Hollow Cement Concrete Bricks

1) Product & Applications

Concrete block technology is based on the principle of densification of a lean concrete mix to make regular shaped uniform high performance masonry unit. Concrete block technology can easily be adopted to suit special needs of users by modifying design features such as mix, proportion, water/cement ratio etc. Hollow and dense cement concrete blocks popularly known as Hollow bricks have been developed as an alternative to commonly utilized mud clay bricks used in construction industry. The product is widely used in construction of houses. These blocks have certain superior qualities as compared to ordinary bricks as they have better tensile strength. The other important feature of these blocks is that the walls constructed with the hollow bricks have thermal insulation qualities; the rooms are thus cooler in summer as the hollowness provides thermal insulation. These blocks also lower the cost of construction as the sand, stone chips etc are cheaper as compared to bricks. Its cheapness as well as its qualities is the main reasons for its popularity. These bricks can be easily manufactured at the site of construction thus saving in transportation cost.

The technology for such Blocks is available with Government research laboratories. The market for such blocks is rapidly growing with increase in housing development activities and urbanization. It is much needed in regions where traditional bricks are not easily available. It is also popular in case of requirement of low cost housing. The main advantage of concrete blocks is that their strength can be engineered to requirement. Thus making them relatively stronger than bricks by 15-20%. These blocks are 4-5 times bigger than burnt bricks; the size of the block or bricks used has a bearing on the strength of masonry. As the bigger size accounts for reduction in number of mortar joints, thereby increasing wall strength. Concrete blocks have an excellent thermal property, comparable to other masonry blocks. The cavities in the blocks provide better thermal protection and also do not need external or internal plastering. The performance of the blocks increases with increase in number of hollow cores, which may or may not be filled with some insulating material. The hollow blocks provide an acceptable degree of sound insulation. Concrete blocks are inert, non toxic and not prone to off gassing of volatile material.

It has been observed that concrete blocks enable savings of approx 8-9% per sq. mt. of masonry as compared with burnt brick. This is primarily because of the savings in mortar and faster construction speed, both due to larger block size and also due to the savings in plaster. Size optimization of concrete blocks also leads to increase in usable internal space, when compared to conventional fired brick construction. Construction technique involved is similar to other masonry units thus easily adaptable. Through decentralized local production it is easily available through a large number of manufacturers and distributors in most parts of the country in both rural and urban areas.

Applicability: Hollow concrete blocks are commonly used in

•   Load bearing structure: - low rise residential and office buildings, bungalows, shelter units for rural housing, institutional buildings, godowns and warehouses etc.
•   In frame structures: - High rise residential apartment, office buildings, market complexes, Hospitals, Hotels etc.

2) Industry Profile and Market Assessment

Footwear is an essential part of everyday life through out the year be it during hot summer months of winter. Both the summer and winter months are extreme in many parts of the country. The feet have to be protected hence it is essential to wear shoes. Canvas shoes are one of the cheapest available for the purpose. Although shoes made from other material such as leather, PVC etc. are also available in the market but, are many times costly. Canvas shoes are also a popular sportswear and are preferred foe children. These shoes are extensively used by labourers, industrial workers, farmers, and roadside vendors. There is a good demand for such shoes as such a number of renowned shoe makers are in the field. The shoes manufactured by these big units have the market in the richer class of the society and cannot be afforded by the general public. A small scale unit with low overheads can easily market its products with such units if it can keep the prices low. The population of the country is nearing 120 crores, assuming that such cheap shoes can be afforded by 25% the requirement is 30 crore pairs over an extended period assuming a life span of 3 years for a pair. The demand for children shoes is higher as they grow fast and shoes have to be replaced periodically. It has a good demand in rural, urban areas and metropolitan cities. Once the product establishes its Brand, export opportunities can also be explored. Middle East countries and other western countries are places where it has demand.

3) Manufacturing Process & Know How

The process of manufacturing is simple and standardized. It is divided into four sections:

•   Mixing of the concrete in proper proportion .
•   Pouring the mixture in moulds on vibrating platform.
•   Drying of the moulded blocks.
•   Curing of the blocks and drying.

Cement, sand and stone chips in proper proportion are mixed in a concrete mixer while water is added for curing the cement. The mixture is poured in the moulds and vibrators are employed for removing the air pockets and for making the mixture dense. The moulds are generally of standard sizes as 12x8x4”, 12x3x8” or 12x8x6”. This is left for drying for 24 hrs and then the blocks are drowned in water tanks for curing and settling the cement. The process of curing continues for two to three weeks to give the blocks necessary strength. The blocks are dried before use.

Know how is available with Central Government research Laboratories. The machinery is all indigenously available.

The production capacity envisaged is 2.30 lakh bricks per annum on single shift basis for 300 days.

4) Plant and Machinery

The main plant and machinery required comprise

•   Concrete mixer – 1 no.
•   Semi automatic concrete block making m/c with vibrator - 1no.
•   Moulds 4” and 6” wide.

The total cost of machinery including miscellaneous assets such as tools and equipment, is estimated to be Rs.2.00 lakhs.

The total requirement of power shall be 5 HP; the unit will need 3000 lits of water daily.

 6) Raw material and Packing Material

The basic raw material for the unit are Cement, Stone chips, Sand and Stone dust The total requirement at rated capacity is estimated to be :

•   Cement 6000 bags
•   Stone chips 32400 cu ft
•   Sand 32400
•   Stone Chips 32400 kgs

The total cost of raw material and consumables is estimated to be Rs.25.26 lakhs per annum at rated capacity.

At 70% capacity in 1 st year the cost works out to Rs 17.68 lakhs.

7) Land and Building

The unit will require a covered area of 600 sq. f t and curing Tanks. Open space of 2700 sq ft will be needed for drying and storage of raw material. The total cost of land and building is estimated to be Rs.3.00 lakhs.

8) Manpower

For smooth functioning of the unit the requirement of man power is expected to be around 7 persons.

The annual salary bill is estimated to be around Rs.2.28 lakhs. :

9)  Sales Revenue: (100% capacity)

Selling price varies depending on the product mix quality. An average price of Rs 14.50 per block has been taken. The annual income at installed capacity of 2.30 lakh blocks is Rs 33.35 lakhs.

10)  Cost of Project:

11)  Profitability:(70%capacity)

12)  Requirement of Working Capital

13)  Break Even point: 44%

14)  Machinery Suppliers :

M/S Engineers Enterprises ,
Maniyakaranpalayam Road ,
Coinbatore

M/s Victor electric and Machinery Manf.
3616, Netaji Subhash Marg,
New Delhi 110 002.

M/S Buildtech Engineering Co.
Shree Ashadweep Complex, 16, civil Liunes,
Roorkee

M/S Karthik Industries,
36, J.C. Road ,
Bangalore .

M/S Susanji Udyog Pvt. Ltd,
C-47, Industrial Estate, Sanathnagar,
Hyderabad .

M/S Ashok Engineering Works,
81, Ajit Industrial Estate Kakhial,
Ahemedabad.

Contact for more information:

Information Manager
TIMEIS Project
E-mail: timeis@ficci.com