ABSTRACT:Most studies on the PAFSIN pipes were oriented monitoring their behavior in laboratory conditions, focusing on the fluid and less influence on the environment laying on the mechanical properties in the short term then extrapolated mathematical term. Moreover, a large part of these studies refer only to the effect on PAFSIN composite samples without taking into account the specificities induced specific geometry pipeline. In this way, the effect PAFSIN pipes can be overlooked, which in practice can lead to significant errors of design and / or execution. Compared to existing studies, taking into account only the effect of a sealant (generally standardized solutions of acid or base) of the PAFSIN pipes, in the article to present the results of tests conducted on PAFSIN pipes buried in different types of land and attempted to surprise the complexity of the interactions of soil solution to the conduit. * Corresponding

The lifetime of glass reinforced plastic pipes is 50 years. Extensive use of this type of pipe in its various applications, led to investigate their behavior in land that anthropogenic or natural causes, shows the different values of pH to neutral. The paper presents experimental results conducted on three samples of a PN SN10000 DN150 PN10 pipe buried in three different types of terrain: neutral, acidic, basic. They were subjected to axial load, measuring the force applied deformation force function. On the basis of the calculation formulas determined rigidity of the pipeline, the deformation speed of 50 mm / min. This concludes the type of land affects the rigidity of the pipe so its length of life decreases to that provided by suppliers in order to be taken compensatory measures in this regard such as choosing a higher class of pressure and stiffness pipeline than those arising discounted. This will allow for long-term value (50 years) in the mechanical characteristics sufficient for safe operation.