无机胶较有机胶具有良好的耐高温性能,进行火灾后无机胶植筋的拉拔试验研究对完善后锚固技术规范具有重要的理论意义.文章研究了不同钢筋直径、不同植筋深度的构件的拉拔承载力及其破坏形态,分析了各个植筋试件拉拔极限承载力及承载力损失,阐明了植筋深度、钢筋直径与拉拔承载力的关系.结果表明:火灾后试件在植筋深度为15 d和20 d时,试件发生钢筋的滑移破坏;当植筋深度为22 d时,试件为钢筋的颈缩破坏.在钢筋直径一定时,植筋深度为15 d或20 d时,其高温后的极限拉力较常温下均折减50%以上;随着植筋深度的增加,混凝土内部温度场逐渐递减,高温后的极限拉拔承载力随二者变化呈增长趋势,高温后的极限拉力呈增长趋势,且锚固长度越长极限拉力增加愈明显.%Inorganic adhesive with organic adhesive has good performance of high temperature resistance, and fire inorganic anchoring adhesive tensile experiment has important theoretical significance. to improve anchorage technology standard. This paper made a research on the normal temperature inorganic adhesive anchorage drawing bearing capacity,for different bar diameter(14 mm, 16 mm,22 mm),different anchorage depth(15 d,20 d,22 d)of the member. By summarizing its failure mode analysis and comparing each specimen drawn anchorage ultimate bearing capacity and the loss of capacity,the paper derived the relationship between anchorage depth,bar diameter and pull bearing capacity. The results show that:when the specimen after the fire with has the anchorage depth of 15d and 20d,reinforced specimen slippage occurs;when the anchorage depth is 22d,the specimen reinforced necking destruction. When the bar diameter is constant and the anchorage depth is 15d or 20d,its high temperature limit tension after reduction than the room temperature was above 50%;With the increase of the depth of embedded steel bars,concrete internal temperature field is gradually decreasing,after high temperature of the ultimate tensile bearing capacity an increasing trend over the two changes,and the longer the length of anchoring the more obvious the ultimate pullout capacity increases.
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