包覆填充式箱型鋼管混凝土柱火害行為研究

Abstract

火災可能導致建築結構損壞或倒塌，嚴重危害人員生命安全與公共安全。柱構件為主要支撐建築物之結構構件，因此柱構件在建築防火設計有其重要性。近年來，國內高樓建築普遍採用鋼骨鋼筋混凝土構造，在工程實務上，常於鋼骨鋼筋混凝土柱構件配置剪力釘，然而設計規範因可採強度疊加觀念未要求柱構件之鋼骨配置剪力釘。由以往內灌混凝土箱型柱(Concrete Filled Box Column, CFBC)火害研究成果發現，CFBC承受軸向載重時，因不同材料性質導致強度損失及熱膨脹能力有所差異，此差異現象可能會影響CFBC構件耐火能力。除軸向載重外，剪力釘於柱構件耐火性能與破壞模式將扮演重要角色。此方面研究甚為缺乏，因此，本研究將以實驗方法與分析方法探討設計參數於CFBC耐火性能的影響。

預期目標： 1. 利用承重與高溫實驗結果建立箱型鋼管混凝土柱設計參數於耐火能力之影響。 2. 利用分析方法模擬實驗行為並與試驗結果驗證，建立箱型鋼管混凝土柱設計參數之耐火能力之模型。 3. 鋼骨鋼筋混凝土結構設計規範耐火性能設計專章單一構件部分具體條文研訂。 4. 以結構耐火的角度量化設計規範中剪力釘配置與數量，並據以修訂「鋼骨鋼筋混凝土構造設計規範與解說」中相關設計內容並加以解說。 5. 針對建築技術規則建築設計施工編防火構造中，包覆型(鋼骨在外)混凝土柱之防火時效進行實質驗證，提供營建署修訂相關條文時之參考。 6. 提供工程實務上應用，可供鋼骨鋼筋混凝土結構火害後承載能力之評估

Fire may cause structural damage or collapse, and seriously endanger the human and public safety. Columns are main supporting members in structural system, thus the columns play an important role in the fire safety. In recent years, the steel reinforced concrete (SRC) structures are frequently used for medium- and high-rise buildings in Taiwan. In engineering practice, shear studs are usually placed for SRC members. However, the shear studs are not needed according to the design specification, considering the strength superposition. Test results of previous research in concrete filled box columns (CFBCs) indicate that CFBCs were observed to have discrepancy in the strength and thermal expansion due to the different material while CFBCs subjected to axial compression. The discrepancy may affect the fire resistance of the CFBCs. In addition to the axial compression, shear studs may play an importance role in the fire resistance and failure mode. Due to lack of the literature research data, this research will be conducted experimentally and numerically to investigate the effect of the design parameters on the fire resistance of CFBCs.

Prospective goals of this project are as follows. 1. To establish the effect of design parameters on fire resistance of concrete filled box columns via loading test at elevated temperature. 2. To establish numerical model of the design parameters on fire resistance through numerical analysis to simulate and validate the experimental results. 3. To develop the draft of fire resistance for concrete filled box column for the current SRC specifications. 4. To quantify the design of shear studs for the CFBCs based on fire safety design. 5. To provide the reference for fire resistance of CFBCs to amend the current architecture design and constructions codes. 6. To provide application for engineering practice to evaluate the loading capacity of SRC after fire.