ENGINEERING YOUR SAFETY
WWW.HIGHWAYCARE.COM
Rev. C
–
10/18
©2018 Highway Care Limited. All Rights Reserved.
Page
10
of
61
Calculated Deflections
Reduced safty zone data tables shows
calculated deflections in metres at various
performance levels for BG800 when anchored
as per system setup: (These calculations have
been based on actual test data).
The normalised deflections have been
calculated using the formula contained in the
extract from EN1317 part 2 UAP document
below.
Note: The actual and normalised values of dynamic
deflection and working width shall be measured
and recorded in the test report.
Normalised Dynamic Deflection: D
N
(m)
(
)
(
)
2
2
M
M
M
T
T
T
M
N
Sin
V
M
Sin
V
M
D
D
=
Normalised Working Width: W
N
(m)
N
M
M
N
D
D
W
W
+
−
=
Where:
•
Measured Maximum Dynamic Deflection: D
M
(m)
•
Measured Working Width: W
M
(m)
•
Test Total Mass: M
T
(kg)
•
Test Velocity: V
T
(m/s)
•
Test Angle: θ
T
•
Measured Test Total Mass: M
M
(kg)
•
Measured Test Velocity: V
M
(m/s)
•
Measured Test Angle: θ
M
We can calculate the expected deflections of the
systems when impacted at slower speeds and
shallower impact angles using an EN1317
formula. These deflections are shown on the
systems pages in tables and can be used for
justifying reduced safety zones, when restricted
by site specific restraints.
