Development and manufacturing of non-
destructive testing units and system
Ultrasonic Tester of Building Materials Strength NOVOTEST IPSM-U
21
where,
l
– measurement base through a crack in the concrete (the position
of the probes B-P1), the crack is located exactly in the middle, and
the time of spreading waves
– t
1
;
а
– measurement base on "clean" concrete - without defects (the
position of the probes B-P2), provided always a = l, and the time of
spreading waves
– t
а
.
According to the procedure adopted in the United Kingdom
(standard
BS 1881 р.203) is used difference scheme of installation
the probes:
