Stone

Stone??

Part of Building Material???

-a building material since thousands of years ago.

 -     recognized as a material of great durability and superior artistic quality, the foremost choice for buildings associated with status, power and religion.

-       Stores can be either artificial or natural.

ARTIFICIAL STONES

- name for various kinds of synthetic stone products used from the 18th century onward.

                       -  Sometimes it is called Engineered Stone.

                       -  a production line is set out to produce high-quality artificial stone which

                          can be used in used in building construction, civil engineering work, and

                          industrial uses such as grindstones.

The flow chart of artificial stone production line is a dragon automatic production line. The craft principle is:

Artificial stone finished product moulds :

NATURAL STONES

- obtained by taking rocks from earth and cutting them to the sizes and  

                          shapes for construction.

                        - 3 types of rocks are quarried to produce building stone which is igneous 

                          rock, sedimentary rock and metamorphic rock.

Igneous rock

-  formed from molten or partly molten material 

i.e. magma, through solidification of magna.

                           As the magma or molten rock cooled, it crystallized giving the granular   

                           appearance typical for this type of stone. 

Granite tiles and basalt tiles 

Granite tiles and basalt tiles comes under this category. The Basalt tiles in particular are such a strong and different look that we very much encourage our design conscious customers to consider them.
Metamorphic     -     the most recent of the different types of natural stone.
                          -     This transformation was usually a result of the intense heat and pressure
                                    arising from movement in the earths crust.

Metamorphic rock tile

Sedimentary

 -     Formed in more recent times than igneous, sedimentary rock is the

                              result of various deposits settling layer upon layer in ancient lacks,

                              rivers and seas.

                       -    Softer than igneous rock, though still more than tough enough to last

                             for centuries as natural stone flooring. 

Sandstone

Sandstone—Another stone susceptible to staining, sandstone's softer texture and beautiful appearance still make it a reasonable and popular choice if you're willing to take care of it.

How do Blocks made?

How do blocks made ??

Blocks

Blocks

Blocks are larger than bricks as it requires both hands to lift it for laying. Moreover, they can be laid more quickly which means it is larger than bricks. Therefore, it is less versatility in laying especially when building up ends, corners, and curves. Blocks are also intended to be plastered. Blocks are categorized into two types, which is clay blocks and concrete blocks. However, concrete blocks are widely used in construction industry.

Clay blocks are commonly extruded hollow units (Refer to figure 1). The monolithic clay block wall provides a unique combination of thermal insulation and heat storage. The natural air conditioner ensures a relatively constant indoor temperature as well as protection from the heat. (Refer to figure 2). The standard sizes for wall blocks are also shown in figure 1. Material used in manufacturing the blocks is usually the same as clay bricks. Clay blocks are dense, hard and brittle after firing. This caused difficulties in cutting and fixing them.

Figure 1

Figure 2

The following data is the minimum average compressive strength of clay blocks:

-1.4 N/mm² for non-load bearing wall or partitions
-2.8 N/mm² for facing and common blocks
-2.8 N/mm² for loadbearing internal walls

On the other hand, concrete blocks are primarily used as a building material in the construction of walls. A concrete block is one of several precast concrete products used in construction. Concrete blocks are found in either dense or lightweight. One of the advantages of using lightweight blocks is its easier to handle and quicker to lay. Next, the air in the lightweight blocks provides better sound and thermal insulation. Furthermore, these lightweight blocks result in lighter foundations and structural members. Moreover, they can be cut and chased with hand tools and hold nails as well as screws without plugs. Thus, it is mostly used in internal wall partitions.

Concrete blocks are divided into three types which are solid blocks, hollow blocks and cellular blocks. There are no formed holes or slots in solid blocks. Conversely, hollow blocks have cavities that can pass through whereas cellular blocks have cavities that cannot pass through. The sizes of the typical work are shown in table 1.

Table 1 BS 6073 Work Sizes for Manufacture of Concrete Block 

The minimum crushing strength of concrete blocks is shown in Table 2.

	Concrete density1 , kg/mm3	Strength, N/mm2
Dense aggregate	1500 – 2000	2.8 – 3.5
Lightweight aggregate	700 – 1500	2.8 – 10.5
Autoclaved aerated	400 – 900	2.8 – 7.0

¹ weight of block divided by overall volume

Table 2

To prevent shrinkage cracks, the use of blocks with low drying (reversible) shrinkage is important. It is also vital to take necessary precautions described for calcium silicate brickwork. Thermal conductivity of blocks depends on the density. Lightweight concrete blocks have better thermal insulation. Besides, it has good fire resistance property.

The durability of those factory-made blocks is commonly good. The blocks made with dense aggregate and having a compressive strength at a minimum of 7 N/mm² can be used for external walls and below the ground level as damp-proof courses. The bonding pattern and quality of workmanship is essential for its good appearance. The appearance of concrete block work is also depends on the quality of blocks and the mortar used.  

 

 

    

GO Green (Bricks)

Sustainable Technology - Green Brick 

 

CalStar Products Inc. plans to open a factory next month to make bricks from fly ash, a byproduct of coal burning. It claims to use roughly 85% less energy than traditional clay brick manufacturing, with an equivalent reduction in carbon-dioxide emissions.

The process for making clay bricks—mining clay, forming it into bricks and firing in kilns using coal or natural gas—has remained largely unchanged for decades, though manufacturers have made improvements to reduce environmental impacts.

CalStar forms its bricks from fly ash—a gray, chalky byproduct of burning coal— and a proprietary stew of chemicals. During eight hours of steam baths, the calcium in the fly ash hardens, making bricks that look, feel and act like their clay counterparts, Mr. Kumar says.

 CalStar says the bricks are designed to meet standards set by ASTM International, a standards-setting organization, for things like strength, durability and water absorption—and will be installed in buildings for the first time early next year. CalStar says the bricks will be priced competitively with commercial clay bricks. In Chicago, for instance, its bricks will sell for 53 cents apiece on average, compared with 55 cents on average per commercial clay brick, Calstar says.