Installation Instructions Stationary Weighpad_ELWC - WIM

It is possible for water to penetrate into the frame or under installed weighpads.
This leads to false axle load measurements, especially in the winter when water
freezes under the weighpads. Therefore, it is necessary to install a drain pipe
at the lowest point of the frame recess. The drain should be 2"–4" (5 cm - 10
cm) diameter and sloping into a french drain, water shaft or culvert.
Figure 1 - Drainage Styles
The roadway is part of the WIM system and therefore must be as flat and
uniform as possible for approximately 200' (60 M) before and 50' (15 M) after
the weighpad. For increased accuracy requirements, evenness must meet
ASTM1318 specifications, at a minimum must not exceed 1/10" (0.25 cm) in 13'
(4 M).
ASTM 1318 requires a stretch of 150' before and 150' after the scale to be level
within the evenness tolerance. IRD-PAT Traffic only requires a 50' stretch after
the scale, but 200' before the scale to be level.
Vehicles to be measured must be able to pass over the weighpads without
accelerating or braking.
The entire measuring distance must be straight, with no curves or grades. The
longitudinal slope must not exceed 3% for statistical traffic data registration or
1% for weighstations. A transverse slop of approximately 1% at weighstations
is desirable to avoid hydroplaning.
Wheel grooves existing in the measuring area must be removed.
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M&E Vendor Documents
Control Systems
Section 9.11.3
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