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a coupon is placed in tensile test machine and pulled on along its axis with a known load; when it breaks that is its tensile load strength; divide by coupon cross sectional area to get ultimate stress. Usually the coupon is shaped as a dog bone to provide grip at the ends and failure in the middle
Take a piece of any material, say a steel rod, or a piece of timber dowel and you grip it at both ends and try to pull it until it breaks. When you do this, you are putting a tensile load on the material. It is said to be 'in tension'. If the material had a cross sectional AREA of say, 1 Square Inch, and the Tensile Load on it was say, 50,000 Pound,then the Tensile load would be 50,000 PSI (pound per square inch). If the material broke apart under that exact load, then we say it has a TENSILE STRENGTH of 50,000 lb/ square inch. Engineers measure tensile strength in either Pound/Squ.inch. OR Pascal. A Pascal (metric system) is Newton per Square Metre. Steel cables used on bridges have a Tensile Load on them at all times. Engineers calculate the cross sectional area of steel cable needed to be safe , and never break apart. Engineers need to know the Tensile Strength of Steel to be able to choose what size cable to use,so that it is quite SAFE and will not break when in Tension. They use safety factors such as 5 (typical) This means they calculate the cross sectional area of a cable which is going to be 5 times as strong as the Tensile Strength of the steel they are using. They then know that it will never break. The Tesile strength at which a material breaks is called its Ultimate Tensile Strength. Engineers never allow the tension in steel to exceed about 1/5th ofthe Ultimate tensile strength of the steel. Modern Steel bars used in steel structures, has an ultimate tensile strength of approx. 80,000 lb/Squ.inch
It all depends on the dimensions of the steel beam
Tensile strength is one of the basic and important properties of the concrete. The concrete is not usually expected to resist the direct tension because of its low tensile strength and brittle nature. However, the determination of tensile strength of concrete is necessary to determine the load at which the concrete members may crack. The cracking is a form of tension failure.
Think of a tensile load as a "pulling" force. A tensile load is the only type of load that can be taken by a rope, for instance.
It is a failure caused by a load in tension; that is, a force that stretches the material. For example, if you pull a beam along its axis and stetch it until it breaks, that is a tensile failure.
A sample is tested using a tensile test machine by loading it in a direction along its axis. The load is measured with a load cell, and when the sample breaks its tensile strength is determined by dividing the failure load by its area.
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a coupon is placed in tensile test machine and pulled on along its axis with a known load; when it breaks that is its tensile load strength; divide by coupon cross sectional area to get ultimate stress. Usually the coupon is shaped as a dog bone to provide grip at the ends and failure in the middle
tensile stress=tensile load/cross sectional areaex. tensile stress= p/a= 50kilo newton x 1000n/kg divide by pi/4(20)^2=159.15N/mm^2
tensile stress is due to just the tension in the load whereas breaking stress can be due to breaking,shearing or compression!
If the test is set to load-control , it means that the stress will not drop once the fracture become unstable. In displacement control the stress may drop at unstable fracture.
Take a piece of any material, say a steel rod, or a piece of timber dowel and you grip it at both ends and try to pull it until it breaks. When you do this, you are putting a tensile load on the material. It is said to be 'in tension'. If the material had a cross sectional AREA of say, 1 Square Inch, and the Tensile Load on it was say, 50,000 Pound,then the Tensile load would be 50,000 PSI (pound per square inch). If the material broke apart under that exact load, then we say it has a TENSILE STRENGTH of 50,000 lb/ square inch. Engineers measure tensile strength in either Pound/Squ.inch. OR Pascal. A Pascal (metric system) is Newton per Square Metre. Steel cables used on bridges have a Tensile Load on them at all times. Engineers calculate the cross sectional area of steel cable needed to be safe , and never break apart. Engineers need to know the Tensile Strength of Steel to be able to choose what size cable to use,so that it is quite SAFE and will not break when in Tension. They use safety factors such as 5 (typical) This means they calculate the cross sectional area of a cable which is going to be 5 times as strong as the Tensile Strength of the steel they are using. They then know that it will never break. The Tesile strength at which a material breaks is called its Ultimate Tensile Strength. Engineers never allow the tension in steel to exceed about 1/5th ofthe Ultimate tensile strength of the steel. Modern Steel bars used in steel structures, has an ultimate tensile strength of approx. 80,000 lb/Squ.inch
Tensile strength depends on the material. Is it steel? up 100,000 psi or higher. Is it aluminum? That is 50,000 psi or lower. For your 6 x 8 x 1 tensile strength (stress) is the same no matter the hole, but the tensile load to failure is lower by the ratio of width remaining after hole removal; for example 4/6 ,if you are loading in direct axial direction.
It all depends on the dimensions of the steel beam