for ConcreteASTM C 270(2008a) Standard Specification for Mortar for Unit MasonryASTM C 387/C 387M(2008) Standard Specification for Packaged, Dry, Combined Materials for Mortar and Concrete1.3 DEFINITIONS 1.3.1 Foundations The rock foundation is comprised of the rock surfaces upon which [embankment] [and] [concrete] structures are placed. Vertical surfaces, where permitted or required by these specifications, are included. 1.3.2 Rock Joints Rock joints are all planar and/or curvilinear fractures, including cracks, crevices, and seams which separate a rock mass into individual rock blocks of various sizes. They may be open or closed and may be filled with material other than rock material. 1.4 SUBMITTALS NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL PROCEDURES and edit the following list to reflect only the submittals required for the project. Submittals should be kept to the minimum required for adequate quality control. A “G” following a submittal item indicates that the submittal requires Government approval. Some submittals are already marked with a “G”. Only delete an existing “G” if the submittal item is not complex and can be reviewed through the Contractor’s Quality Control system. Only add a “G” if the submittal is sufficiently important or complex in context of the project. For submittals requiring Government approval on Army projects, a code of up to three characters within the submittal tags may be used following the "G" designation to indicate the approving authority. Codes for Army projects using the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO" for District Office (Engineering Division or other organization in the District Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project Office. Codes following the "G" typically are not used for Navy, Air Force, and NASA projects. Choose the first bracketed item for Navy, Air Force and NASA projects, or choose the second bracketed item for Army projects. Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for [Contractor Quality Control approval.][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-03 Product Data Tools}[; _G][; _{G, [_____]}] Tabular list of light power tools to be used in lieu of hand tools, for approval prior to their use on the job site. PART 2 PRODUCTS 2.1 MATERIALS 2.1.1 Dental Concrete NOTE: Select the appropriate alternatives. Dental concrete shall conform to the requirements of [Section [[_____]] [_____]] [ASTM C 387/C 387M, normal weight and strength]. 2.1.2 Dental Mortar Dental mortar shall conform with ASTM C 270 or ASTM C 387/C 387M, Type N. 2.1.3 Shotcrete NOTE: Select appropriate alternative. Shotcrete shall conform to the requirements of [Section 03 37 13 SHOTCRETE] [ACI 506.2. The compressive strength of the concrete shall be 27.6 MPa 4000 psi]. 2.1.4 Welded Wire Fabric Welded wire fabric used shall be 150 by 150 mm 6 by 6 inches - W3 x W3, conforming to ASTM A 185/A 185M. 2.1.5 Filter Material NOTES: Information on the design of filter materials can be found in the Engineering Manual (ER) 1110-2-1901, "Seepage Analysis and Control for Dam," ER 1110-2-2300, "Earth and Rock Fill Dams General Design and Construction Considerations. The Specifier should use the first paragraph if there is a concrete section, an embankment for earth dams, or a stone protection section in the specifications and if the gradation therein is satisfactory for filter materials. If there is no concrete section, or if the gradation therein is unsatisfactory for filter materials, the Specifier should use the second paragraph. [Filter material shall consist of [sand and gravel] [and crushed stone]. [Sand and gravel] [and crushed stone] for filter materials shall meet the applicable requirements of [Section 03 70 00 MASS CONCRETE, paragraph MATERIALS] [Section 35 31 19 STONE, CHANNEL, SHORELINE/COASTAL PROTECTION FOR STRUCTURES, paragraph MATERIALS,] [Section 35 73 13 EMBANKMENT FOR EARTH DAMS, paragraph MATERIALS.]] [Filter material shall consist of [Sand,] [Gravel,] [Crushed Stone]. The [filter material] shall be composed of tough, durable particles, reasonably free from thin, flat and elongated pieces, and shall contain no organic matter nor soft, friable particles in quantities considered objectionable by the Contracting Officer. Grading shall conform to the following requirements:                                                  PERMISSIBLE LIMITS         U.S. STANDARD SIEVE                  PERCENT BY WEIGHT, PASSING                                 SAND               [______]                               [_____]               [______]                               [_____]               [______]                               [_____]                                GRAVEL "D"               [______]                               [_____]               [______]                               [_____]               [______]                               [_____]                                                  PERMISSIBLE LIMITS         U.S. STANDARD SIEVE                  PERCENT BY WEIGHT, PASSING                                CRUSHED STONE               [_____]                                [_____]               [_____]                                [_____]               [_____]                                [_____] The [filter materials] shall be well-graded between the limits shown. [Gravel shall not be crushed stone.] At least one test shall be performed on each 1000 tons (metric) 2,000,000 lb to be delivered to the project site for each gradation band. All points on individual grading curves obtained from representative samples of [filter material] shall lie between the boundary limits as defined by smooth curves drawn through the tabulated grading limits plotted on a mechanical analysis diagram. The individual grading curves within these limits shall not exhibit abrupt changes in slope denoting either skip grading or scalping of certain sizes or other irregularities which would be detrimental to the proper functioning of the filter.] PART 3 EXECUTION 3.1 EXAMINATION The limits of the proposed foundations for the various parts of the work are approximately as indicated. The Contracting Officer reserves the right to change the depth to, or the width of, the foundations if, conditions exposed in the foundation excavations, or as determined by exploratory drilling, warrant such modifications. 3.2 PREPARATION 3.2.1 Equipment 3.2.1.1 _Tools Hand tools, where required or permitted by these specifications include, but are not limited to [shovels,] [bars,] [picks,] [wedges,] [and] [brooms]. Light power tools may be used in lieu of hand tools only when such use is approved. 3.2.1.2 Air Jet An air jet shall consist of a [40] [_____] mm [1-1/2] [_____] inch nozzle with a supply hose connected to a suitable source of compressed air. The compressed air shall have a pressure between [620] [_____] and [760] [_____] kPa [90][_____] and [110] [_____] psi. The compressed air shall be controllable at the nozzle. 3.2.1.3 Air/Water Jet An air/water jet shall consist of a [40] [_____] mm [1-1/2][_____] inch nozzle with associated controls and supply hoses connected to suitable sources of compressed air and water. Compressed air shall have a pressure between [620] [_____] and [760] [_____] kPa [90] [_____] and [110] [_____] psi. Water shall be introduced into the airstream at the nozzle when needed, at a rate of up to [2] [_____] L/s [30] [_____] gpm. The air and water shall be separately controllable at the nozzle. 3.2.1.4 Water Jet A water jet shall consist of a [25] [_____] mm [1] [_____] inch nozzle with a supply hose connected to a suitable source of water. The system shall be capable of delivering up to [13] [_____] L/s [200] [_____] gpm. The flow rate shall be controllable at the nozzle. 3.3 PRELIMINARY CLEANUP When the excavation has reached the approximate limits shown or when the Contracting Officer determines that a satisfactory foundation may have been reached, the Contracting Officer may direct that a preliminary cleanup be performed on all or any part of the rock foundation surface. This cleanup shall consist of removing all debris, loose rock, sand, silt, and other objectionable material by hand tools followed by [air] [water] [air/water] jets or any combination of additional methods approved or directed. The Contracting Officer may require that the excavation be continued and the preliminary cleanup procedure repeated until a satisfactory foundation surface is reached. 3.4 FINAL CLEANUP AND FOUNDATION PREPARATION NOTE: Insert a description of the areas to receive (this type) foundation preparation. Where more than one type of final cleanup and foundation preparation is needed, this paragraph may be repeated with appropriate variations. See EM 1110-2-2300 for guidance on where foundation preparation should be required under embankment dams. Compacted filter material should be used under overhangs only when granular fill is being placed against the foundation. Unless otherwise directed, Final Cleanup and Foundation Preparation [, Structural] [, Embankment] [, Type [_____]] shall be performed [_____]. This work shall consist of removing loose and/or weather rock and pockets of fines, sand, rock rubble or gravel and other objectionable material from the in place rock surface including areas of depression, large crevices, and open rock joints. [The loose material need not be removed where the width of the opening is less than [_____] mm inches.] [Mechanical equipment may be used but such equipment will be rubber tired only.] Picking, barring, and hand excavation may be necessary to obtain a foundation surface free from loose, drummy, or shattered materials. [Irregularities in the rock surfaces shall be trimmed to form a reasonable uniform slope on the abutments.] [Slopes shall not be steeper than [_____] vertical on [_____] horizontal.] [Overhangs shall not be permitted at any location.] [Overhangs shall be excavated and backfilled with compacted [filter] [granular] materials. Placement of such filter materials shall be in accordance with the provisions contained in Section [[_____]] [_____].] [Vertical surfaces shall not be [permitted.] [higher than [_____] m feet] and benches between vertical surfaces shall be of such width so as to provide a stepped slope comparable to the adjacent uniform slope.] The final rock surface shall be thoroughly cleaned by use of [air jets] [water jets] [air/water jets] or other approved method and shall be maintained in a clean condition until the placement of [embankment] [or] [concrete] thereon. 3.5 DENTAL TREATMENT NOTE: If a schedule is not provided, a description of the areas to receive dental treatment, and the minimum width joint to be treated should be included. For embankment dams, the minimum width joint to be treated depends on the gradation of the embankment material that will be placed against the joint (see EM 1110-2-2300). Dental treatment shall consist of excavation, if necessary, of the material in joints, cavities, depressions, and overhangs and the placement of [concrete] [or] [mortar] such that the final surface is satisfactory for the subsequent placement of [embankment] [or] [concrete]. [Unless otherwise directed, Dental Treatment shall be performed in accordance with the following schedule:    Foundation                               Minimum Width Joint      Area                                     to be treated    [_____]                                       [_____]    [_____]                                       [_____]] Joints and cavities shall be excavated to a depth [3] [_____] times the width (measured at the base of the excavation) of the joint or cavity. 3.5.1 Dental Concrete NOTE: Normally the concrete specification will be included in Division 3, Concrete. When Division 3 would not otherwise be included, and only small quantities will be needed, the ASTM alternate may be used. The maximum aggregate size in dental concrete should not be more than one third the minimum widths of joints in which it is to be used. Concrete shall be used to fill joints, cavities, depressions, and overhangs except where the use of mortar is required or permitted. Prior to placement, the surfaces of the joint, cavity, depression, or overhang will be thoroughly cleaned using [air] [or] [air/water] [or] [water] jets. The maximum aggregate size shall be [[_____] mm inch] [as directed]. The concrete shall conform with paragraph MATERIALS. 3.5.2 Dental Mortar Mortar shall be used to fill joints, cavities, depressions, and overhangs when the width of the opening is less than [_____] mm inches and at other areas as directed or approved. Placement of the sand-cement mortar will be accomplished by [troweling] [brooming] the mortar [with stiff bristled brooms] into the cleaned joints, cracks, and crevices so as to provide a thorough seal. The surface moisture of the rock shall be such that absorption of water from the mortar mix will be minimized. However, no standing water will be allowed. All mortar which cannot be worked into the joints, shall be removed from the rock surface. [The mortar shall be moist cured for a period of at least [_____].] The mortar shall conform with paragraph MATERIALS. 3.6 PROTECTIVE TREATMENT NOTE: Insert here a description of the areas to be protected, and the type(s) of protection to be used. If more than one type of protection is specified, it should be clear which method(s) is (are) required for each area. If the choice of methods is optional with the Contractor that should be stated. Care should be used when selecting protective measures. Not all methods are suitable in all situations or with all types of rock. Of the following paragraphs, only those methods specified should be included. Protective treatment shall be [_____]. 3.6.1 Wetting Keep the area wet by [continuous spraying] [flooding] or by other approved method. [Provide positive measures to control the runoff.] 3.6.2 Shotcrete NOTE: See ACI 506.2 for additional options that may be specified and for guidance on their use. The first alternate should be used if shotcrete is being used for other purposes on the job, or if a different shotcrete specification is appropriate. Alternate 1: [Shotcrete shall conform to the requirements of paragraph MATERIALS.] Alternate 2: [The area to be protected shall be covered by welded wire fabric in accordance with paragraph MATERIALS.] The fabric shall be securely anchored in place as shown on the contract drawings. The shotcrete shall conform to paragraph MATERIALS. The Contractor is responsible for construction and preconstruction testing. [Gradation [_____] will be used.] [Gradations [_____] or [_____] will be used.] The minimum cover [over reinforcement,] shall be [_____] mm inches. 3.6.3 Protective Coating NOTE: Celtite 42-51 HI-SEAL, (42-52C (Clear)), and (45-51W (White)) epoxy resin and emulsion, manufactured by Celtite, Inc., telephone 1-800-626-2948 and Aero-Spray, manufactured by American Cyanamid/CYTEC, telephone 1-800-835-9844, (Mining Products Division) have been successfully used and were available at time of publication. However, the availability of these and similar products should be investigated before their use is specified. Asphaltic emulsions have been used, with limited success, in some applications. Apply an approved protective coating within [_____] hours of exposure of the rock surface in accordance with the manufacturer's recommendations or as otherwise approved. Reapply the coating as necessary to repair damage caused by construction activities or when needed to provide adequate protection. [The protective coating shall be [_____], or equal.] 3.6.4 Protective Backfill The final [600] [_____] mm [2] [_____] feet of excavation, final cleanup and foundation preparation, inspection, [dental treatment,] and placement of the first [300] [_____] mm [12] [_____] inches of backfill shall all be accomplished within a period of [16] [_____] hours. Within [48] [_____] hours after the start of the final excavation, the backfill shall have a minimum thickness of [1000] [_____] mm [3] [_____] feet. The backfill shall be placed in accordance with the requirements of Section [[_____]] [_____]. 3.6.5 Protective Concrete The final [600] [_____] mm [2] [_____] feet of excavation, [cleanup,] inspection, preparation, [dental treatment,] and placement of at least [_____] mm inches of protective concrete, shall all be accomplished within a period of [_____] hours. The concrete shall conform to the requirements of Section [[_____]] [_____]. 3.6.6 Temporary Earth Cover NOTE: Insert the requirements of the material to be used. [Within [_____] hours of excavation,] [Before freezing weather is expected,] [Before other construction activities are permitted,] the area will be protected by a temporary earth cover [_____] mm feet thick. The material shall [_____]. The material shall be removed and the area [cleaned,] [inspected,] [and prepared] prior to placement of [embankment] [or] [concrete] thereon. 3.7 TESTS 3.7.1 General Establish and maintain quality control for foundation preparation operations to assure compliance with contract specifications and maintain records of the quality control for all operations including but not limited to the following: 3.7.1.1 Equipment Quantity and type. 3.7.1.2 Foundation Excavation Strict adherence to foundation excavation limits and depths. 3.7.1.3 Inspection, Mapping, and Cleanup Orderly prosecution of inspections, mapping, and cleanup of foundation excavation areas. 3.7.1.4 Specialized operations Protective treatment [and Dental treatment]. 3.7.2 Reports Submit three copies of these records of inspection as well as corrective action taken daily. 3.8 FOUNDATION INSPECTION AND GEOLOGIC MAPPING Inspections to determine adequacy of the foundations will be performed by the Contracting Officer in all foundation areas between completion of excavation and placement of [embankment,] [or] [concrete,] [or protective treatment]. The Contractor will cooperate to the extent necessary to assist in inspection and mapping activities which may require additional survey control points and access. Coordinate the schedule for foundation excavation and preliminary cleanup with the Contracting Officer to ensure that the cleanup, inspection, and mapping proceed in an orderly manner.