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<br />, <br /> <br />3.2.2 The support and shoring systems shall be in accordance with the American Association <br />of State Highway and Transportation Officials (AASHTO), AREMA and Caltrans <br />requirements. The support and shoring system shall be designed to support all lateral <br />forces caused by the earth, railroad and other surcharge loads. The railroad loading to be <br />applied is a Cooper's E-80 loading. <br /> <br />3.2.3 When excavation is within the sheet piling zone [the area between the vertical line offset <br />8' -6" from the nearest track centerline and a one part horizontal to one part vertical (I : I) <br />projection, beginning at a point located 8'-6" from the nearest track centerline and 18 <br />inches below the bottom of the rail of the nearest track and sloping down and away from <br />the nearest track], interlocking steel sheet piling driven prior to excavation, must be used <br />to protect track stability. Steel sheet piling shall be abandoned in place, except for the <br />top three (3) feet, which shall be removed, backfilled. <br /> <br />3.2.4 When excavation is within the shoring zone [the area between a one part horizontal to <br />one part vertical (I: I) projection, beginning at a point located 8'-6" from the nearest <br />track centerline and 18 inches below the bottom of the rail of the nearest track and <br />sloping down and away from the nearest track and a one and half part horizontal to one <br />part vertical (1.5:1) projection, beginning at a point located II '-0" from the nearest track <br />centerline and 18 inches below the bottom of the rail of the nearest track and sloping <br />down and away from the nearest track], soldier pile system with lagging elements which <br />are placed as excavation proceeds can be used. <br /> <br />3.2.5 When excavation is within the excavation zone [the area that is located beyond a one and <br />half part horizontal to one part vertical (1.5:1) projection, beginning at a point located <br />II '-0" from the nearest track centerline and 18 inches below the bottom of the rail of the <br />nearest track and sloping down and away from the nearest track], shoring is not required <br />and sloping system is allowed. <br /> <br />3.2.6 Tiebacks or any other excavation support mechanisms that are installed under the track <br />structure shall be at least four (4) feet clear below top of the rail. <br /> <br />3.2.7 Support and shoring system drawings shall include plan view indicating the extent of all <br />proposed shoring relative to the nearest track centerline; cross-sections of all proposed <br />shoring cut perpendicular to the track and indicating track location with equal horizontal <br />and vertical scale; details of all structural members, connections and embedment depths <br />and impacted facilities including construction access locations, ditches mitigated <br />measures. Vertical dimensions shall be relative to the top of rail and horizontal <br />dimensions shall be relative to the nearest track centerline. <br /> <br />3.2.8 Prior to commencing the excavation of a trench five (5) feet in depth or greater and into <br />which a person will be required to descend, the Contractor shall first obtain a permit to <br />do so from the Division of Industrial Safety. Any excavation adjacent to track shall be <br />covered and ramped and provided with standard handrails. Handrails shall be in <br />accordance with the State of California Occupational Safety and Health Standards <br />(CALlOSHA) and CPUC General Order No. 26-0. <br /> <br />3.2.9 The face of all jacking and receiving pits shall be located a minimum of 25 feet from the <br />center line of the nearest track, measured at right angle to the track, unless otherwise <br />approved by SCRRA. The use of trench boxes may be permitted for jacking and <br />receiving pits, however, trench boxes are not acceptable within the sheet piling zone. <br /> <br />SCRRA/Metrolink <br />FORM37 <br /> <br />Page 5 <br /> <br />OS/27/04 <br />