3-Structural steel sections-an easy approach.

Structural steel sections.

Structural steel sections-video.

The video discusses The various types of structural steel sections and the symbols used for each type. What are the differences between the structural steel sections? The video has a subtitle and a closed caption in English.

Structural steel sections.

As an introduction to the structural steel sections, we will look at the different steel shapes. As you can see from the shown slide, the shapes include W-shapes, M-shapes, S shapes Hp- shapes, C shapes, L-shapes, Wt- shapes, St shapes, and Hollow sections with symbols Hss- shapes.

For angles, we have double angles. And also pipe shapes.

The symbol W stands for wide Flange, which is I beam shapes. The symbol M stands for Miscellaneous beam.

The miscellaneous beam is also an I- beam with a narrow Web. The S-shapes have a considerable slope in Flange pointing inwards.

The Hp shapes are used in Bearing piles. The symbol C stands for  Standard C channel. We cut from an original w section to form the Wt section to form a W.T. section. Wt stands for T section originally from the W section.

The symbol St designates a  Tee section cut from an S section. Wt from the table is T Cut from W. The MT stands for Tees cut from the Miscellaneous section M And St sections are tees from S shapes. HSS stands for the rectangular hollow structural section and also for round shapes and pipes.

The ASTM designation fr the different structural steel sections.

For the next slide,  the following table contains the shape and ASTM designation. The wide Flange beams its ASTM-A-992, Fy is from 50-55 ksi and the Rupture stress is 65 ksi. For Miscellaneous beams and their ASTM designation, ASTM-A-36, Fy is 36 ksi, and the Rupture stress is from 58-80 ksi.

W-section is one type of Structural steel section.

In the next slide, we have considered one section from the w section. We check section W 44×335. The number 335 stands for The weight per unit length.

The Area is given in inch^2. The Area for  W44x335 it is =98.50 inch^2. The total depth of the whole section, which includes the Flange and web Is called d, which is the distance from the top to bottom.

The thickness of the web is called tw, and it has a value of 1.03.” It is obtained from the table. As a part of the sketch, tw/2 is also given in the table.

The next column gives the thickness to the nearest 7/16″. The width of the Flange is bf and is given as 15.9″, its thickness is tf=1.77″. The k value is the vertical distance from either top or bottom till the end of the round portion.

K1 is the horizontal distance from the y-axis to the end of the round. T is the vertical distance that is measured from the upper end of the round portion to the lower end of the round along the web.

There is also a column for the architectural dimension as a workable gauge. I quote, that the most commonly used structural shape is the wide-flange Or W-shape.

This is doubly symmetrical about both the x and y axes. Flange faces are essentially parallel with the inner Flange distance for most of the groups.

How to derive the corresponding SI units for a section?

The next slide, is Table17-1, Si equivalent of standard U.s shape Profiles.

One pound-force is the force that acts on 1 lb mass with an acceleration of 32.20 ft/sec2. The corresponding acceleration in SI units is 9.8066 m/sec2. One Pound mass=0.4536 KG mass.

So we could write that One pound-force is the force that acts on 1Lb mass with an acceleration of 9.8066 m/sec2. Substituting for 1one pound mass as 0.4536 kg.

So we could write that One pound-force is the force that acts on 0.4536 kg mass with an acceleration of 9.8066 m/sec2. We can get that one pound-force =(0.4536*9.8066)=0.4536 of Kg force.

For a W44x335 W structural steel section. the overall height is 44 inches since one inch =25.4mm. The first figure will be 44*25.40=1117 mm taken as 1100 inches.

One ft =30.48 cm=304.8*(1/100)m=0.3048 m. For 44 lb/ft=335(0.4536/0.3048)=498.543 kg/m=499 kg/m. This means that W44x335. The second term is 355 is the pound Weight per linear foot. The exact section but in Si- units will be W1100x499.

But with 499 km/m. The overall depth is approximately 1100mm.

The difference between W and S shapes.

The next slide will show the difference between W and S shapes, two types of structural steel sections. The flange width with the section is less. The inner face of the Flange has a slope of approximately 16.7 degrees. The theoretical depth is the same as the nominal depth.

For instance, an S510x111.6 is a shape of nominal depth 510mm With a weight of 111.60 kg/m.

To get The dimension in lb-Ft for the depth=510/25.40=20.07 ft taken as 20′. While for the weight =111.60/(0.4536/0.3048)=75.00 lb/ft.

M-section is one type of Structural steel section.

In the next slide, M shapes are doubly symmetrical shapes, and M shapes are Not classified as W, or S.M stands for miscellaneous. There are 20 lightweight shapes classified as M. An M360x25.60 is the largest M shape and is a section of nominal 360mm depth with a mass of 25.6 kg/m. The overall depth is 14 inches, and the weight is 17.2 pounds per linear foot.

C shapes and Hp structural steel sections review.

In the next slide, we will check the C-shapes. We have a flange and a web. The table of the C-channel includes the flange width as bf, and the average thickness is given as tf.

In the table, there is a web height and thickness. The web height is measured from the Overall depth of the C-channel, which is d minus 2k.

The first column in the table of C- Channel includes the Area. For a C channel, C15x50. The overall height d is 15.0 inches, And the weight is 50 pounds per foot. K value is the distance from the end of the slope to the upper Flange.

The T is the distance between the upper end of the slope to the lower end of the slope. Table 1-4 is from the AISC tables.
H-P shapes are used as bearing piles. H.P. section of 18×204. The overall depth of that section is approximately equal to 18 inches; the actual depth is 18.30 inches. The is a slope and a round portion. Table 1-4 gives complete information on Flange and web data.

MC-angles, structural steel sections review.

In the next slide, we have MC-Shapes—the Miscellaneous C-shapes. This is the second part of the table that includes the nominal weight. Every table has two parts; the first part includes data for the Area, Flange, and web data. The second part consists of the elastic and plastic section modulus and the inertias and radii of gyration.

We will take about the elastic section modulus and plastic section modulus in the beam section by God’s will.

r stands for the radius of gyration, which is equal to sqrt of I/A. S stands for the elastic section modulus.

Z is the plastic section modulus. Torsional properties are given, Ix is bigger than the inertia about the y-axis. There  is Sx and Sy in inch3, rx=sqrtof(ix/A), while ry=sqrt(Iy/A), x bar. Zx the section modulus, J is the polar moment of inertia.

cw &h are for the torsional data estimation. The next table is for angles. For a section, L8x8  represents an equal angle of 8 inches. K value is given. The values of weight and Area are given.

WT-shapes and Si equivalence.

In the next slide, we have data on the W.T. shape; these T-sections are cut from a W-section. The table includes the different sizes of the WT shapes.
We have the web, in that case, is called the stem, we have bf for the flange width, tf is the flange thickness. The stem is the vertical portion of the WT shape.

The area and depth are included in table 1-8. These are corresponding sizes in S.I. units. WT205x29.8 is a structural tee with a nominal depth of 205 mm and a mass is 29.8 kg/m. Wt shape is due to the cutting of a W- section of w410x59.6. The W-section is a double depth of the needed W.T. section.

The x-axis data includes the values of inertia, elastic section modulus& radius of gyration, y-bar, and plastic section modulus. w section will have a double weight as compared with the required W.T. section. W16x40 will produce Two Wt sections of 8×20.

In the next slide, A summary given of the various items. A W27x114 is a W section that is approximately 27 inches deep and weighs 114 pounds per foot. An S12x35 is an S section 12 inches deep, weighing 35 pounds per foot. An HP12x74 is a bearing pile section approximately 12 inches deep and weighing 74 pounds per foot. bearing piles are made from regular W rolls but with thicker webs to provide better resistance To the impact of pile driving.

An M8x6.5 is a miscellaneous section 8 inches in deep, weighing 6.5 pounds per foot. It is one of the groups of doubly symmetrical. H-shaped that cannot by dimension be classified as a W, S, or H.P.

Miscellaneous has a different shape than other sections.

Cold-formed shapes.

The previous section was about the hot-rolled section. The next slide shows the cold-formed shapes. The cold Formed shapes include Channel, stiffened channel, Zee, stiffened zee, hat, and sigma. An angle section also can be formed for a cold-formed section.

This is the Pdf data used for this post.
The next post will include the different types of structural loads and an introduction to LRFD and ASD designs.

if you want to see the major changes between Cm#14 and CM#15 regarding the different grades of steel and their uses for steel elements and bars please refer to post 1A.

A very good reference, is A Beginner’s Guide to Structural Engineering.