Time to remove formwork to cater for early thermal movement, Civil Engineering

Assignment Help:

Q. Time to remove formwork to cater for early thermal movement?

Let's take a circular column as an illustration to explain effect of internal restraint to thick sections. 

When temperature is increasing, temperature in the core is higher than outer zone. The inner core would have a higher expansion and exert pressure to the outside. Induced compressive stress will yield the formation of radial cracks near the surface of concrete.

When temperature drops, concrete at outside drops to surrounding temperature whereas the concrete at central region continues to cool down. Contraction associated with inner concrete persuades tensile strains and forms cracks tangential to circular radius. 

It is advantageous for thick sections (say >500mm) to have late removal of formwork to decrease early thermal cracking. This is to enable more time for the centre of concrete section to cool down progressively to decrease the risk of thermal cracking. It is effective in controlling thetemperature differential across the cross section of concrete structures and decreasing the potential of internal cracking because of early thermal movement.


Related Discussions:- Time to remove formwork to cater for early thermal movement

Surveying, What is fore bearing and back bearing?how it measure?

What is fore bearing and back bearing?how it measure?

Maximum shear stress , the propane gas tank has an inner diameter of 1500mm...

the propane gas tank has an inner diameter of 1500mm and wall thickness of 15mm. If the wall is pressurized to 2MPa, determine the absolute maximum shear stress in the wall of tank

Compute the stresses at top and bottom fibres, Compute the stresses at top ...

Compute the stresses at top and bottom fibres in a simply supported pre-stressed concrete beam with a rectangular cross section, 200 mm wide and 400 mm deep at sections A-A, B-B an

Application of bitumen to driven piles, Q. Application of bitumen to driven...

Q. Application of bitumen to driven piles? In a certain area of H-piles subjected to ground water table fluctuation, painting is occasionally applied on the surface of H-piles

Rb slab, #questionshow me picture..

#questionshow me picture..

Harbours, natural phenomenon affecting the designs of harbours

natural phenomenon affecting the designs of harbours

Ghgh, Ask quhestion #Minimum 100 words accepted#

Ask quhestion #Minimum 100 words accepted#

Concrete technology, why strength of transition zone is less than bulk past...

why strength of transition zone is less than bulk paste

BESHOOOOO, what are the dimensions of a sheet of paper required for plottin...

what are the dimensions of a sheet of paper required for plotting a traverse ABCDE with 1 : 250 scale if a margin of 4 cm to the right and left sides and a6 cm margin to the other

Correction in bearing, write a c program To compute interior angles and cor...

write a c program To compute interior angles and correct them for observational errors and adjusting the bearing of remaining sides when the bearings taken on a closed compass trav

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd