A glulam beam with the size of 4700 mm×300 mm×480 mm(L×W×H) was tested in the furnace to investigate the fire resistance performance of glulam beam according to the temperature curve of ISO834. Thr...A glulam beam with the size of 4700 mm×300 mm×480 mm(L×W×H) was tested in the furnace to investigate the fire resistance performance of glulam beam according to the temperature curve of ISO834. Three surfaces, the bottom and the two flanks, of the glulam beam were exposed to fire in the test. Simply supported bearings were used to support the beam on which the load of 0.76 kN/m was uniformly set. The experimental results show that: 1) Sectional dimension of glulam beam was greatly diminished due to the serious decomposition and carbonization of the timber. 2) The largest vertical deformation is relatively small and it has not exceeded 3.95 mm until the end of experiment. The maximum temperature on the top surface of the glulam beam attains 180 ℃ at 3437 s, which indicates that the beam have failed according to the European standard of fire resistance tests. 3) The right end of the beam with 16 connecting holes(the connecting holes were used for the connection between bolt and column) and the slit in the beam both burnt intensely and carbonized seriously because the fire could reach the holes and slit of beam facilitating the burning.展开更多
Twenty tests were conducted to investigate the efficiency of the intumescent coating designed to protect steel plate at the elevated temperature, by means of electrical furnace. And the factors of the initial thicknes...Twenty tests were conducted to investigate the efficiency of the intumescent coating designed to protect steel plate at the elevated temperature, by means of electrical furnace. And the factors of the initial thickness of coating and temperature of electrical furnace were considered. The high temperature response behavior of the intumescent coating was observed. And the expansion form of ultrathin intumescent coating and the temperature of the steel plate(TS) were obtained. Besides, the heat flux from expansion layer to steel plate versus time was analyzed in order to evaluate the heat transfer effect of intumescent coating on steel plate. The experimental results show that the response behaviors of the coating subjected to fire could be divided into four phases: stabilization phase, foaming expansion phase, carbonization-consumption phase and inorganic layer phase. And the net heat flux to the steel plate decreased observably in the foaming expansion phase, while the surplus white inorganic substance, which is the residue of the intumesced char layer in the inorganic layer phase under the condition of the temperature of the electrical furnace(TEF) beyond 700 °C over 1 h, has little effect on fire protection for the steel plate.展开更多
基金Projects(51576212,51534008)supported by the National Natural Science Foundation of ChinaProject(2016YFC0802501)supported by the National Key Research and Development Program of ChinaProject(KFKT2014ZD02)supported by the Open Fund of Key Laboratory of Building Fire Protection Engineering and Technology of Ministry of Public Security,China
文摘A glulam beam with the size of 4700 mm×300 mm×480 mm(L×W×H) was tested in the furnace to investigate the fire resistance performance of glulam beam according to the temperature curve of ISO834. Three surfaces, the bottom and the two flanks, of the glulam beam were exposed to fire in the test. Simply supported bearings were used to support the beam on which the load of 0.76 kN/m was uniformly set. The experimental results show that: 1) Sectional dimension of glulam beam was greatly diminished due to the serious decomposition and carbonization of the timber. 2) The largest vertical deformation is relatively small and it has not exceeded 3.95 mm until the end of experiment. The maximum temperature on the top surface of the glulam beam attains 180 ℃ at 3437 s, which indicates that the beam have failed according to the European standard of fire resistance tests. 3) The right end of the beam with 16 connecting holes(the connecting holes were used for the connection between bolt and column) and the slit in the beam both burnt intensely and carbonized seriously because the fire could reach the holes and slit of beam facilitating the burning.
基金Project(12JJ2033)supported by the Hunan Provincial Natural Science Foundation of ChinaProject(KFK2014ZD02)supported by the Key Laboratory of Building Fire Protection Engineering and Technology of MPS,ChinaProject supported by the Fundamental Research Funds for the Central Universities of Central South University,China
文摘Twenty tests were conducted to investigate the efficiency of the intumescent coating designed to protect steel plate at the elevated temperature, by means of electrical furnace. And the factors of the initial thickness of coating and temperature of electrical furnace were considered. The high temperature response behavior of the intumescent coating was observed. And the expansion form of ultrathin intumescent coating and the temperature of the steel plate(TS) were obtained. Besides, the heat flux from expansion layer to steel plate versus time was analyzed in order to evaluate the heat transfer effect of intumescent coating on steel plate. The experimental results show that the response behaviors of the coating subjected to fire could be divided into four phases: stabilization phase, foaming expansion phase, carbonization-consumption phase and inorganic layer phase. And the net heat flux to the steel plate decreased observably in the foaming expansion phase, while the surplus white inorganic substance, which is the residue of the intumesced char layer in the inorganic layer phase under the condition of the temperature of the electrical furnace(TEF) beyond 700 °C over 1 h, has little effect on fire protection for the steel plate.
