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Recommended EPS-Block Geofoam Standard for Lightweight Fill in Road Embankments and Bridge Approach Fills on Soft Ground

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1 RECOMMENDED EPS-BLOCK GEOFOAM STANDARD FOR LIGHTWEIGHT FILL IN ROAD EMBANKMENTS AND BRIDGE APPROACH FILLS ON SOFT GROUND 1 SCOPE sibility for the design of the portions of the project that include the proposed embankment. 1.1 This document is a recommended material, product, Molder: The company actually manufacturing the EPS and construction standard covering block-molded expanded blocks used as the EPS-block geofoam for the proposed polystyrene (EPS) for use as a geofoam geosynthetic product embankment. (EPS-block geofoam) in road applications involving embank- Primary Molder: When more than one molder will sup- ments and related bridge approach fills on soft ground. This ply EPS blocks to a project under a given contract, this document is a recommended material purchasing standard, and is the molder who is selected or designated as having project-specific review of its use is required. authority to conduct business on behalf of all molders 1.2 This document is not a recommended design stan- and who is ultimately responsible for the product qual- dard, but includes technical information used in design. ity of all molders. This document is intended to be used in conjunction with the Owner: The government agency having contractual recommended design guideline. All information concerning authority over the proposed embankment at the time of this report should be obtained from the Transportation its construction. This may or may not be the government Research Board (TRB). agency having final ownership or jurisdiction over the operation and maintenance of the proposed road. For example, a state department of transportation (DOT) 2 REFERENCED DOCUMENTS may oversee construction on behalf of a local (i.e., county 2.1 AASHTO Standards: none. or town) jurisdiction. In this case, the DOT would be con- 2.2 ASTM Standards:1 sidered the owner for the purposes of this recommended standard. C 578-95--Standard Specification for Rigid, Cellular Owner's Agent: The organization (typically a govern- Polystyrene Thermal Insulation. ment agency or private consulting company) having re- C 303-98--Standard Test Method for Dimensions and sponsibility for inspection during construction of the pro- Density of Preformed Block and Board-Type Thermal posed embankment. This organization may or may not be Insulation. the designer. Supplier: The company having the contractual relation- 2.3 NCHRP reports:2 ship with the contractor for the supply of the EPS-block geofoam. This company may be the molder or primary RECOMMENDED EPS-BLOCK GEOFOAM STANDARD NCHRP Web Document 65: Geofoam Applications in molder directly or an intermediary company (typically a the Design and Construction of Highway Embankments. distributor of construction and/or geosynthetic products manufactured by others). 3 TERMINOLOGY 4 PRODUCT MANUFACTURING QUALITY CONTROL REQUIREMENTS For the purposes of this standard, the following terminol- ogy is used for the various parties involved: 4.1 Manufacturing quality control (MQC) of the EPS- block geofoam product is the primary responsibility of the Contractor: The company having the direct contractual molder or primary molder. The purpose of this section is relationship with the owner for construction of the pro- to define the parameters for use by a molder or primary posed embankment and responsibility for its overall molder in developing an MQC plan. These parameters will construction. also be those measured as part of the manufacturing quality Designer: The organization (typically a government assurance (MQA) to be conducted by the owner's agent. agency or private consulting company) having respon- MQA requirements are detailed in sections 5, 6, and 8 of this standard. 1 Available from the American Society for Testing and Materials; 100 Barr Harbor 4.2 All EPS-block geofoam shall consist entirely of Drive; West Conshohocken, Pennsylvania 19428-2959. 2 Available from the Transportation Research Board; 500 Fifth St., N.W.; Washington, expanded polystyrene. At the discretion of the molder or D.C., 20001. http://gulliver.trb.org/publications/nchrp/nchrp_w65.pdf. primary molder, the EPS-block geofoam may consist of some

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2 mixture of virgin raw material and recycled EPS material. taken from actual blocks produced for the project. The actual However, if regrind is to be used, its use shall be clearly blocks should be covered by this standard for either MQC stated by the molder or primary molder as part of the Phase I by the molder or MQA by the owner's agent as described in MQA, pre-construction, pre-certification process described Section 8 of this standard. All test specimens shall be in Section 6. The source of the regrind (block-molded seasoned as specified in ASTM C 578. Dry density/unit versus shape-molded EPS, in-plant versus post-consumer) weight, compressive strength, and flexural strength shall be shall also be stated clearly. measured as specified in ASTM C 578. The specimens used 4.3 All EPS-block geofoam shall be adequately seasoned for compressive testing shall be cubic in shape with a 50-mm prior to shipment to the project site. For the purposes of this (2-in.) face width. A strain rate of 10 percent per minute shall standard, seasoning is defined as storage in an area suitable be used for the compressive strength tests. Both the elastic- for the intended purpose as subsequently defined herein for a limit stress and the initial tangent Young's modulus shall minimum of 72 hours at normal ambient room temperature be determined in the same test used to measure compressive after an EPS block is released from the mold. Seasoning shall strength. The elastic-limit stress is defined as the measured be done within a building or other structure that protects the compressive normal stress at a compressive normal strain of EPS blocks from moisture as well as ultraviolet (UV) radiation. 1 percent. The initial tangent Young's modulus is defined as The area in which EPS blocks are stored for seasoning shall the average slope of the compressive stress versus compressive also be such that adequate space is allowed between blocks and strain curve between 0-percent and 1-percent strain. such that positive air circulation and venting of the structure are 4.7 Each EPS block shall meet dimensional tolerances, as provided so as to foster the outgassing of blowing agent and determined in three distinct areas: trapped condensate from within the blocks. The owner's agent shall be allowed to inspect the structure(s) to be used for Variations in linear dimensions, as defined in Section seasoning upon request and during normal business days and 4.8. hours. The molder or primary molder may request a shortened Deviation from perpendicularity of block faces, as defined seasoning period if the EPS blocks are seasoned within an in Section 4.9. appropriate heated storage space and the molder or primary Overall warp of block faces, as defined in Section 4.10. molder demonstrates to the satisfaction of the owner's agent that the alternative seasoning treatment produces blocks that 4.8 The thickness, width, and length dimensions of an equal or exceed the quality of blocks subjected to the normal EPS block are defined herein as the minimum, intermediate, 72-hour seasoning period. and maximum overall dimensions of the block, respectively, 4.4 All EPS-block geofoam shall satisfy the product as measured along a block face. These dimensions of each flammability requirements specified in ASTM C 578. block shall not deviate from the theoretical dimensions by 4.5 Table 1 indicates the AASHTO material type more than 0.5 percent. designations used for the different densities/unit weights of 4.9 The corner or edge formed by any two faces of an EPS blocks that are covered by this standard. Only these EPS block shall be perpendicular, i.e., form an angle of material type designations shall be used in any correspondence 90 degrees. The deviation of any face of the block from a theo- or other communication related to this project. For a given retical perpendicular plane shall not exceed 3 mm (0.12 in.) material type, the dry density/unit weight of each EPS block over a distance of 500 mm (20 in.). (as measured for the overall block as a whole) after the period 4.10 Any one face of a block shall not deviate from RECOMMENDED EPS-BLOCK GEOFOAM STANDARD of seasoning, as defined in Section 4.3, shall equal or exceed planarity by more than 5 mm (0.2 in.) when measured using that shown in Table 1. The dry density/unit weight shall be a straightedge with a length of 3 m (9.8 ft). determined by measuring the mass/weight of the entire block by weighing the block on a scale and dividing the mass by the volume of the block. The volume shall be determined 5 PRODUCT MANUFACTURING QUALITY by obtaining dimensional measurements of the block in ASSURANCE: GENERAL REQUIREMENTS accordance with ASTM test method C 303. 4.6 Table 2 gives the minimum allowable values of 5.1 MQA of the EPS-block geofoam product will be various material parameters corresponding to each AASHTO conducted to verify the molder's MQC procedures. The material type shown in Table 1. These material parameters are owner's agent will have primary responsibility for all MQA to be obtained by testing specimens prepared from samples unless the owner notifies the contractor otherwise. The TABLE 1 AASHTO material type designations for EPS-block geofoam Material Designation Minimum Allowable Density/Unit Weight, kg/m3 (lbf/ft3) AASHTO Any Test MQC/MQA (proposed) ASTM C 578 Each Block as a Whole Specimen EPS40 I 16 (1.0) 15 (0.90) EPS50 VIII 20 (1.25) 18 (1.15) EPS70 II 24 (1.5) 22 (1.35) EPS100 IX 32 (2.0) 29 (1.80)

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3 TABLE 2 Minimum allowable values of MQC/MQA parameters for individual test specimens Dry Density/ Unit Weight, Compressive Flexural Elastic Limit Initial Tangent Material kg/m3 Strength, Strength, kPa Stress, kPa Young's Modulus, Designation (lbf/ft3) kPa (lbs/in2) (lbs/in2) (lbs/in2) MPa (lbs/in2) EPS40 15 (0.90) 69 (10) 173 (25) 40 (5.8) 4 (580) EPS50 18 (1.15) 90 (13) 208 (30) 50 (7.2) 5 (725) EPS70 22 (1.35) 104 (15) 276 (40) 70 (10.1) 7 (1015) EPS100 29 (1.80) 173 (25) 345 (50) 100 (14.5) 10 (1450) owner's agent will communicate directly only with the con- molder must have a program in order for third-party certifi- tractor in matters and questions of MQA unless all parties cation to be indicated, and the primary molder must take agree otherwise. responsibility for coordinating the third-party certification of 5.2 MQA of the EPS-block geofoam will consist of two all molders. phases. Phase I MQA consists of pre-certification of the 6.3 If third-party certification is offered, this notification molder and shall be conducted prior to shipment of any EPS shall be accompanied by documentation that identifies the blocks to the project site. Phase I MQA is covered in Sec- business entity providing the third-party certification and de- tion 6 of these specifications. Phase II MQA shall be conducted scribes in detail the steps to be taken by this agency to verify as the EPS blocks are delivered to the project site and is the molder's compliance with the specific requirements of discussed in Section 8 of these specifications. Table 3 this specification. Acceptance of the molder's third-party provides a summary of the MQA procedures. certification by the owner's agent will waive the need for pre- construction product submittal and testing as specified in Section 6.4. When there are multiple molders, third-party 6 PRODUCT MANUFACTURING QUALITY certification must be acceptable for each and every molder; ASSURANCE: PHASE I otherwise, it will be denied for each and every molder. 6.4 If the molder does not have third-party certification or 6.1 No EPS blocks shall be shipped to the project site the certification is deemed unacceptable by the owner's until such time as all parts of Phase I MQA have been com- agent, the contractor shall deliver a minimum of three full- pleted in the order listed and as specified in this section. size EPS blocks for each AASHTO EPS-block geofoam type 6.2 The contractor shall first indicate in writing to the to be used on the project to a location specified by the owner's agent whether the molder has a third-party certification owner's agent. When there are multiple molders, there shall program in force. When there are multiple molders, each be three blocks from each molder. These blocks shall in all TABLE 3 MQA procedures for EPS-block geofoam used for the function of lightweight fill in road embankments RECOMMENDED EPS-BLOCK GEOFOAM STANDARD Phase Sub- Start of Description Requirements Possible Actions phase Phase I None Prior to shipment Pre- Approved third-party certification: Molder will Acceptance of the molder's third-party to the project site certification of Identify the organization providing this certification by the owner's agent will the molder service. waive the need for pre-construction product Provide detailed information as to the submittal and testing. procedure and tests used by this organization No EPS blocks shall be shipped to the to verify the molder's compliance with the project until such time as all parts of Phase I specific requirements of this specification. MQA have been completed. Provide written certification that all EPS blocks supplied to the project will meet the requirements specified in the project specifications. No approved third-party certification: Contractor shall deliver a minimum of three full-size EPS blocks for each AASHTO EPS- block geofoam type to be used on the project to a location specified by the owner's agent. Owner's agent will weigh, measure, sample, and test a random number of blocks. Sampling and testing protocol will be the same as for Phase IIc MQA. Molder should submit a letter stating that all EPS blocks supplied for the project are warranteed to meet specification requirements and identifying what MQC measures the molder employs. (continued on next page)

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4 TABLE 3 (Continued) Phase Sub- Start of Description Requirements Possible Actions phase Phase II IIa As the EPS blocks On-site visual Approved third-party certification: Any blocks with significant physical are delivered to inspection of For each truckload, owner's agent should damage or not meeting specifications will the project site each block inventory each and every block. be (a) rejected on the spot and placed in an delivered to No approved third-party certification: area separate from those blocks that are the project site For each truckload, owner's agent should accepted or (b) marked "unacceptable" and to check for inventory each and every block. returned to the supplier. damage as well as visually verify the labeled information on each block II IIb As the EPS blocks On-site Approved third-party certification: If the selected block meets specifications are delivered to verification For each truckload, initially, only one block with respect to its size and shape, and the the project site that the per load should be tested to ensure that the mass agrees with the mass marked on the minimum minimum block dry density, as well as the block, no further checking of the load for block dry physical tolerances, meet specifications. these parameters is required and the density, as No approved third-party certification: shipment is approved conditionally until the well as the For each truckload, each block for the first Phase IIc test results verify that the block physical load and at least one block per load for meets specifications. tolerances, subsequent truckloads should be tested to If the selected block does not meet meet ensure that the minimum block dry density, specifications, then other blocks in the specifications as well as the physical tolerances, meet truckload should be checked and none used specifications. until the additional checking has determined which blocks are unsatisfactory. At the completion of this subphase, the construction contractor should be conditionally (until the Phase IIc test results verify that the blocks meet specifications) allowed to proceed with installing blocks. II IIc As the EPS blocks Confirming Approved third-party certification: Portions of sampled blocks that are not are delivered to the EPS Use the discretion of the owner's CQA damaged or otherwise compromised by the the project site engineering agent. For example, parameter confirmation sampling can be used as desired by the design can be omitted entirely on a small project, contractor. parameters can be performed only at the beginning of a If unsatisfactory test results are obtained, related to project, or can be done on an ongoing basis. the contractor may be directed to remove stiffness as No approved third-party certification: potentially defective EPS blocks and well as the Parameter confirmation should be performed replace them with blocks of acceptable quality control on all projects throughout the entire duration quality at no additional expense to the strength of the project. owner. parameters For each AASHTO EPS-block geofoam RECOMMENDED EPS-BLOCK GEOFOAM STANDARD type, at least one block will be selected for sampling from the first truckload. Additional blocks may be selected at a rate of sampling not exceeding one sample for every 250 m3 (325 yd3). Sampling is to be performed per the locations indicated in Table 2. Laboratory tests should be performed to check for compliance with the parameters shown in Table 2 to include the elastic- limit stress, initial tangent Young's modulus, compressive strength, and flexural strength. II IId As the EPS blocks As-built The owner's agent, with the cooperation of are placed drawing(s) the contractor, will prepare as-built drawing(s) as well as perform additional record keeping to document the location of all EPS blocks placed for the project. Note: A truckload of EPS blocks is intended to mean either a full-length box-trailer or a flat-bed trailer of typical dimensions, i.e., approximately 12 m (40 ft) 3 3 or more in length, fully loaded with EPS blocks. The volume of EPS in such a truckload would typically be on the order of 50 to 100 m (65 to 130 yd ).

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5 respects be the same as blocks to be supplied to the project, per cubic meter or pounds per cubic foot. Additional markings including required seasoning as described in Section 4.3. The using alphanumeric characters, colors, and/or symbols shall owner's agent will weigh, measure, sample, and test be applied as necessary by the supplier to indicate the location a random number of blocks to evaluate the ability of the of placement of each block relative to the shop drawing molder(s) to produce EPS-block geofoam of quality as spe- indicated in Section 6.5 of this specification, as well as the cified herein. The sampling and testing protocol will be the density of the block if multiple block densities are to be same as for Phase II MQA as discussed in Section 8. supplied for a given project. If multiple block densities/unit 6.5 If required by the contract documents, the contractor weights are to be supplied, the use of no marking shall be shall submit shop drawings indicating the proposed location considered an acceptable marking for one of the densities as and layout of all EPS blocks to be placed during the project. long as it is used for the lower (or lowest) density/unit weight When there are multiple molders, the areas to be covered by EPS blocks supplied to the project. each molder shall be clearly identified. These drawings shall 7.2 At all stages of manufacturing, shipment, and con- be reviewed by the owner's agent. The block layout shall struction, the EPS blocks shall be handled in a manner so as be designed so that the following general design details are to minimize physical damage to the blocks. No method of taken into account: lifting or transporting the blocks that creates dents or holes in the block surfaces or losses of portions of the block shall The plane on which a given layer of blocks is placed be allowed. must be parallel to the longitudinal axis of the road 7.3 If the EPS blocks are to be stockpiled at the project alignment. site until placement, a secure storage area shall be designated There must be a minimum of two layers of blocks at all for this purpose. The storage area shall be away from any heat locations. source or construction activity that produces heat or flame. In Within a given layer of blocks, the longitudinal axes of addition, personal tobacco smoking shall not be allowed in all blocks must be parallel to each other. the storage area. EPS blocks in temporary on-site storage Within a given layer of blocks, the vertical joints be- shall be secured with sandbags and similar "soft" weights to tween the adjacent ends of blocks within a given row of prevent their being dislodged by wind. The blocks shall not blocks must be offset to the greatest extent practicable be covered in any manner that might allow the buildup of relative to blocks in adjacent rows. heat beneath the cover. The blocks shall not be trafficked by The longitudinal axes of blocks for layers above and/or any vehicle or equipment. In addition, foot traffic by persons below a given layer must be perpendicular to the longi- shall be kept to a minimum. tudinal axes of blocks within that given layer. 7.4 EPS is not an inherently dangerous or toxic material, The longitudinal axes of the uppermost layer of blocks so there are no particular safety issues to be observed other must be perpendicular to the longitudinal axis of the than normal construction safety and protection against heat road alignment. and flame, as specified in Section 7.3. However, extra caution is required during wet or cold weather. Surfaces of the 6.6 Prior to delivery of any EPS-block geofoam to the EPS blocks tend to be more slippery when wet than when dry. project site, a meeting shall be held between, at a minimum, In addition, when air temperatures approach or go below the owner's agent and contractor. The supplier and/or molder/ freezing, a thin layer of ice can readily develop on the exposed RECOMMENDED EPS-BLOCK GEOFOAM STANDARD primary molder of the EPS-block geofoam may also attend surfaces of EPS blocks if the dewpoint is sufficiently high. at the contractor's discretion to answer any questions. The Thus, the surfaces of the EPS blocks can pose particular slip purpose of this meeting shall be to review the Phase I MQA hazards in this condition. results and discuss the Phase II MQA as well as other aspects of construction to ensure that all parties are familiar with the requirements of this standard. At the satisfactory conclusion 8 PRODUCT MANUFACTURING QUALITY of this meeting, the contractor shall be allowed to begin on- ASSURANCE: PHASE II site receipt, storage (if desired), and placement of the EPS- block geofoam. 8.1 Phase II MQA will be performed by the owner's agent as the EPS blocks are delivered to the project site. Phase II MQA will consist of four subphases (IIa through IId). The 7 PRODUCT SHIPMENT AND STORAGE contractor shall cooperate with and assist the owner's agent in implementing Phase II MQA. 7.1 Each EPS block shall be labeled to indicate the 8.2 Phase IIa MQA will consist of on-site visual in- name of the molder (if there is more than one supplying a spection of each block delivered to the project site to check for given project), the date the block was molded, the mass/ damage and to visually verify the labeled information on weight of the entire block (in kilograms or pounds) as each block. Any blocks with damage or not meeting specifi- measured after a satisfactory period of seasoning as specified cations will be (a) rejected on the spot and placed in an area in Section 4.3, the dimensions of the block in millimeters or separate from those blocks that are accepted or (b) marked inches, and the actual dry density/unit weight in kilograms "unacceptable" and returned to the supplier.

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6 8.3 Phase IIb MQA will consist of on-site verification that for the project. The contractor shall cooperate with and assist the minimum block dry density/unit weight, as well as the the owner's agent with this phase. physical tolerances specified in Sections 4.8 through 4.10, meets specifications. At least one truckload will be checked, and additional blocks will be checked if initial 9 CONSTRUCTION QUALITY measurements indicate lack of compliance. A truckload of REQUIREMENTS EPS blocks is defined as either a full-length box-trailer or a flat-bed trailer of typical dimensions, i.e., approximately 9.1 The contractor shall be directly responsible for all 12 m (40 ft) or more in length, fully loaded with EPS blocks. construction quality control (CQC). Items covered by CQC The volume of EPS in such a truckload would typically be on include all earthwork and related activities other than manu- the order of 50 to 100 m3 (65 to 130 yd3). The contractor shall facturing and shipment of the EPS-block geofoam. Items of supply a scale on site with sufficient capacity and precision particular relevance to the placement of EPS-block geofoam for weighing of EPS blocks. This scale shall be recently are given in Sections 10 through 12. calibrated, and certification of such calibration shall be made 9.2 The owner's agent will be responsible for providing available to the owner's agent. construction quality assurance (CQA) of the contractor's 8.4 Phase IIc MQA will consist of sampling the EPS construction activities. blocks and laboratory testing specimens prepared from these samples. Sampling will be at the locations shown in Figure 1. The laboratory tests will check for compliance with the 10 SITE PREPARATION parameters shown in Table 2. The contractor shall cooperate with and assist the owner's agent with obtaining the neces- 10.1 If required by the contract drawings, the natural soil sary samples. Testing will be by or under the direction of the subgrade shall be cleared of vegetation and any large or owner's agent. For each density/unit weight of EPS used on a sharp-edged soil particles and be reasonably planar prior to project, at least one block will be selected for sampling from placing a geotextile and/or sand bedding layer. If no sand the first truckload of EPS blocks of that density delivered to bedding layer is used, the natural subgrade shall be cleared the job site. Additional blocks may be selected for sampling such that there is no vegetation, or particles of soil or rock during the course of the project at the discretion of the owner's larger than coarse gravel, exposed at the surface. agent at a rate of sampling not to exceed one sample for every 10.2 Regardless of the subgrade material (i.e., natural 250 m3 (325 yd3) of EPS delivered. Portions of sampled blocks soils or sand bed), the subgrade surface on which the EPS that are otherwise acceptable can be used as desired by the blocks will be placed shall be sufficiently planar (i.e., smooth) contractor. The owner's agent will make every reasonable prior to the placement of the first block layer. The required effort to conduct the laboratory testing expeditiously. However, smoothness is defined as a vertical deviation of no more than if unsatisfactory test results are obtained, the contractor may 10 mm (0.4 in.) over any 3-m (9.8-ft) distance. be directed to remove potentially defective EPS blocks and 10.3 There shall be no debris of any kind on the subgrade replace them with blocks of acceptable quality at no additional surface when EPS blocks are placed. expense to the owner. 10.4 Unless directed otherwise by the owner's agent, 8.5 Phase IId MQA will consist of preparation of an there shall be no standing water or accumulated snow or ice RECOMMENDED EPS-BLOCK GEOFOAM STANDARD as-built drawing or drawings, as well as additional record on the subgrade within the area where EPS blocks are placed keeping to document the location of all EPS blocks placed at the time of block placement. Sample B L H C L A 2 4 W 4 H Test Specimen W 2 Top of Block (If Vertical Mold) or Fill L W End of Block (If Horizontal Mold) Figure 1. Recommended block sampling and test specimens.

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7 10.5 EPS blocks shall not be placed on a frozen subgrade 11.6 At no time shall heat or open flame be used near the except in the case of construction over continuous or dis- EPS blocks so as to cause melting or combustion of the EPS. continuous permafrost terrain and as directed by the owner's 11.7 The final surface of the EPS blocks shall be covered agent. as shown on the contract drawings. Care shall be exercised during placement of the cover material so as not to cause any damage to the EPS blocks. 11 PLACEMENT OF EPS-BLOCK GEOFOAM 12 PAVEMENT CONSTRUCTION 11.1 EPS blocks shall be placed at the locations shown on either the contract drawings or approved shop drawings sub- 12.1 The pavement system is defined for the purposes of mitted by the contractor. Particular care is required if EPS this standard as all material placed above the EPS blocks blocks of different density/unit weight are to be used on the within the limits of the roadway, including any shoulders. project. 12.2 The pavement system shall be constructed above the 11.2 EPS blocks shall be placed so that all vertical and EPS-block geofoam as shown on the contract drawings. horizontal joints between blocks are tight. Specifications covering construction of the pavement system 11.3 The surfaces of the EPS blocks shall not be directly are given elsewhere in the contract documents. traversed by any vehicle or construction equipment during or 12.3 No vehicles or construction equipment shall traverse after placement of the blocks. directly on the EPS blocks or on any separation material placed 11.4 Blocks shall not be placed above blocks in which ice between the EPS blocks and the pavement system. Soil or has developed on the surface. aggregate for the pavement system layers shall be pushed 11.5 With the exception of sand bags or similar "soft" onto the EPS blocks or separation layer using appropriate weights used to temporarily restrain EPS blocks against equipment such as a bulldozer or a front-end loader. A min- wind, no construction material other than that shown on the imum of 300 mm (12 in.) of soil or aggregate shall cover the contract drawings shall be placed or stockpiled on the EPS top of the EPS blocks or separation layer before compaction blocks. commences. RECOMMENDED EPS-BLOCK GEOFOAM STANDARD