SHRINKAGE CALCULATION OF CONCRETE 1

Tstruct · Sep 4, 2024

Hello,
I have to provide a plain concrete mass to make a trench for cables. Length of this trench is 15'. Sectional dimensions can be seen below.

What I am concerned about is whether there be enough shrinkage in this 15' long mass of concrete to develop cracks?
How can I check it? What would be the permissible limits and precautions?

DTS419 · Sep 4, 2024

I wouldn't bother trying to calculate that. Re-entrant corners are crack magnets. You can chamfer the corners to eliminate the 90-degree angles and/or add a diagonal rebar behind each corner like is commonly found around openings in walls.

bones206 · Sep 4, 2024

Is there anything restraining it from shrinking? If it’s a 15 ft long chunk of concrete free to shrink without restraint, cracking should be minimal.

Tomfh · Sep 4, 2024

Whether it cracks depends on the degree of restraint.

You might get away with it.

I don’t think it warrants being fully reinforced but a layer of mesh 6” off the bottom wouldn’t be a bad idea.

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

SHRINKAGE CALCULATION OF CONCRETE 1

Tstruct

Structural

Recommended for you

DTS419

Structural

bones206

Structural

Tomfh

Structural

Similar threads

Part and Inventory Search

Sponsor