为了研究复杂动力环境及化学作用下受腐蚀疲劳损伤预应力锚索的安全可靠性,采用现场取样,选取不同腐蚀程度的预应力锚索观察其腐蚀状态,在实验室进行拉伸破坏试验,测得不同腐蚀程度下的锚索强度、拉伸值,并建立增量理论本构方程,结合腐蚀损伤模型,揭示塑性条件下瞬时应力锚索持续应变与损伤部位应力集中破坏过程.研究结果表明,锚索珠状腐蚀状态下索体周围地质动力作用最为剧烈;当预应力锚索腐蚀程度达到8.21％以上时,锚索脆性现象明显,此时锚索索体延展性极小,在巷道中后期锚索腐蚀使得拉伸能力减弱;深部矿井循环瞬时动力作用会使得锚索周围产生滑移带,增加锚索塑性拉伸值,该种应力状态下索体腐蚀比单一化学腐蚀程度更为剧烈,当腐蚀程度使得索体达到脆性状态时,锚索强度降低15％以上,拉伸值降低86.4％以上,锚索依靠伸缩吸能防冲效果会在支护中后期失效.%In order to study a safety reliability of a pre-stressed anchor with a corrosion fatigue and damage under complicated dynamic environment and chemical function,tensile failure tests were conducted in lab on the site samples and the selected pre-stressed anchors and the corrosion status of anchors were observed.The strength and tensile value of anchors with different corrosion degree were measured and were applied to establish a constitutive equation of incremental theory.In combination with the corrosion damage model,sustained strain of transient stress anchor and the stress concentrated failure process of damage part under plastic condition were revealed.The study results showed that under dropwise corrosion status of anchors,the dynamic geological effect around anchor body would be serious.When the corrosion degree of pre-stressed anchor was over 8.21％,the brittle phenomenon of anchor would be obvious.At the moment,the extension of anchor body would be minimal.At the middle and late period of mine roadway,the anchor corrosion would make tensile capacity reduced.The transient dynamic effect of deep mine circulation would cause sliding zone around the anchor and the plastic tensile value of anchor would be increased.Under the stress status,the corrosion of anchor body would be more serious than single chemical corrosion degree.When the corrosion degree caused anchor body in a brittle status,the strength of anchor would be reduced over 15％,the tensile value would be reduced over 86.4％ and the bump prevention effect of anchor with expansion and energy absorption function would be failure in the late support period.
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