Hello Everyone,
                            I am new to this forum and hopefully I can get some help with a issue that I having with my Concrete Driveway.

Last year we buillt our house and the concrete guy that came out to pour driveway also tied the driveway with rebar into the footings of the garage (he claimed this is how he always did it). Well later that winter my concrete cracked along the top part of the driveway (where it was tied into the footings).

When I called him and he basically blaimed the guy who did the job for him and long story short he replaced the top side of the driveway and  again used rebar to tie the driveway into the footings of the garage (keep in mind my garage floor is attached to my house) so its below the frost line.

Well guess what- I just noticed a crack running all along my driveway .. I told him and he said he will have to look into it in the next couple of weeks.

Heres my thought and where I need your help..

I would venture to guess you shouldnt tie a driveway (or anything that is above the frostline) to something that is below the frost line, Am I correct for thinking this or else it will crack. Expecially when you drive a car across it in and out of a garage.

Am I correct with this thought???

I need some assistance with ythis please.

Lukeshywalker,

 

I have seen this before. It's diffacult to have two large items tied together under different conditions. In your case, having deep gravel fill well drained would also haved helped. Score cuts help here too.

We put a room addition on our home. The lot was sloped. The addition had a bacement/garage. Where the two joined, the footings were 8' deeper on the bacement. The wall were pined with Rebar. Up to this point, we never had any cracks in our block walls. But during a very dry Summer, the main house "tried" to settle due to soil shrinkage. A huge step crack appeared near the connection. Latter, when the rain returned the crack completely closed up.

Patrick t

Typically an expansion joint, 1/2", is used to keep the two slabs separate. In residential few people use the expansion joints.

The edges of the slabs can be thickened to whatever depth necessary, say 6-8", however, the expansion joint allows the two slabs to move separately, meaning the driveway can rise each winter, and settle back in spring. Because of anticipated movement, the rebar should not be used in climates with frost heave issues.

The frost wins every time!!

You are lucky it didn't lift your house. I have been a construction consultant for 18 years and looked at numerous problems similar to what you have.

Anywhere the earth freezes, never ever connect part of a structure on a frost footing to a structure that is not on a frost-footing. Yours is the classic example. Sidewalks and driveways should be separated from the house with expansion material.

Floating slabs can rest on a ledge, but it has to be able to move freely up and must still have expansion material. Furthermore the floating slab should not extend under things such as siding, trim and thresholds. Post footings should not taper down as the friction of the dirt will cause footing to heave or lift. I have seen numerous post footings not connected to a floating slab, but not separated by expansion material heave, due to friction; resulting in lifting entire 3/4 season porches and twisting everything.