| Popis: |
The authors conducted an ISO 13785-2 modified large-scale facade fire tests in Tokyo University of Science and tentatively proposed the draft for the calculation method for vertical upstairs fire spreading based on those fire test results, prior to this study. And in this research, several modifications were carefully added to past calculation methods, especially regarding the calculation of temperature in the fireroom, detailed method of unifying multiple openings on the same floor for calculation, and the criteria for the occurrence of upstairs fire spreading. Detailed calculation methods are proposed for two different situations depending on the existence of an eave above the opening at the fireroom, respectively. Also, two different criteria for verification of vertical upstairs fire spreading were proposed, one of which is based on the maximum heat flux to the upstairs room (Method 1), while the other is based on the integrated value of heat flux over time of fire duration (Method 2). Using this newly modified calculation method, the effectiveness of 90 cm spandrel and 50 cm eave is demonstrated, respectively, in terms of practically preventing the occurrence of vertical upstairs fire spreading. Improved verification calculation methods (both Methods 1 and 2) are applied to four exiting office buildings in Japan and seven rooms of fire origin considered. Verification methods using calculation proposed in this study are proved to be able to practically evaluate the occurrence of vertical upstairs fire spreading, especially regarding noncombustible facades with openings in there. |
