Thermal irregularity of connection joints in modular enclosing structures

The object of research is the thermal irregularity (non-uniformity) of connection joints in modular enclosing structures. The purpose of this work is a comprehensive study of the thermal properties of enclosing structures of modular buildings. Method. The study combines full-scale temperature measurements on a modular corner fragment with three-dimensional finite element thermal modeling. Numerical modeling of two typical configurations of corner joints was also carried out: with hollow square sections and with I-beams. Results. The analysis of heat losses at the junctions of structural elements was conducted. The validated model reproduces the experimentally observed temperature distribution, confirming its suitability for analyzing thermal irregularities. The strongest cooling and highest heat flux occur in the wall-floor corner zone due to geometric and material discontinuities. Comparative assessment of joint configurations shows that hollow square profiles exhibit lower specific heat losses (0.008 W/°C) than I-beam joints (0.011 W/°C), indicating their higher thermal efficiency.