Probabilistic Analysis of Thermal Performance of the Wall From Light-Gauge Thin-Walled Steel Structures

Abstract

The article is devoted to determining of the thermal reliability rates of CFS wall panels based on three thermo-technical failure criteria - reduced heat transfer resistance, exceeding the values of the temperature difference between the reduced temperature of the inner surface of structure and internal air temperature above the permissible temperature values by the sanitary requirements and criteria of reduction of local values of the inner surface temperature to the temperature of vapor-liquid condensation.
 With increasing coefficient of variation of thermal conductivity from 2.28% to 20%, the probability of refusal of wall panels of light steel thin-walled structures, under the criterion of the specified heat transfer resistance, is increasing from 9,85´10-7 to 0,015 respectively.

Standardization of Required Level Probability of No-Failure Operation of the Building Envelopes by the Criterion of Total Thermal Resistance

“…Due to the fact that the probability of materials over-consumption in the event of a change in the thickness of the structure (as compared to the thickness calculated by the effective standards) is equal to 1, the risk of expenses on the additional increase in the thickness of the protective structure R C will be equal to the difference in the cost of the floor slab compared with the base case of the B C . ,31 4,592 0,061 0,31 0,006 25 2000 13,53 0,32 4,694 0,163 0,32 0,016 25 2000 36,08 0,33 4,796 0,265 0,33 0,026 25 2000 58,63 0,34 4,898 0,367 0,34 0,036 25 2000 81,18 0,35 5,000 0,469 0,35 0,046 25 2000 103,74 0,36 5,103 0,571 0,36 0,056 25 2000 126,29 0,37 5,205 0,674 0,37 0,066 25 2000 148,84 We calculate additional heat consumption through the building envelope ΔTB Q by formula (9). For Poltava, the number of heating degree-days is Dd = 3702.4.…”

“…They proposed methods for numerical estimation of the probability of homogeneous building envelopes failure upon the following criteria: failure to achieve a sufficient level of thermal resistance due to the variability of geometrical and thermophysical characteristics of building envelope materials; exceeding the maximum permissible value of the heat flow density through the building envelope. Further research in the field of thermal reliability of building envelopes, and walls made from thin-walled steel structures in particular, was carried out in PoltNTU [5][6][7][8][9]. Thermotechnical research on building envelope was also done in [10][11][12][13][14][15][16]18].…”