Closed insulation system
It is important for the bands to form a closed insulation system, and for their free ends to be routed to at least 30 cm above the highest water level stemming from site observations. In case of basins and low points, the highest water level is the maximum projected fill level foreseen for a given structure.
If the building is divided by expansion joints, then all compensation hoses at the free ends of bands should be protected (closed) by a mass allowing adaptation to their shape, and the slits above should be protected using appropriate resources.
One should take particular care that:
If a passage is made between bands of different widths, the joint between them has to be made in the same way so as to maintain anchor continuity. Trimming bands, angles and changes of concreting levels of bands in day joints and expansion joints should, if possible, run at straight angles.
Minimum bend angle
When installing sealing bands, one often has to face the task of adapting their course to the altering form of the division to be protected. In order to avoid bends in sealing anchors, which could cause imprecise filling of the concrete mix around the band, one should adhere to the following bend angles:
The most obvious sealing band arrangement around a circular shape or circle section is the execution of components or structures with circular shapes. if the recommended bend angle radius cannot be adhered to, one should manufacture a pre-cast joining component, manufactured at a plant by a manufacturer or at the construction site by specialist installation teams.
In order for sealing bands to properly fulfil their roles, they must be concreted appropriately. According to indications of standard DIN 18197 'Sealing of joints in concrete with waterstops', between the sealing band and the steel reinforcement a distance of ≥ 20 mm must be maintained. The designed must, when beginning his work, reach a decision concerning the appropriate material for and type of band (internal, external, closing) together with appropriately designing the component reinforcement structure.
Only when designing a joint of the foundation slab with the wall, one may use internal bands without interfering in the reinforcement. in such a case, it is required that a threshold be made on the slab in order to embed the band. Such an addition should be made during concreting of the slab and not as an additional part. The use of Bestal steel mesh as stay-in-place formwork greatly simplifies this task.
|Use of an internal sealing band for day joints||Use of Bestal day joint bands|
|Use of type Kab sealing bands with swell profiles|
Allowable deformation vector
In order to select a sealing band for expansion joints, one has to know the shearing and cutting movements that will attempt to tear the installed band. When calculating the deformation, one should consider all deformations in directions x, y and z that may emerge during construction as well as during use. One may use the following formula to describe them:
Selection of pressure and the determination of technical parameters of installation components for bands for mechanical mounting (using compression structures)
When faced with the dilemma of having to construct a tight solution of a joint between a newly-designed structure with an existing part, or with installation of bands in complex structures, where the band is supposed to provide protection at an intersection between a concrete structure with a building's steel components, the use of mechanical assembly of bands using a compression system with a flange is both economical and appropriate in order to achieve tightness.
The selection of an appropriate sealing band, flat profiles, anchors, compression bolts and supplementary equipment should be preceded by a thorough design analysis. Having selected an appropriate band, one should determine the width and dimensions of the compression structure and the spacing and size of tension anchors. When using all the above named system components, one needs to provide a value for pressure of the band on the concrete that would be higher than the water pressure acting on the joints.
The above information applies only to standard situations!!!
Sealing band selection diagrams
One should keep in mind that the option of using sealing bands is determined by the value of movements in the area of the division to be protected, the pressure exerted by the water acting on the band and the aggression level of the substances dissolved in the water. In order to appropriately select our products, the following diagrams show relations (scope of shift movements - water column pressure) for the individual sealing band types.
The scope of these structure shifts must be greater than or equal to the vector of allowable deformation (Vr) of the band, calculated using the formula:
|Besaflex type D||Nitriflex type D|
|Elastoflex type FM||Elastoflex type FMS|
|Besaflex type AD||Besaflex type FV|
|Nitriflex type DA||Nitriflex typeFA|
|Elastoflex type AM||Elastoflex type FAE|