AGEING DAMAGE OF IMMERSED SYNTACTIC FOAMSUNDER COUPLED EFFECTS OF PRESSURE AND AQUEOUSCORROSION

摘要

This paper reports the results of a research activity concerning the hygro mechanicalbehavior and the estimation of the lifetime of syntactic foams used as isolator of immersed oil risers. Amulti-scale simplified approach was adopted based on the self-consistent method. An iterative processis also proposed to extend the field of validity of this method to high volume fraction of micro spheresand to correct the micro-stresses in order to better exploit them in damage criteria. The phenomenon ofdamage modeled in this work is a physico-chemical ageing of hollow glass spheres. A simplified lawdescribing the speed of formation of a corroded layer is proposed. This law coupled to a chosenfailure criteria delivers a first estimation of foam lifetime in operational conditions.