Author: haroonkhan

Steel members are fastened together by means of rivets, bolts or by welding. Among the three approaches welding has been used in most of the works as they have large advantages.

These are the new type bars produced from the ribbed TOR steel which is a deformed high strength steel. These bars have ribs or projection on their surface. The ribbed TOR steel bars are available in sizes varying from 6 to 50 mm diameter. These bars are largely used as reinforcement in concrete structures. These…

Plain or ribbed steel sheets are cut and expanded to form expanded metal. These are used in ferro-cement concrete works. Welded fabric with ribbed mesh has a rectangular or square mesh is another form of mesh used in construction (Fig. 24.1(e)).

These sections are named based on their shapes (Fig. 24.1(c) and (d)). I-section is usually referred to as rolled steel joist (RSJ) or beam. RSJs are used for floor beams, lintels, columns, etc. T-sections are used in steel roof trusses, in built-up sections, in steel water tanks and in chimneys and bridges. The economic use…

It has two equal flanges and a web (Fig. 24.1(b)). A channel section is designated by the height of web and the width of flange and they are available in different sizes. These are used in steel framed structures, girders and steel bridges. Figure 24.1 Commercial sections of steel

The angle section may be of equal or unequal legs (Fig. 24.1(a)) and available in different sizes. Angle sections are used in steel roof trusses, steel columns, beams and as stiffeners in girders.

Flats are plates with longer length with shorter width. The width varies from 18 to 500 mm and thickness from 3 to 80 mm. Flats are comparatively costlier and used in grill works and railings.

Rolled plates with thickness of 5–28 mm and with a maximum area of 30 m2 are available. Thin plates with 5 mm thickness are called sheets. These are used in flanges of beams and columns and as column bases.

Bars are of round or square cross-sections. Square sections of size 5–32 mm are commonly used. Round bars of diameter 6–32 mm are available. Both are available in lengths of 10–12 mm. Square bars are used for railings and of grill work and round bars are used in reinforced concrete and brick works.

In order to use in construction works, steel should be available in certain forms which are known as steel sections in commercial forms or market forms. Some of the common sections or forms are given below.