General purpose, non-shrink, cementitiousmicroconcreteUses
|Packaging Type||HDPE Bag|
|Shelf Life||6 Months|
For economical repairs to damaged reinforced concrete
elements, particularly where access is restricted and where
vibration of the placed material is difficult or impossible.
Suitable for various structural strengthening measures such
as filling honeycombs and cracks.Advantages
Gaseous expansion system compensates for shrinkage
and settlement in the plastic state.
Can be pumped or poured into restricted locations.
Highly fluid to allow for placement without vibration.
Pre-packed to overcome site-batched variations.
Economical Contains no chloride admixture. Ease of useDescription
Renderoc RG(L) is supplied as a ready to use blend of dry
powder, which requires only the site addition of clean water
to produce a free-flowing, non-shrink microconcrete. The
material is based on Portland cements, and fillers, and
additives which impart controlled expansion characteristics
in the plastic state, while minimising water demand. The low
water requirement ensures high early strength and long-term
For larger repairs, Renderoc RG(L) may be modified by the
addition of 5mm to 12mm clean, graded saturated surface
dry aggregates at site. For exceptionally large repairs, the
local Fosroc office should be consulted.Specification clauses
The fluid micro-concrete microconcrete shall be Renderoc
RG(L), a single component, cement-based material to which
only the site-addition of clean water (and approved graded
coarse aggregates where specified) shall be permitted. The
repair grout in the flowable consistency should achieve a
compressive strength of not less than 8N/mm2 after 24 hours
at 300C. Most importantly, the cured micro concrete shall
contain no metallic aggregates, or chlorides and shall be
shrinkage compensated in the plastic state. The micro
concrete shall have a coefficient of thermal expansion similar
to that of the host concrete.Application instructions
The unrestrained surface area of the repair must be kept to a
minimum. The formwok should include drainage outlets for
pre-soaking and, if beneath a soffit, provision for airventing.
Provision must also be made for suitable access points to
pour or pump the mixed micro-concrete in place.
Defective concrete surfaces must be cut back to a sound base.
Smooth surfaces should be mechanically roughened.
Corroded reinforcing steel should be exposed around its full
circumference and cleaned to remove all loose scale and
corrosion deposits. It is important to clean the steel to a bright
condition. Grit-blasting is recommended.
One coat of Nitozinc Primer should be applied on the reinforcing
Mixing Care should be taken to ensure that Renderoc RG(L) is thoroughly mixed in a forced-action mixer of adequate capacity. Alternatively, mix in a suitably sized drum with a high torque ( 400/500 rpm) rotary drill fitted with a mixing paddle. It is essential that machine mixing capacity and labour availability is adequate to enable the placing / pumping operation to be carried out continuously. The quantity water required will generally be between 4.5 and 4.75 litres per 25 kg bag of Renderoc RG(L). The optimum water content should be determined and accurately measured into the mixer. However it should not exceed 4.75 litres / 25 kg in any case. With the mixer running, slowly empty Renderoc RG(L) bag into the mixer. Mix continuously for 5 minutes, ensuring a smooth even consistency of the mix Where the addition of graded coarse aggregate has been specified it should be added after the water and Renderoc RG(S) are properly mixed.