What is creep & shrinkage of concrete?
Creep and shrinkage of concrete are two physical properties of concrete. Unlike the creep of metals, it occurs at all stress levels and, within the service stress range, is linearly dependent on the stress if the pore water content is constant.
How creep and shrinkage affect strength of concrete?
Concrete mix proportion: creep is inversely proportional to the strength of concrete. Factors affecting creep 2.. Aggregate properties: The higher the modulus of elasticity the less is the creep. Light weight aggregate shows substantially higher creep than normal weight aggregate.
What is creep of concrete?
Concrete creep is defined as: deformation of structure under sustained load. Basically as long term pressure or stress on concrete can make it change shape. This deformation usually occurs in the direction the force is being applied. Like a concrete column getting more compressed, or a beam bending.
What are the limitations of high performance concrete?
Disadvantages of high performance concrete:
- These HPC have extended quality control.
- This concrete has a high cost.
- They are special constituents.
- They are manufacture and placed carefully.
What is difference between creep and shrinkage?
In shrinkage, the loss is due to difference in the relative humidity of concrete and the environment, in creep it is due to sustained applied stress. Second, the strain-time curves of both the phenomenon are very similar. The factors that effect creep also effects shrinkage.
What is effect of creep?
The ability of the material to flow under the effect of temperature is known as creep. Hence, deflection is directly proportional to the creep of the material. • The creep can lead to the condition of buckling in case of columns, as creep increases the deflection of the column over a period of time.
What is the effect of creep in concrete?
Effects of Creep on Concrete and Reinforced Concrete In reinforced concrete beams, creep increases the deflection with time and may be a critical consideration in design. In eccentrically loaded columns, creep increases the deflection and can load to buckling.
What is the shrinkage of concrete?
Drying shrinkage is the contraction in the concrete caused by moisture loss from drying concrete. Shrinkage-compensating concrete is used to minimize cracking and structural movement caused by drying shrinkage in concrete.
What is shrinkage and types of shrinkage?
Types of Shrinkage in Concrete Plastic Shrinkage. Drying Shrinkage. Autogenous Shrinkage. Carbonation Shrinkage.
What are the effects of shrinkage in concrete?
Shrinkage of the concrete causes the concrete to grip reinforcing bars more tightly. This increases friction between concrete and steel and so improves bond strength, especially for plain bars.
What will happen to a concrete if creep occurs?
Concrete creep is defined as the deformation of structure under sustained load
What is the difference between creep and shrinkage?
The Difference between creep and shrinkage in concrete – Creep Depends on stress & loading condition, Shrinkage does not depends on loading condition or stress. Shrinkage – Volume decreases with time causes strain. Creep – Under constant stress it goes under gradual deformation. Both are two different concept.
What are the disadvantages of creep in concrete?
The following are the disadvantages of concrete. -when creep starts, gradual transfer of stress from conc to steel occurs that lowers the neutral axis and hence more depth of conc comes into compression zone to resist compression. ~ Water having a pH value less than 6 is not suitable for use in plain cement concrete.
What is the effect of creep on concrete structures?
Effects Of Creep The deflection of the structure increases at the time of usage of structure over a period of time. The creep can lead to the condition of buckling in case of columns, as creep increases the deflection of the column over a period of time. The creep plays an important role while considering the internal stresses developed in the structure.