USACE / NAVFAC / AFCESA / NASA UFGS-32 16 15 (April 2008) -------------------------- Preparing Activity: USACE Superseding UFGS-32 16 15 (April 2006) UNIFIED FACILITIES GUIDE SPECIFICATIONS References are in agreement with UMRL dated January 2009 SECTION 32 16 15 CONCRETE BLOCK PAVEMENTS 04/08 NOTE: This guide specification covers the requirements for constructing a concrete block pavement. 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 1.1 PAYMENT PROCEDURES NOTE: Delete this paragraph in fixed price contracts. 1.1.1 Pavements The blocks, cut blocks, bedding sand, and jointing sand will be paid per square meter foot of satisfactorily installed block pavement surface. 1.1.2 Edge Restraint The edge restraint will be paid per lineal meter foot of satisfactorily installed edge restraint. 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 301(2005; Errata 2008) Specifications for Structural ConcreteAMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS (AASHTO)AASHTO M 133(2008) Standard Specification for Preservatives and Pressure Treatment Processes for TimberASTM INTERNATIONAL (ASTM)ASTM C 117(2004) Standard Test Method for Materials Finer than 75-um (No. 200) Sieve in Mineral Aggregates by WashingASTM C 131(2006)Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles MachineASTM C 136(2006) Standard Test Method for Sieve Analysis of Fine and Coarse AggregatesASTM C 67(2008) Standard Test Methods for Sampling and Testing Brick and Structural Clay TileASTM C 936(2008) Solid Concrete Interlocking Paving UnitsASTM C 979(2005) Pigments for Integrally Colored ConcreteASTM D 4318(2005) Liquid Limit, Plastic Limit, and Plasticity Index of SoilsASTM D 75(2003) Standard Practice for Sampling AggregatesASTM E 11(2004) Wire Cloth and Sieves for Testing Purposes1.3 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-04 Samples Concrete Paving Block}[; _G][; _{G, [_____]}] A sample of five paving blocks prior to the start of the work. Also, a representative sample of not less than 15 blocks as directed by the Contracting Officer, from each lot of 20,000 concrete paving blocks or fraction thereof. _{SD-06 Test Reports Tests, Inspections and Verifications} A written report within 7 calendar days after completion of the work, covering the testing required for each lot. 1.4 MAINTENANCE NOTE: This paragraph will be included only if the project has aesthetic considerations where future maintenance must exactly match the color of the block. At the completion of work provide [_____] paving blocks matching those used in the project. These paving blocks shall be delivered stacked on pallets. PART 2 PRODUCTS 2.1 MATERIALS 2.1.1 Bedding and Jointing Sand NOTE: If the pavement is to be subjected to Design Index traffic of 8 or higher, both the bedding and jointing sands will consist of 100 percent crushed sand, if it is available in the construction locale. For block pavements to be used for walkway, driveway, storage area, parking area, or subject to traffic Design Indexes of 1 or 2, the bedding sand gradation can be changed to the fine aggregate gradation in ASTM C 33 with the additional requirement of 0-10 percent passing the 0.075 mm (No. 200) sieve. Use two separate sand gradations for the bedding layer and in the block joints. Both sand gradations shall consist of crushed sand, natural sand, or a combination of crushed and natural sand. Both sand gradations shall have a minimum L.A. Abrasion of 40 percent when tested in accordance with ASTM C 131. Both sand gradations shall be nonplastic when tested in accordance with ASTM D 4318 and shall be free of lumps, clay, vegetation, soft particles, sulphates, and other contaminants. The bedding and jointing sands shall conform to the following gradations, determined in accordance with ASTM C 136 and ASTM C 117, using ASTM E 11sieve.                                          Percent Passing                                         _________________                   Sieve                 Bedding Sand        Jointing Sand  (ASTM E 11)  ______________________        ______________      _______________           9.5 mm                    100                  100           4.75 mm                  80-100                100           2.36 mm                  60-90                95-100           1.18 mm                  25-70                70-100           0.600 mm                 10-35                40-75           0.300 mm                  5-20                10-40           0.150 mm                  0-10                 2-25           0.075 mm                  0-5                  0-10                                        Percent Passing                                        _________________                   Sieve                 Bedding Sand        Jointing Sand  (ASTM E 11)  _______________________       ______________      _______________           3/8 in.                   100                  100           No. 4                    80-100                100           No. 8                    60-90                95-100           No. 16                   25-70                70-100           No. 30                   10-35                40-75           No. 50                    5-20                10-40           No. 100                   0-10                 2-25           No. 200                   0-5                  0-10 2.1.2 _{Concrete Paving Block} NOTE: Color and shape of block may be specified. Check local availability of specific colors or shapes before specifying. Organic pigments should not be used, since they are unstable in the alkaline concrete environment and subject to weathering. Shape is generally rectangular or interlocking. The concrete paving block shall conform to ASTM C 936, and shall be [_____] thick, [_____] in color, and [_____] in shape. Pigmentation shall conform to ASTM C 979. 2.1.3 Edge Restraints 2.1.3.1 Treated Wood NOTE: Treated wood edge restraint is only acceptable for walkways and residential driveways. Delete this paragraph when this option is not retained. The edge restraint shall be wood treated in accordance with AASHTO M 133 and of dimensions shown on the plans. 2.1.3.2 Precast Concrete NOTE: Minimum compressive strength of precast concrete should be 21 MPa (3,000 psi) unless analysis requires some other value. Entrained air content of the fresh concrete should be 6 percent plus or minus 1.5 percent in areas where freezing and thawing coverage is a design consideration. Delete this paragraph when this option is not retained. The edge restraint shall be precast portland cement concrete elements with the dimensions shown on the plans. The precast concrete shall have a compressive strength of not less than [_____] at 28 days and an entrained air content of not less than [_____]. 2.1.3.3 Cast-in-Place Concrete NOTE: Minimum compressive strength of cast-in-place concrete should be 21 MPa (3,000 psi) unless analysis requires some other value. Entrained air content of the fresh concrete should be 6 percent plus or minus 1.5 percent in areas where freezing and thawing coverage is a design consideration. Delete this paragraph when this option is not retained. The edge restraint shall be portland cement concrete placed with the dimensions shown in the plans. Concrete shall conform to the requirements of ACI 301, except that it shall have a compressive strength of not less than [_____] at 28 days and an entrained air content of not less than [_____]. 2.2 _{TESTS, INSPECTIONS AND VERIFICATIONS} 2.2.1 Paving Block NOTE: Sampling of paving blocks prior to the start of the work for the purposes of verifying the color and shape of the blocks will only be required when these considerations are critical to the project aesthetics. For jobs of less than 1000 square meters (10,000 square feet) or for pavements not to be exposed to vehicular traffic, a manufacturer's certificate which certifies that the paving blocks meet the requirements of ASTM C 936 can be accepted in lieu of sampling and testing the blocks of each lot. Conduct the tests prescribed by ASTM C 936 and the following tests on the remaining 13 blocks of each sample from each lot. 2.2.1.1 Freezing and Thawing NOTE: The freezing and thawing test may be waived for climates not subject to freezing and thawing. For jobs of less than 1000 square meters (10,000 square feet), a manufacturer's certificate which certifies that the paving blocks meet the requirements of this paragraph may be accepted in lieu of sampling and testing the blocks of each lot. Determine resistance to freezing and thawing in accordance with Section 8 of ASTM C 67 for five blocks. The blocks shall have no breakage and no more than 1.0 percent loss of any individual unit in dry weight when subjected to 50 cycles of freezing and thawing. 2.2.1.2 Dimensional Tolerance The length and width of each block in the sample shall not vary from any other block in this or any other lot sample by more than 3 mm 1/8 inch. Thickness of any block in the sample shall not vary by more than 3 mm 1/8 inch from the specified block thickness. 2.2.1.3 Retest Notify the Contracting Officer if any blocks fail to meet the specified requirements. In case the shipment fails to conform to the specified requirements, the Contractor may sort it, and new specimens selected from the retained lot for retesting, as directed by the Contracting Officer. All concrete paving block retests shall be performed at the expense of the Contractor. In case the second set of specimens fail to conform to the test requirements, the entire lot shall be rejected. 2.2.2 Sand Obtain a representative sample in accordance with ASTM D 75 from each 75 cubic meters 100 cubic yard of sand to be used in the project. If the sand fails to meet the gradation requirements the Contractor may take another sample and retest it at no cost to the Government. If this retest fails or if no second test is taken, the sand is rejected by the Government and shall be removed from the job site. PART 3 EXECUTION NOTE: The base course for the block pavement must be a dense graded or bound material to avoid loss of the sands from the bedding layer. It must also be properly graded and leveled. A smoothness of no more than 10 mm (3/8 inch) deviation from a 3 m (10 foot) straight edge is needed. The project specification for the pavement base course should be checked to ensure these requirements are met. 3.1 PREPARATION 3.1.1 Edge Restraint Location Install the edge restraint as shown in the drawings prior to placement of the blocks. 3.1.2 Sand Bedding Layer The bedding sand shall be spread evenly over the area to be paved and shall be screeded to an uncompacted average thickness of 30 mm 1-1/4 inch with a tolerance for grade and surface smoothness of plus or minus 6 mm 1/4 inches . This bedding sand shall not be used to fill low areas that exceed the specified tolerance for the base. The sand shall be left uncompacted and shall not be disturbed by any pedestrian or vehicle construction traffic. 3.2 BLOCK PLACEMENT NOTE: Paving block to be subject to vehicular traffic should be placed in herringbone pattern, and this pattern can be specified here. The paving block shall be placed by hand or machine in the indicated pattern. Placement of paving block shall start from a corner or straight edge and proceed forward over the undisturbed sand bedding layer. The joints, excluding any chamfer between paving blocks, shall be not less than 2 mm 1/16 inch or more than 6 mm 1/4 inch in width. After seating, the block surface shall be flush or up to 6 mm 1/4 inch above the edge restraint. 3.2.1 Unfilled Gaps Any gaps between paving blocks and any edge restraint, drainage structures, or other members that cannot be filled with a whole block shall be filled with a paving block cut to fit the gap, except that slivers will not be allowed and the minimum size of cut block shall be [_____]. Cutting shall be done with a hydraulic splitter, a masonry saw, or other device that accurately leaves a clean, vertical face without spalling. Any remaining gap between the block and adjoining edge restraint or structure greater than 6 mm 1/4 inch will not be accepted; adjacent blocks shall be cut or rearranged to prevent this. 3.2.2 Seating Blocks The blocks shall be seated in the bedding sand by compacting them with a minimum of three passes of a vibratory plate compactor, sized as follows: [_____]. 3.2.3 Jointing Sand The jointing sand shall be swept into joints and vibrated with a vibratory plate or vibratory roller compactor. This process shall be continued until sweeping and vibrating have filled all joints with sand and further vibration cannot force additional sand into the joints. The coarser particles of the sand will not enter the joints and will remain on the surface. These particles and any excess sand shall be swept off the pavement. 3.2.4 Timing of Operations Seating of blocks and placement of jointing sand can be done concurrently with block placement. However, seating of blocks and placement of jointing sand shall not be done within 1.5 m 5 feet of any unfinished edge of the block pavement that is not supported by the edge restraint. 3.2.5 Final Rolling NOTE: This paragraph can be deleted for light load pavements such as driveways or pedestrian walkways. The final finished paving block surface shall be rolled with four passes of a vibratory or pneumatic roller with a static weight of not less than 4.5 metric tons 10,000 pounds. 3.2.6 Construction Traffic Construction traffic shall not be allowed on the paving block surface until the jointing sand has been placed and vibrated into the joints and all debris and excess sand has been swept off. 3.3 CLEANUP Sweep the entire pavement surface and remove all excess sand, blocks and debris from the project area. 3.4 SMOOTHNESS AND GRADE TOLERANCES 3.4.1 Smoothness No portion of the finished pavement surface shall deviate by more than 10 mm 3/8 inch from a 3 m 10 foot long metal straightedge placed on the pavement surface. 3.4.2 Block Height The finished block surface shall be either flush or up to 6 mm 1/4 inch higher than all edge restraints or drainage structures. 3.4.3 Grade The finished pavement shall be within 12 mm 0.04 feet of planned grade shown on the plans. 3.4.4 Remedial Action Any area not meeting the smoothness, block height, or grade tolerance shall be taken up, adjustments made, and the blocks relaid.