HARD TOP-70

General

HARD TOP-70 is a ready to use, non-metallic, floor and surface hardening agent based on very hard natural aggregates. It is to be applied by dry shake method in two operations; on freshly floated concrete or compensatory mortar toppings. The application of HARD TOP-70 provides wear-resistance to concrete surfaces thereby extending the service life of industrial, commercial, and residential floors. The floors are rendered tough, wear resistant, dust free, physiologically harmless and above all durable and maintenance free. HARD TOP-70 is an unique combination of selected cementatious binder modified by polymers, to impart the mix plasticity and high strength, blended with well-graded cubical natural hard aggregates. The grading is most critical and ensures maximum possible surface density. When applied HARD TOP-70 provides a denser surface with lower permeability coupled with increased wear and impact resistance. HARD TOP-70 bonds monolithically to the base concrete and is suitable for old as well as new floorings and surfaces. The greatest advantages of HARD TOP-70 over conventional metallic hardeners is the non-rusting property which enables its use in wet rooms as well as for outdoor applications. HARD TOP-70 floors are able to withstand almost all types of mechanical stresses such as rolling, sliding, percussion, impact, abrasion etc. HARD TOP-70 surfaces are very economical compared to alternative possibility with epoxy and other liquid plastics.

Advantages

HARD TOP-70 surfaces acquire following exceptional properties:

• Highly wear and abrasion resistant toppings, which are non-dusting. About twice abrasion resistant compared to normal concrete floor. Suitability for interior and exterior applications.
• Non-slip and anti-skid even in cases of oil spillages. High density and requiring minimum maintenance
• Not electrostatically chargeable. Physiologically harmless and easy to clean. Resistant to petrol, mineral oils etc. Waterproof – suitable for constantly wet rooms and exteriors. Suitable for old floors, new floors and repairs. Increased serviceable life and therefore economical

Fields Of Application

HARD TOP-70 can be employed everywhere, where an economical, durable surface or floors are desired under several mechanical stresses. HARD TOP-70 surfaces are of highest dimensional stability and wear resistant, which makes the material suitable for application in industries like automobile industry, aircraft engineering, foundries, dairies, tanneries, breweries, chemical plants, electrical industry, power plants, food industry, pharmaceutical plants printing presses, public buildings, metallurgical industry, military and ammunition factories, slaughter houses, steel mills etc. It is suitable for toppings and floorings of:

• Workshops, shop floors and production areas, Exhibition halls, stadiums, railway platforms and staircases for public utilities buildings, Production assembly storage halls and warehouses, Roadway surfacings, road repairs, runways and loading areas, Loading and unloading rafts and bays, Paper stores, bunkers and courtyards used by traffic
• Civil engineering structures and hydraulics, airport construction and passage-ways, Ice skating rinks and other skating areas and sport places, Suitable for normal applications as well as vacuum dewatering process applications
• Shopping centres, hotels, hospitals, schools etc, Grain silos and other silos storing abrasive material, All areas subjected to heavy wear, tear, rolling and impact. Hard toppings for any indoor or outdoor floor installations
• Hangars, shipyards, car ramps and part places

Types Of Applications

HARD TOP-70 is suitable for application on both old floors and new floors. Joints should be paid proper attention in both the cases as per standard norms of provision of joints. The application varies in both the cases as under:

• Existing Concrete Floors – By using a compensating layer.
• Newly Cast Floors – Monolithic construction

In the first case, i.e. Existing Concrete Floors, the base concrete should be sound, clean and free from oils and other contaminations to ascertain the proper bonding of the compensating layer. The existing surface should be wetted for about 24 hours prior to beginning of the new work. First a slurry coat should be applied on the prepared base. Slurry can be either of ready to use polymer mortar BONDFIT-8000 POWDER with HIGH BOND 40 or a mixture of cement-sand (1:2) prepared with HIGH BOND 40 admixed water (HIGH BOND 40 : WATER = 1:3). The further compensating layer should be about 25-50 mm thick consisting of cement to aggregates 1:3 (50% 4-8 mm and 50% 0-4 mm). Cement content should be at least 400 kg per cu.m. and water – cement ratio between 0.45 – 0.50.

This layer should be well compacted. HARD TOP-70 can be broadcasted immediately following the initial set. In case of newly cast floors, the concrete should be cast as per the prevailing good concrete practice. The cement content should be minimum 300 kg/cu.m. and water-cement ratio should be so adjusted to obtain a concrete of minimum 28 days strength of 30 N/sq.mm. A high early strength super-plasticizer like STANRO SP-1 can be incorporated if the above values are difficult to be obtained. The bleeding water should evaporate and HARD TOP-70 can be broadcasted after initial set. The time between casting of concrete and broadcasting depends upon the temperatures.

Application Instructions

HARD TOP-70 is a dry shake finish and should be applied in two operations. Floors should be marked in known areas and proper quantities of HARD TOP-70 should be selected as per consumption requirements. The concrete or the compensating under screed base should be free from residual bleed water and sufficiently hardened to allow light foot traffic. Please observe the precautions as mentioned later. Half or one-third of the total quantity of HARD TOP-70 should be evenly dry broadcasted by hand or scoops. Once the material becomes evenly dark by absorption of surface water, it can be floated by wooden or steel trowels but the surface should not be over-worked. Immediately thereafter, the balance quantity of HARD TOP-70 should be evenly broadcasted in the similar fashion but at right angles to the first application and should be similarly floated. Final finishing can be carried out by normal methods or power trowels. Proper curing should be ensured. Foot traffic can be allowed after 18 hours and heavy stresses should be allowed after minimum week’s time.

Precautions

Since the performance of HARD TOP-70 depends upon the application following precautions should be taken:

HARD TOP-70 application should begin at the time when the base concrete has reached initial set and has stiffened enough to enable light foot traffic and leaves an impression of about 2-3 mm. The bleed and surface water should have been evaporated. Too early application will sink the hard aggregates and give rise to dusting and too late application will not hydrate the binder of HARD TOP-70 thereby lowering the strengths. Curing is absolutely essential and can either be carried out by conventional methods or by using membrane forming curing compounds.

Joint should be properly designed and provided. Treat areas adjacent to walls, columns, and bay edges first. Broadcasting of HARD TOP-70 should be in perpendicular directions in two operations.

Consumption

For the sake of consumption, the surfaces are classified into three categories depending upon the mechanical stresses they are subjected to. The consumption will depend upon the degree of stress.

Since the grading of aggregates in HARD TOP-70 plays important role in the quality of the material as well as the surface, always use in multiples of full packs. If in case consumption of half or a part bag is called for, empty full bag, mix thoroughly and use half contents.

Packing & Storage

HARD TOP-70 is supplied in 30 kg. sacks in natural Grey colour.

HARD TOP-70 is cement based product and therefore should be stored similar to cement. It should be stored in original, unopened packing in dry place away from moisture. Do not stack more than 5 bags on each other as the product is likely to harden under continuous load. Shelf life one year from the date of manufacture.

The further compensating layer should be about 25-50 mm thick consisting of cement to aggregates 1:3 (50% 4-8 mm and 50% 0-4 mm). Cement content should be at least 400 kg per cu.m. and water – cement ratio between 0.45 – 0.50.

NOTE: This information contained herein is believed to be accurate from the time of publication. But no warranty is made with respect to any results obtained or the infringement of any proprietary rights. No liability is accepted at user’s sole discretion.