how to make a concrete beam?

You can google this information.

Show the work your company has done, particularly on steep grades, basements, stairs, and foundations. Anyone can do level flatwork. It takes professionals to do the unusual.

My guess is that they are worth a great deal. Don't sell them until you do some real research through some dealers. (reputable of course)

Concrete spalling is a common occurance, especially on exterior surfaces that are exposed to freeze and thaw cycles. It's like scaling, but involves bigger chunks breaking loose for no apparant reason. There are many causes such as improper finishing methods and curing methods. Simple repairs can ...

Try mixing 20% bleach with water, scrub with heavy broom or brush. may take several times. Be careful not to touch the colored concrete. If you become happy with the cleaning, clean the whole walk and seal it with a good penetrating sealer.

For a low tech variation of the answer above, just use a small finish nail to probe the ceiling. You should be able to get close by tapping the wall and notice where it sounds more solid.