Laserfiche WebLink
16 <br /> <br />4.4.1 Installing Standard Steel Guardrail Posts #3 and Beyond <br /> <br />All posts at locations #3 and beyond are W6x9# or W6x8.5# x 6'-0" long standard steel guardrail <br />posts spaced at 6'-3" centers. Blockouts are 8" or 12". The finished guardrail height should be <br />approximately 31"  1" above the edge of the shoulder or the finished grade. <br /> <br />For the MSKT, if the pay limit for the system is 50'-0" long, posts #3 - #8 will be standard steel <br />guardrail posts. See Figure 1. <br /> <br />The acceptable pay limit lengths are described under the General Information section on pages 2 <br />and 3. NOTE: The MGS barrier requires mid‐span splices between posts.   Pay limits of the  <br />terminal often vary by 3'‐ 1½" (depending on rail lengths).  See page 4 for allowable rail lengths  <br /> and pay limits. <br /> <br />4.4.2 Installing Breakaway Steel End Posts #1 and #2 <br /> <br />Posts #1 & #2 are hinged steel posts. These bolted posts must have the lower section installed <br />before attaching the top section. Be sure an adequate driving cap is used so the welds on the cap <br />plate of post #1 and the welds on the side plates of post #2 are not damaged. The lower section of <br />the bolted hinged steel posts should not be driven with the upper post attached. Posts #1 & #2 are <br />spaced at 6'-3" centers. <br /> <br />Upper and lower Post #2 are W6x9# or W6x8.5#sections. Bolt upper and lower post #2 together <br />with a ¾" x 8 ½" hex bolt and nut. A ¾" washer is not needed but may be used. One end of the <br />ground strut will be placed here. Be sure when the lower segment of the post is installed, the <br />hinge bolt is on the downstream side of the post (opposite the impact head). Upper post #2 has an <br />open-ended slot for the post bolt. If there are two slots, the top slot will be used to achieve the <br />31" rail height. Be sure slot is on the upstream side of the post (toward the impact head). See <br />Figure 5 for post #2 details. <br /> <br />Upper Post #1 is a 6" x 6" x ⅛" tube section. The post will be placed so the angle spacer is facing <br />oncoming traffic. The bearing plate will rest on this angle spacer. Lower Post #1 is a W6x15# <br />post with a soil plate welded to the post. Bolt upper and lower post #1 together with a ⅝" x 9" <br />hex bolt, nut and washer. Be sure when the post is installed, the hinge bolt is on the upstream side <br />of the post (toward the impact head). One end of the ground strut will be placed at post #1 against <br />the extended side plates, not the post itself and will use another hex bolt. Be sure when the lower <br />segment of the post is installed, the soil plate is on the downstream side of the post (opposite the <br />impact head). See Figure 4. <br /> <br />The top of the lower post #1 & #2 stubs should not project more than 4 above the ground line <br />when measured along a 5' cord, in compliance with AASHTO specifications. Site grading may be <br />required if the top of the lower post section project more than 4" above the ground line. <br /> <br />For stiff soils, drill a pilot hole and force the post to the proper depth by impact or vibratory <br />means with an appropriate driving cap. For post #1, be sure the driving cap is on top plate and not <br />the side plates. Do not drive on the side plates of lower posts #1 & #2 as they may be damaged. <br /> <br />The post may also be installed by augering and backfilling if the contractor so prefers. The initial <br />hole must be large enough to allow adequate room for proper compaction of the soil during <br />backfill. Care must be taken to carefully compact the backfill to prevent settlement or lateral <br />displacement of the post. If rock is encountered during driving or excavation, refer to appropriate <br />State specifications for how to proceed or contact Road Systems, Inc.