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C0E â–º â–ºOriginally Issued: 02/11/2020 Valid Through: 02/28/2021
<br /> spacing between helical foundations (center to center of pile (HP288NCB or HP288NCB8)are embedded in new concrete
<br /> shaft) shall be a minimum of three times the diameter of the footings. Both bracket systems are connected to the helical
<br /> largest helix plate in adjacent helical foundations.For retrofit shaft to transfer the building load into the shaft.
<br /> applications, the foundation shaft shall be installed at an
<br /> angle of 2.5 ± 1.0 degree. For new construction pile 4.2 HP288 Lead and Extension Sections: The helical pile
<br /> installation,the foundation shaft shall be installed at an angle lead sections (HP288L) consists of a central steel shaft with
<br /> of± 1.0 degree from vertical. Adequate drainage shall be one or more factory-welded helix plates which are used to
<br /> provided where appropriate to direct water away from the transfer the load from the shaft to the appropriate soil bearing
<br /> foundation support locations. Where helical foundations are strata. Shaft extensions (HP288E) may also have factory-
<br /> installed in or adjacent to slopes, the negative effects of welded helix plates and are connected to the lead section or
<br /> drainage, erosion, and shallow failures shall be avoided in other extension sections with bolted coupling connections.
<br /> accordance with IRC Section R403.1.7. The extension sections are used as necessary to extend the
<br /> helical pile to the required bearing depth.
<br /> 3.3.2 Bracket Installation: Once adequate pile depth and
<br /> torsional resistance is reached, an appropriate cap or bracket The central steel shafts are produced from round,2.875-inch
<br /> shall be attached to transfer the supported load to the helical (73 mm) outer diameter by 0.276-inch(7 mm)nominal wall
<br /> foundation. For remedial foundation work, a retrofit bracket thickness hollow structural sections conforming to ASTM
<br /> (Figure 1) that imposes an eccentric load on the helical A500 Grade B or Grade C.The shafts have a minimum yield
<br /> foundations in accordance with design,may be used.For new strength of 60 ksi(413 MPa)and a minimum tensile strength
<br /> construction applications where the piles are concentrically of 70 ksi (483 MPa). One end of the extension sections
<br /> loaded and the pile caps are embedded in concrete, a new includes a factory-welded steel coupling and two steel
<br /> construction bracket (Figure 2), may be used. For tension coupling bolts for connecting the lead and extension sections
<br /> loads,the new construction bracket shall be through bolted to together. The lead and extension shaft finish is plain steel or
<br /> the helical pile shaft using the bolts and nuts specified in hot-dip galvanized in accordance with ASTM A123. The
<br /> Section 4.3. mechanical properties of the shaft under corroded or
<br /> uncorroded conditions,as described in Section 2.7,with plain
<br /> 3.4 Field reports: A helical foundation installation log shall steel or hot-dip galvanized coating are included in Table 1.
<br /> be prepared describing the installation results and the soil
<br /> axial capacities shall be determined from the installation data 4.3 Couplings: The HP288 extension shaft includes a
<br /> in accordance with Section 3.2.4. Installers shall record all factory-welded,round,outer steel,coupling sleeve consisting
<br /> helical foundation locations and types including shaft of a 6-inch-long(152 mm),31/2-inch-OD (89 mm)by 0.281-
<br /> diameters,helix sizes and configurations,embedment depths, inch (7.14 mm) nominal wall thickness, hollow structural
<br /> pile lengths and final torque readings. In addition, a torque section.The coupling sleeves conform to ASTM A513,Type
<br /> profile shall be recorded for every project, and at least one 5, Drawn over a Mandrel (DOM), Grade 1026 having a
<br /> out of every ten piles in multi-pile installations. minimum yield strength of 70 ksi(483 MPa)and a minimum
<br /> tensile strength of 80 ksi(552 MPa).Each coupling includes
<br /> A field report containing this information,along with the type two standard hex bolts and matching standard hex nuts. The
<br /> of project,relevant details of the supported structure, sketch bolts are 1/4-10 UNC 2A standard hex bolts conforming to
<br /> or drawing of the support locations with dimensions, the SAE J429,Grade 5,with a minimum yield strength of 92 ksi
<br /> types of helical foundation brackets used at each location and (634 MPa) and a minimum tensile strength of 120 ksi (827
<br /> information related the connection of the brackets to the MPa). The matching nuts are 3/4-10 UNC 2B standard hex
<br /> helical shaft and the supported structure,allowable soil axial nuts conforming to SAE J995, Grade 5. The bolts and nuts
<br /> capacity based on torque-to-capacity ratio,and other relevant are zinc-coated in accordance with ASTM B633,with coating
<br /> notes and comments as needed,shall be reviewed and sealed classification Fe/Zn 8.
<br /> by a registered design professional. The report shall be
<br /> submitted to the building official for approval within 10 days 4.4 Helix Plates: The helical bearing plates have a standard
<br /> after helical foundation installation. pitch of 3 inches (76 min), are 0.375 inch (9.53 mm) thick,
<br /> and are made from ASTM A572 Grade 50 steel plate material
<br /> 4.0 PRODUCT DESCRIPTION having minimum yield strength of 50 ksi (345 MPa) and
<br /> minimum tensile strength of 65 ksi (448 MPa). The helix
<br /> 4.1 General:The Supportworks helical foundation system is plates are available in diameters of 8, 10, 12, and 14 inches
<br /> a steel foundation assembly consisting of a lead shaft, shaft (203 nun, 254 mm, 305 mm, or 356 mm) and are factory
<br /> extensions,and a retrofit bracket or new construction bracket. welded to the shafts in accordance with the manufacturer's
<br /> The retrofit bracket(FS288BL2)is secured against and below quality control documentation. The helix plate finish is plain
<br /> existing footings and the new construction brackets
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