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• Attention is directed to the provisions in Section 7-1.09, "Public Safety." Whenever a portion of an assemblage of <br /> bar reinforcing steel that is not encased in concrete exceeds 6 in in height, the Contractor shall submit to the Engineer for <br /> approval,in accordance with the provisions in Section 5-1.02, "Plans and Working Drawings,"working drawings and design <br /> calculations for the temporary support system to be used. The working drawings and design calculations shall be signed by <br /> an engineer who is registered as a Civil Engineer in the State of California. The temporary support system shall be designed <br /> to resist all expected loads and shall be adequate to prevent collapse or overturning of the assemblage. If the installation of <br /> forms or other work requires revisions to or temporary release of any portion of the temporary support system, the working <br /> drawings shall show the support system to be used during each phase of construction. The minimum horizontal wind load to <br /> be applied to the bar reinforcing steel assemblage, or to a combined assemblage of reinforcing steel and forms, shall be the <br /> sum of the products of the wind impact area and the applicable wind pressure value for each height zone. The wind impact <br /> area is the total projected area of the cage normal to the direction of the applied wind. Wind pressure values shall be <br /> determined from the following table: <br /> Height Zone Wind Pressure Value <br /> Meters above M22Ldj Pa <br /> 0-9.0 960 <br /> 9.1-15.0 1200 <br /> 15.1-30.0 1440 <br /> Over 30 1675 <br /> Section 52-1.08 "Splicing,"of the Standard Specifications is amended to read: <br /> 52-1.08 SPLICING <br /> • Splices of reinforcing bars shall consist of lap splices,service splices,or ultimate butt splices. <br /> • Splicing of reinforcing bars will not be permitted at a location designated on the plans as a "No-Splice Zone." At <br /> the option of the Contractor, reinforcing bars may be continuous at locations where splices are shown on the plans. The <br /> location of splices, except where shown on the plans, shall be determined by the Contractor using available commercial <br /> lengths where practicable. <br /> • Unless otherwise shown on the plans,splices in adjacent reinforcing bars at any particular section shall be staggered. <br /> The minimum distance between staggered lap splices or mechanical lap splices shall be the same as the length required for a <br /> lap splice in the largest bar. The minimum distance between staggered butt splices shall be 600 mm,measured between the <br /> midpoints of the splices along a line which is centered between the axes of the adjacent bars. <br /> 52-1.08A Lap Splicing Requirements <br /> • Splices made by lapping shall consist of placing reinforcing bars in contact and wiring them together, maintaining <br /> the alignment of the bars and the minimum clearances. Should the Contractor elect to use a butt welded or mechanical splice <br /> at a location not designated on the plans as requiring a service or ultimate butt splice,this splice shall conform to the testing <br /> requirements for service splice,. <br /> • Reinforcing bars shall not be spliced by lapping at locations where the concrete section is not sufficient to provide a <br /> minimum clear distance of 50 mm between the splice and the nearest adjacent bar. The clearance to the surface of the <br /> concrete specified in Section 52-1.07,"Placing,"shall not be reduced. <br /> • Reinforcing bars Nos. 43 and 57 shall not be spliced by lapping. <br /> • Where ASTM Designations: A 615/A 615M,Grade 420 or A 706/A 706M reinforcing bars are required,the length <br /> of lap splices shall be as follows: Reinforcing bars No.25 or smaller shall be lapped at least 45 diameters of the smaller bar <br /> joined; and reinforcing bars Nos.29,32, and 36 shall be lapped at least 60 diameters of the smaller bar joined, except when <br /> otherwise shown on the plans. <br /> • Where ASTM Designation: A 615/A 615M,Grade 280 reinforcing bars are permitted,the length of lap splices shall <br /> be as follows: Reinforcing bars No.25 or smaller shall be lapped at least 30 diameters of the smaller bar joined; and <br /> reinforcing bars Nos.29, 32, and 36 shall be lapped at least 45 diameters of the smaller bar joined, except when otherwise <br /> shown on the plans. <br /> • Splices in bundled bars shall conform to the following: <br /> A In bundles of 2 bars,the length of the lap splice shall be the same as the length of a single bar lap splice. <br /> B. In bundles of 3 bars,the length of the lap splice shall be 1.2 times the length of a single bar lap splice. <br /> • <br /> of: Welded wire fabric shall be lapped such that the overlap between the outermost cross wires is not less than the larger <br /> - <br /> Contract No. 10-OM7104 <br /> 35 <br />