鋼筋混凝土樑受火害後之溫度與力學性質破壞之研究

Reinforced Concrete Beam of Mechanical Properties and Failure after Fire Damage

歐陽平(Ping OuYang)

指導教授 ： 林誠興

元智大學/工程學院/機械工程學系/碩士(2012年)

https://doi.org/10.6838/YZU.2012.00345

摘要

近年來，人口不斷增加使得建築物不斷增建，建築物一旦發生火災往往造成財物損失、人員傷亡等等，而鋼筋混凝土為現今相當廣泛之建築材料，鋼筋混凝土在結構上會大量使用樑、柱、樓板或牆壁，而樑在結構系統中主要是承受撓曲彎矩及剪力之構件。本研究為探討鋼筋混凝土樑受火害後之力學性質變化，其力學性質包括混凝土抗壓強度、彈性模數、鋼筋降伏強度等等，這些力學性質會因火場中高溫侵蝕而導致鋼筋混凝土內部強度之折減，強度折減至一定的程度時混凝土將發生破壞。為了精確分析鋼筋混凝土樑受火害後高溫傳至內部之情形，本研究使用FDS(Fire Dynamics Simulation)火場熱流分析軟體模擬火災中之熱流場，將其模擬結果之溫度邊界套入PHOENICS計算流力分析軟體進行樑內部溫度與力學性質計算，並與文獻做驗證以符合模擬之精確性，最後將計算樑之破壞模式，以評估樑受火害後其結構強度，以及能否繼續使用。

關鍵字

火害 ； FDS ； 鋼筋混凝土樑

並列摘要

In recent years, the population continues to increase make the building continue to build more buildings. When building fire happened, it usually caused properties loss, casualties and so on. Reinforced concrete nowadays is a generally of building materials. Reinforced concrete structure will be a large number of beams, columns, floor or wall. Beam structural system to withstand the bending moment and shear component. Therefore, this research is investigation of reinforced concrete beams by the mechanical properties change after fire damage. The mechanical properties include concrete compressive strength, modulus of elasticity, steel yield strength and so on. These mechanical properties due to fire and high temperature erosion cause by the internal strength reduction of reinforced concrete. Strength reduced to a certain extent so that the reinforced concrete will induce destruction. For accurate analysis of reinforced concrete beams after the fire and the situation of high temperature transmitted to internal. This research used the FDS (Fire Dynamics Simulation) which is fire heat flow analysis software simulation heat flow field in the fire. The FDS simulation result of temperature boundary set into PHOENICS which is computational fluid dynamics software for analysis beams internal temperature and mechanical properties, then validation with the literature to conform simulation accuracy. Finally, compute the failure mode of beams to assessment structural strength after fire, and whether it can continue to use.

並列關鍵字

Fire Damage ； FDS ； Reinforces Concrete Beam

參考文獻

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[40]徐瑞祥、林誠興，「鋼筋混凝土樑受火害後之撓曲能力數值模擬」，技師月刊，Vol. 36，pp. 96-103，2005。

[42]黃彰斌、林誠興、徐瑞祥，「鋼筋混凝土樑受火害時之溫度分佈與殘餘強度分析」，技術學刊，Vol. 21, No. 2, pp. 175-188, 2006。

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