General Information

General information

Singular continued concreting of reinforced concrete walls and walls of water tanks at long sections, however, requires certain knowledge of the properties of concrete and later rheologic influence on the behaviour of the entire structure. In terms of structure tightness, however, very important are additional concrete deformations that take place during the use of the structure, occurring due to concrete contraction and creep.
By virtue of complexity of rheologic effects and complicated mathematical procedures, as well as numerous assumptions of the threshold state to be made during the calculation of these parameters, they are often neglected in terms of strength calculations for structures. In such cases, the designer's role is often limited to including maximum expansion joint spacings in the design, indicating the minimum reinforcement field and the guidelines to be fulfilled with respect to concrete layout and care.
Engineering practice shows, however, that such means are not always sufficient. The result is wearing of shields. The difficulty of achieving good seals, and sometimes of indicating of the proper leak spots, the emerged cracks, may reduce the usability of a structure and greatly increase its usage costs. From the practical standpoint, the following is worth quoting:
'Prevention is better than cure' with respect to repair of cracked shields. Seeking to limit uncontrolled reinforced concrete wall fractures, one available solution is weakening of the wall cross-section through creation of precisely positioned vertical cracks. The use of Besaflex type S induced crack piping additionally protects the created crack from penetration by pressing water using the labyrinth effect.

Properties Unit
Requirements Tested per 
External form -
No cracks, rifts Visual evaluation
Shore hardness ˚Sh
83±5
PN-EN ISO 868:2005
Stretch resistance MPa
≥ 9
PN-EN ISO 527-2:1998
Relative elongation at break %
≥ 200
PN-EN ISO 527-2:1998
Shear resistance N/mm
≥ 8
PN- ISO 34-1:2007
Low temperature behaviour, -20 ˚C,
relative elongation at break
%
≥100 PN-EN ISO 527-2:1998

 

 

Controlled crack inducer pipe
Symbol
a
[mm]

d
[mm]
f
[mm]
Wall width
[mm]

Package
[pcs./pallete]
Sales
unit

Weight
[kg/mb]
Art. no.
Type S1 L=3 m
128 88 25 240÷350 100 pcs. = 3m
2,80 SU-TU-RR-0-02357
Type S1 L=4 m pcs. = 4m
SU-TU-RR-0-02358
Type S1 L=5 m 
pcs. = 5m
SU-TU-RR-0-02359
Type S2 L=3 m
235 175 25 350÷500 50 pcs. = 3m
5,50 SU-TU-RR-0-02360
Type S2 L=4 m
pcs. = 4m
SU-TU-RR-0-02361
Type S2 L=5 m
pcs. = 5m
SU-TU-RR-0-02362
Type S2 L=7 m
pcs. = 7m
SU-TU-RR-0-02363
Type S3 L=3 m
110 60 25 170÷240 120 pcs. = 3m
2,00 SU-TU-RR-0-02364
Type S3 L=4 m
pcs. = 4m
SU-TU-RR-0-02365
Type S3 L=5 m
pcs. = 5m
SU-TU-RR-0-02366

 

Usage

Besaflex type S controlled induced crack pipes should be used at sites under threat of influence of liquids under hydrostatic pressure or of groundwater, for which the formwork or concreting technology requires the works to be carried out along large wall sections. The induced crack pipe selection depends on the thickness and height of the component to be weakened. No joined pipes should be used, and no piping composed of short sections should be used either. The axial separation of the selected controlled induced crack pipes depends on the following formula:

where:
R - axial pipe spacing,
h - height of component to be weakened,
g - component thickness.