摘要
因预应力锚索锚固力损失而导致锚固失效的工程事故屡屡发生,锚索锚固力损失与岩土体蠕变之间存在复杂的耦合效应关系,建立二者之间的耦合效应模型,确立二者之间的计算关系式,为预应力锚固工程的设计、施工、安全运行管理以及锚固力损失的控制与补偿技术提供理论基础和技术手段。通过理论分析和模型研究,在岩土体常用流变模型基础上建立了基于应变相等的耦合效应计算模型,并进行了模型验证。研究结论:(1)建立了与工程实际相符合的锚索锚固力变化和岩土体蠕变的耦合效应计算模型,正确反映了预应力锚索锚固力损失和岩土体蠕变之间的关系,推导出了其本构方程、松弛方程和蠕变方程,从理论上解决了锚固力变化与岩土体蠕变之间的计算关系。(2)通过耦合效应计算模型的蠕变方程,在材料参数已知的情况下,可以计算出边坡蠕变影响引起的锚索锚固力损失量,并结合实际工程中监测到的锚索应力数据进行对比分析,就能够准确地了解、评价锚索锚固力的异常变化情况,指导实际工程中的设计和施工,保证工程建设过程中的安全性。(3)通过耦合效应计算模型的松弛方程,可以对预应力锚索受力状态的监测数据进行分析整理,通过对锚索锚固力损失量的数据进行反分析,分析岩土体的蠕变参数,根据蠕变介质的材料特性,计算岩土体蠕变量,根据蠕变量判断预应力锚索锚固工程的安全性和可靠性,指导锚固工程的安全运行管理。
The engineering accidents of anchorage failure often occur owing to the loss of anchorage force of prestressed anchor cable. Complicated coupling effect exists between the anchorage force loss of anchor cable and rock and soil creep. Theoretical foundation and technical means for the design, construction, safe operation management, the control and compensation technique of the loss of anchorage force is provided by building the coupling effect model and establishing the formula of the two. On the basis of common rheological model of rock and soil, coupling calculation model is established based on the equal strain and validated as well by means of theoretical analysis and model research. The findings are as follows: (1) The coupling effect model of anchor cable anchorage force change and rock and soil creep in line with the practical engineering is established. The relationship between the anchorage force loss of prestressed anchor cable and rock and soil creep is correctly reflected. The constitutive equation and relaxation equation and creep equation are deduced, and the calculable relationship between anchorage force change and rock and soil creep is solved theoretically. (2)With the creep equation of the coupling calculation model, the anchorage force loss of anchor cable caused by slope creep effect can be calculated when the material parameters are known. Comparatively analyzing the anchor cable stress data in the practical engineering, we can accurately understand and evaluate the abnormal changes of anchor cable anchorage force to guide the design and construction of practical engineering and ensure the safety of engineering construction process. (3) With the relaxation equation of coupling calculation model, the monitoring data of prestressed anchor cable stress state is arranged and analyzed. With the back analysis of the anchorage force loss data of anchor cable, the creep parameters of rock and soil are analyzed. The creep value of rock and soil according to the material characteristics of creep medium is calculated. The safety and reliability of prestressed anchor cable anchorage engineering are judged in accordance to the creep value to guide the safety operation management of anchorage engineering.
出处
《岩土力学》
EI
CSCD
北大核心
2014年第8期2150-2156,2162,共8页
Rock and Soil Mechanics
基金
国家自然科学基金(No.41372289)
山东省高等学校科技计划项目(No.12LH03)
中国博士后科学基金(No.2012M521365)
山东科技大学科研创新团队支持计划资助
关键词
锚固力损失
蠕变
耦合效应
计算模型
loss of anchorage force
creep
coupling effect
calculation model