Evaluation of the condition of the external layer of walls in the national technological system "S-Sz" (Szczecin System) of large-panel prefabricated construction

Poznan University of Technology, Pl. Marii Skłodowskiej-Curie 5, 60-965 Poznan

^* Corresponding author: krzysztof.f.girus@doctorate.put.poznan.pl

Abstract

The condition of the texture layer of external walls directly affects the durability of a large panel building. The results presented in the article are the result of an inventory and a number of studies carried out in 2018 on selected residential buildings in a local variant of the Szczecin Large-Panel System. Both in situ tests (layer thickness measurement, reinforcement location, determination of lagging thickness) and laboratory tests (strength test, carbonation range) were carried out. Significant deviations of the examined wall elements from the design assumptions were proved. Moreover, it was found that the carbonated concrete of the external layer does not adequately protect reinforcing steel. With the use of so-called sandwich samples, the compressive strength of the concrete was confirmed. A favourable ratio of specimen dimensions was established for the results of lightweight concrete strength tests.