[TimT]

That the concrete heaved is not the fault of the concrete, it caused by poor preparation of sub-base.. there maybe inadequate drainage of the sub-base which can cause heaving when cold,, and settling when warm,

The first two pictures you posted are classic photos of poor workmanship finishing the concrete.. masons often like to "bless" the concrete by taking a brush and broadcasting extra water onto the surface, to make it easier for them to close and finish the surface.. The term "bless" comes from the similarity to what a Priest does with the holy water during blessings...

The extra water added changes the water/cement ratio at the surface.... sure is looks nice... nice brushed texture.... in reality is is a weak layer that offers poor durability, as shown so perfectly in these photos...

At a minimum there are two causations for your problems, well actually one... poor preparation of the sub-base, poor work manship with concrete of questionable quality ( slump, air content)

Me just a nobody, ACI certified since 1982.. P.E. and all that crap...