Trinity 620005, Инструкция по сборке

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TrinityHighway.com 15 Revision F November 2021
Ground Preparation and Barrier Alignment
CASS
®
S3 shall be placed on a median or roadside without obstructions, depressions, etc. that
may significantly affect the stability of an errant vehicle. Grading of the site and/or appropriate fill
materials may be required. The assembler shall “flatten” or “round” various topographical
inconsistencies that could interfere with the ability to consistently maintain the design height (in
relation to the terrain) of the cables. To address assembly in rock, see Appendix C: Encountering
Rock.
Warning:
It is imperative, before assembly, that you contact a Trinity Highway
representative and state/specifying agency engineer for special criteria involving
soil conditions not meeting or exceeding NCHRP Report 350 soil conditions. It is
also recommended that you consult your own soils or structural engineer.
Note: Based on soil conditions at the site, ANY or ALL foundations may need larger/deeper
concrete footings or larger soil plates (for driven applications) as determined by soil analysis.
Ground Preparation
When CASS
®
S3 is placed in a median, use the following criteria for locating the system:
Ensure that the finished grade (side slope) is 1V:4H or flatter.
When the NCHRP Report 350 CASS
®
S3 is placed on a ditch section and the
side slope is 1V:4H or flatter; but, steeper than 1V:6H, the maximum offset
from the hinge point is 4’ [1.3 m] and minimum offset from the bottom of the
ditch is 11’ [3.3 m]. According to FHWA and AASHTO, on side slopes
steeper than 1V:10H, the cable median barrier (including CASS
®
S3) cannot
be placed within 1’ to 8’ [0.3m to 2.4 m] from the ditch line.
When the MASH CASS
®
S3 is placed on a ditch section and the side slope
is 1V:4H or flatter; but steeper than 1V:10H, the maximum offset from the
hinge point is 4’ [1.3 m] and minimum offset from the bottom of the ditch is
11’ [3.3 m].
When the side slope is 1V:10H or flatter, CASS
®
S3 can be placed
anywhere in the median.
Barrier Alignment
Follow all procedures in the placement of the footing and/or post to ensure proper alignment. It
is suggested that a string line or other means be used to provide a consistent horizontal and
vertical alignment that meets specifications. If assembled on a horizontal curve, a minimum 650
foot [198 m] radius is required. If assembled on a
sag vertical curve , the K value is ≥ 100’ [30
m]. See “Assembly on a Curve” Section.
CASS
®
S3 can be placed on the roadside in front of slopes 1V:2H or flatter. Use a minimum
distance of 2’ [0.6 m] in front of the hinge point to the center of the post.
Use the state/specifying agency or agency’s guardrail terminal standards for grading and
widening for the CCT.
There may be instances where a break will be required in the cable run. In these circumstances
proper overlap of the terminals is required in order to prevent a vehicle from passing through the
protected area. Depending on the location of the cable with respect to the direction of traffic, there
are two situations which can occur. See Appendix B for recommended overlaps.