Page 60 - 2018 DIGITAL BROCHURE
P. 60

SHOTCRETE 430F





            Method of use                                                      Application



            Preparing the surface             Mixing                           General
            Do not use on frozen or over      For optimum results mix using    A 35mm minimum thickness of
            heated substrates (outside the    conventional dry spray mixing    the material is always necessary.
            range of 0°c-30°c). Prepare the   machines. The optimum water      Once setting has started DO NOT
            surface in advance to provide an   to cement ratio of 38% should   attempt to remix or to smooth
            adequate key. It should be clean,   be aimed for. Exceeding this   the surface. This will cause the
            free from dust and thoroughly     ratio will lead to lower strength,   mechanical properties in particular
            dampened. Where necessary         longer setting time and the risk   strength and adhesion to be lost.
            steel or aluminium mesh can be    of surface cracking appearing.   Do not premix SHOTCRETE 430F
            used. Ensure that a 35mm          SHOTCRETE 430F should be         with water before placing in the
            minimum thickness of material is   added to the dry spray shotcrete   dry spray machine.  Protect the
            obtained.                         machine and transported by dry   surface of the SHOTCRETE 430F
                                              air to the nozzle where the water   from direct sunlight or wind until
            Priming                           is added. To obtain low dust     setting has completed. Once the
            There is no need to prime any     levels, better and more consistent   SHOTCRETE 430F has set allow
            reinforcement, but if priming is   mixing qualities it is advisable   at least 1 hour before applying
            preferred, any conventional       that the water is added to the   any finishes.
            system may be used.               SHOTCRETE 430F approximately
                                              1.5 metres from the end of the   Carry out the removal of all loose
                                              nozzle. In cold weather the set   material from the concrete and
                                              can be accelerated using warm    reinforcement. It is only
                                              water, likewise in hot weather cold   necessary to remove rust from
                                              water can be used to slow down   the reinforcement. Prepare the
                                              the set.                         surface as described previously,
                                                                               ensuring the surface is well
                                                                               dampened but also ensuring there
                                                                               is no standing water. Fix any
                                                                               necessary reinforcement,
                                                                               movement joints and formwork.
                                                                               Add the dry SHOTCRETE 430F
                                                                               powder continuously to the dry
                                                                               spray applicator machine with the
                                                                               water being added and controlled
                                                                               at the nozzle ensuring that the
                                                                               SHOTCRETE 430F is worked
                                                                               around any reinforcement.
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