The life of DCS can be adopted for 100 years as the Dincel-Polymer encapsulation to the concrete infill will not dissolve within 100 years time.
The following is an explanation why 100 years of life can be adopted when DCS is used;
The best studied and experienced product is rigid PVC pipe. The life expectancy of buried pipe is expected to have more than 100 plus years under pressure. When pipes are buried under ground, no chemical degradation is expected to take place. For this reason, the durability of PVC material in buried pipes is expected to be very long (may be even more than 1000 years, Ref: Janson, Lars Eric 1996 “Plastic pipes – how long they can last?” KP Council November 1996).
Studies show that plastics undergo a change in morphology with time, independent of exposure conditions, such that the “free volume” in the matrix reduces with an increasing number of cross-links between molecules. This results in changes in mechanical properties consisting: increase in tensile strength, yield stress and moduli. In general, these changes appear to be beneficial. However, the response of the material at high stress levels is altered in that local yielding at stress concentrators is inhibited, and strain capability of the article is decreased (e.g. pressure pipes). A brittle type of fracture is more likely to occur and a general reduction in impact resistance may be observed.
Real experience in Germany has shown that buried PVC pressure pipes dug up after 60 years of active use were proven to be fit for purpose when analysed and likely to have a further life expectancy of 50 years. (Reference 60 Jahre Erfahrungen mit Rohrleitungen aus Weichmachfreiem PVC, 1995, KRV).
Studies in the Netherlands have examined several potential degradation processes for PVC pipes and carried out tests on pipes up to 45 years old. These studies also concluded that the life of PVC drinking water systems could exceed 100 years. (Reference ‘Long Term Performance of Existing PVC Water Distribution Systems’ by A. Boersma and J Breen, 9th International PVC Conference, Brighton, 26-28th April 2005, pp 307-305).
The website http://matse1.matse.illinois.edu/concrete/concrete.doc confirms that concrete life span is 50,000 years under perfect conditions. This statement is particularly relevant to concrete within Dincel-Wall which is protected against reinforcing steel corrosion and against chemical attacks to the concrete itself, including atmospheric, ground water, acidic and salt attacks.
Dincel-Walls do not incorporate horizontal reinforcement across the adjacent module joints. Therefore, corrosion of the vertical bars in the absence of horizontal bars of Dincel-Wall is not a possibility provided adequate measures are taken for corrosion protection of vertical bars at the wall-floor junctions.
Rigid PVC offers good resistance to acids, alkaline, oils, many corrosive inorganic chemicals, oxygen, ozone, water, alcohol, aliphatic hydrocarbons and detergent solutions. However, rigid PVC is attacked by ketones; some grades are swollen or attacked by chlorinated and aromatic hydrocarbons, esters, some aromatic ethers and amines and nitro-compounds. The chemicals that can attack PVC are normally man-made; the ones available in nature below 20°C in temperature are not in concentrations to affect rigid PVC. This qualifies rigid PVC under normal environmental conditions as an environmentally indestructible polymer.
It is known that brittle fracture of the PVC pipes can occur because of stress concentrations such as high water pressure within pipes or local impact. Pipe is an empty shell carrying high pressure water. Therefore, the abovementioned fracture due to the brittleness of the material would not be relevant if the same pipe profile is filled with concrete to absorb stress concentrations such as local impact as in the case of Dincel-Wall.
It is an obvious fact from the testings performed by the industry that the life of PVC pipes is a minimum of 100 years because they are subjected to cyclic water pressure loading as aged material can crack due to brittleness. However, this does not mean that the material itself will degrade or dissolve. The cracked pipe will remain in position without degradation for hundreds of years. The analogy for Dincel-Wall is no different than the above. Dincel-Wall is not subjected to cyclic loadings such as water pipes, hence in time the brittleness, if any, is not an issue since polymer material will not dissolve within 100 years as stated by Jansen, Lars Eric 1996.
Dincel-Wall performance including resistance to chemicals and a unique crack inducing mechanism eliminating the use of horizontal reinforcement, hence corrosion of steel reinforcement and impact strength to aged polymer provided by concrete infill offers a very long life to Dincel-Wall. Dincel-Wall, consisting of concrete infill and a protective permanent polymer encapsulation, offers perfect protection to reinforced concrete walls. Basement walls or above ground building walls can then be said conservatively to have a life span in excess of 100 years (not 50,000 years, not 1,000 years as mentioned above).