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Micro concrete

Micro Concrete is a flowable mortar for repairs to damaged reinforced concrete
members. The quantity of aggregate which can be incorporated may be limited by
the method of placing. If a simple pouring technique is used, 10 m aggregate may
form 50% of the total dry materials, but if pumping is preferred the aggregate size
and quantity will need to be reduced to suit the limitations of the pump.

When the repair section exists in only one plane, i.e., a simple vertical section,
it is sufficient to pour the material in from the top of the shutter, it will not suffer
the severe segregation which occurs with normal concretes.

If the repair is more than 1.5 m wide it is advisable to have two pouring points
being fed simultaneously. It is also necessary to consider venting the top of the cavity if
it is enclosed.  shows the placing of superficial micro concrete in a vertical section.

                                       Placing of superficial micro concrete in a vertical section

If repair is to a soffit the supply arrangements will be quite different. If it is the
the soffit is to a moderately thin slab, it may be possible to drill feed holes and vent
holes right through the slab. If the area exceeds 1.5 m2 it would be wise to have a
second feed hole. The material should not be poured directly down the holes but
through a loose-fitting PVC pipe, a rainwater pipe say 50 mm or larger, extending
0.5 m above the top of the void as shown in Fig.

                                         Placing of superficial micro concrete to a soffit

Properties are

  1. ·        Can be pumped or poured into restricted locations.
  2. ·        Flowable mortar hence does not require compaction.
  3. ·        Gaseous expansion system compensate for shrinkage and settlement in the plastic state
  4. ·        Develops high initial and ultimate final strengths.
  5. ·        Offers excellent resistance to moisture ingress.
  6.  .      Can be applied at 100 mm thickness at one stroke

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