钢筋混凝土梁抗火性能及加固试验研究-防灾减灾工程及防护工程专业论文.docxVIP

In In this paper,based on reinforced concrete beams as research objects，the dint properties of structure after strengthen have been studied in the tests，and its fire-resistance behaviors and dint behaviors of augmented僦tion are analyzed and discussed with the method of theoretical analysis and numerical calculation together．硼1c main contents inchde： (1)Considering the thermal properties of concrete,the finite difference equation and formula arc built for the temperature of reinforced concrete beams with safeguard under three side exposing to fire．11把program is developed to compare、)l，ith the test results．The computer results shows that，the safeguard can reduce the speed of thermal transfer to the concrete and rebar,delay the time of heightening temperature and reduce intensity,then enhance its fire-resistance behaviors． f2)The experiments of SeVen reinforced concrete beams under fire and one beam in common temperature are accomplished．11艟 deformation characteristic and damage form of members are investigated through the tests．111e influences for its fire-resistance behaviors of constant loads and times exposed to fire are researched and discussed． (3)The tests oftwo reinforeed concrete beams under loads after fire have been carried out．耶1c macroscopical phenomena,damage fcamres and deformation mles of the members are studied，and the drop degree of the bearing capacity is compared and analyzed．The results shows that the concrete beams Was damaged serious by fire,and the damage is serious、jl，ith bigger loads and longer time exposed to fire． (4)Five concrete beams damaged by fire are strengthened with self-compacting concrete．The experiments of the beams after repmred are accomplished,the influences for its dint behaviors of constant loads and repmfing thickness are researched and discussed．啊1e beating capacity of the strengthened reinforced concrete is compared and analyzed with the method of section grid．A simplified method for H calculating calculating the resid