Dynastone® Generation 2 
  Dynastone® is a corrosion resistant cementitious material 
  that is able to resist attack from sulfuric acid generated in the sanitary 
  sewer environment. Dynastone® utilizes a chemically activated high volume fly 
  ash mixture that dramatically improves the durability of the concrete 
  pipe. The fly ash is an integral part of the Dynastone® technology. It acts as 
  a replacement of a major component of the Portland cement commonly used in 
  pre-cast concrete pipe.
  
  Dynastone® offers several advantages over current solutions 
  to the corrosion problem. Dynastone® is much more economical than lining and 
  more economical than coatings. The entire structure is made of an acid 
  resistant, strong material and therefore there is no risk that an inferior 
  quality application of a liner negating the acid resistance of the rest of the 
  structure. Dynastone® is available in both dry cast and wet cast formulations 
  that can be manufactured with any existing equipment in any size. Aside from 
  the requirement of an ash silo, there are no special installation requirements 
  and welding of the joints is not necessary.
  Basic Dynastone® Products