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Q: What is the affect of age of concrete upon the water cement ratio and strength curve?
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Why in case of high strength concrete you are getting step snoop of curve after cracking of concrete?

gravitation is inversly proportional to weaight


Stress strain curve for brittle material?

Brittle materials such as ceramics do not have a yield point. For these materials the rupture strength and the ultimate strength are the same, therefore the stress-strain curve would consist of only the elastic region, followed by a failure of the material.


What is the strength of c plus plus?

Ease of use (after the learning curve, of course), performance and efficient use of memory.


What is difference between characterstic strength and compressive strength?

A characteristic strength is the strength of the material used for design purpose, and is statistically defined by the lower 5% fractile of a bell curve. Compressive strength is a generic term that could refer to anything


Why is high tensile steel wire used in prestressed concrete?

To mobilise the compressive strength of the full thickness of the slab. For an explanation see below. Concrete tends to be stronger in compression than tension. If you can imagine a large flat slab of concrete that is much wider than it is thick (for example a slab to be used in the construction of the floor of an upper level of a house), it will be supported at the corners or edges. This allows the centre of the slab to deform vertically downwards (by a very small amount). This deformation due to it's own self weight generates stresses in the slab. You now need to imagine that there was a straight line drawn along the centre of the edge of the slab from one end to the other. When the slab deforms this line will become a curve or arch. This is in fact what the slab is doing - performing as an arch. This means that the lower portion of the slab (below the line will have stretched and be under tension and the upper portion of the slab will have been compressed. Now in this case the failure strength of the arch is being controlled by the tensile strength of the slab which is much lower than it's compressive strength. As such when the concrete is being formed, high tensile strength steel wires are connected to anchor points in the factory and they are stretched or placed under a tensile stress. The concrete is than poured into a mould around the steel wire and allowed to set (or cure). The concrete than adheres to the steel cable. Once the concrete has fully hardened the stell wires are cut from the anchor points and the steel wires attempt to return to their original size, This stress is transferred to the concrete as compression by friction due to the bond between the c able and concrete. Now when the concrete slab is used as a floor it begins to deform under it's own weight, however the pre-stressed steel wires already under tension act to pull the entire slab including the base back into a compressive stress state meaning that the whole of the slabs compressive strength is mobilised rather than just the upper half and this effectively acts to make the slab stronger. There are a number of differing methods of making steel reinforce pre-stressed concrete and for further information, please see the related link.

Related questions

Why in case of high strength concrete you are getting step snoop of curve after cracking of concrete?

gravitation is inversly proportional to weaight


How can training improve the strength curve?

There are several factors when it comes to improving ones strength curve, Improve your acceleration ability,starting strength,speed strength, and improving Amortization.Improve these factors and you will transform your strength curve.


Does strength curve relate to any exercise?

Yes, any movement at all relates to the strength curve.


Does the strength curve Analyze the components of strength production?

Yes. the strength curve breaks down force by showing starting strength, acceleration strength, and explosive strength as well as many other components


What is strength curve?

Relates to any exercise, Analyzes the components of strength production, Has seven factors


Assumptions of ultimate load method?

1. Plane sections normal to axis remain plane after bending. This implies that strain is proportional to the distance from neutral axis. 2. Maximum strain in concrete of compression zone at failure is 0.0035 in bending 3. Tensile strength of concrete is ignored. 4. The stress-strain curve for the concrete in compression may be assumed to be rectangle, trapezium, parabola or any other shape which results in prediction of strength in substantial agreement with test results.


How would a rise in business affect the aggregate demand curve?

The aggregate demand curve shifts to the right


What are the factors affect the shape of the magnetization curve?

there is no factors


How would a rise in the business investment affect the aggregate demand curve?

The aggregate demand curve shifts to the right


What make a curve ball curve when you throw it?

Three things affect the trajectory of a curve ball: Coriolis effect, gravity and precession AKA spin drift.


How does public capital affect a nation's curve?

By increasing output


How does surface area affect the cooling curve?

put it in the fridge