锚索框架梁加固公路滑（边）坡的预警技术研究
发布时间：2018-09-05 17:20
【摘要】：自西部大开发战略开展以来,陕西高速公路发展迅速,由于陕北黄土沟壑区和陕南秦巴山区的地形、地貌和地质条件比较复杂,高速公路沿线分布着大量古滑坡体以及因公路施工产生的新滑坡体,工程处治滑(边)坡路段的稳定性已成为影响高速公路安全运行的关键因素。锚索框架梁作为一种新型支护体系,已广泛应用到高速公路滑(边)坡加固中,但是其理论研究远滞后于工程实践,而且研究重点集中在内力计算方法、设计方法、数值模拟及模型试验等上,缺少对其预警判据的研究。本文以陕西高速公路沿线典型工程处治滑(边)坡路段为研究对象,以滑(边)坡岩性和锚索框架梁的实际破坏形式为研究依据,将预警判据分为锚固力判据和框架位移判据进行研究,锚固力判据又可分为极限抗拔力判据和锚固力阈值判据,然后基于设计理论,拟合并推导出锚固力阈值和框架位移阈值的计算公式,从而建立起锚索框架梁的预警判据式,并利用实例证明了所建判据的合理性;以“示范工程”为参照,提出了高速公路工程处治滑(边)坡的监测预警技术。主要得到以下成果:(1)以锚索极限抗拔力的传统计算公式为基础,建立了相应的锚固力预警判据式;分别基于Winkler地基模型和Pasternak地基模型,在锚固力相同的情况下,首先确定了最大弯矩位置与悬臂端长度临界值的关系,并利用软件拟合出长度临界值的计算公式,然后推导出锚固力阈值的计算公式;在锚固力不同的情况下,根据框架梁上最大锚固力位置的确定与否,分情况对锚固力阈值的计算方法进行了研究,建立相应的预警判据。(2)基于Winkler地基模型和Pasternak地基模型,在锚固力相同的情况下,推导出框架位移与弯矩的关系式,并取梁端与梁中节点处最小位移作为位移阈值;在锚固力不同的情况下,拟合出框架位移阈值与结构能承受的最大弯矩、基床系数、(剪切模量)、混凝土弹性模量等参数的关系式,从而建立预警判据式;通过比较分析基于两种模型建立的判据,发现Pasternak地基模型用于滑(边)坡的预警预报更为合适。(3)针对锚索框架梁加固的公路滑(边)坡,提出了相应的监测方案,并提出了锚索框架梁监测点的布置方案;基于监测方案,提出了滑(边)坡稳定性评价指标,并且对高速公路工程处治滑(边)坡进行了预警等级划分,共分为黄、橙、红三级,同时提出了相应的应对措施。
[Abstract]:Since the development of the western development strategy, the highway in Shaanxi has developed rapidly. Because of the complicated topography, geomorphology and geological conditions in the loess gully region of northern Shaanxi and the Qinba mountainous area in southern Shaanxi, There are a large number of ancient landslide bodies along the highway and the new landslide body caused by the highway construction. The stability of the landslide section has become the key factor that affects the safe operation of the highway. As a new type of support system, anchor cable frame beam has been widely used in highway slope reinforcement, but its theoretical research lags far behind engineering practice, and the research emphasis is on internal force calculation method and design method. In numerical simulation and model test, there is a lack of research on its early warning criterion. In this paper, the typical projects along the Shaanxi Expressway are taken as the research object, and the lithology of the slope and the actual failure form of the anchor cable frame beam are taken as the research basis. The early warning criterion is divided into anchor force criterion and frame displacement criterion. The anchor force criterion can be divided into limit pullout force criterion and anchor force threshold criterion, and then based on design theory, The formulas of anchor force threshold and frame displacement threshold are deduced to establish the early warning criterion formula of anchor cable frame beam, and the rationality of the established criterion is proved by an example. This paper puts forward the monitoring and early warning technology of highway engineering for the treatment of slippery (edge) slopes. The main achievements are as follows: (1) based on the traditional calculation formula of ultimate uplift resistance of anchor cable, the corresponding early warning criterion formula of anchoring force is established, respectively, based on Winkler foundation model and Pasternak foundation model, under the same anchoring force, The relationship between the position of the maximum bending moment and the critical value of the length of the cantilever end is first determined, and the formula for calculating the critical value of the length is fitted by software, and then the formula for calculating the threshold value of the anchoring force is derived. According to the determination of the position of the maximum anchoring force on the frame beam, the calculation method of the anchor force threshold is studied, and the corresponding early warning criterion is established. (2) based on the Winkler foundation model and the Pasternak foundation model, under the same anchoring force, the anchoring force is the same. The relationship between frame displacement and bending moment is derived, and the minimum displacement at the end of beam and the node in beam is taken as the displacement threshold. The relationship between the parameters of the bed coefficient (shear modulus) and the elastic modulus of concrete is used to establish the early warning criterion, and the criterion based on the two models is compared and analyzed. It is found that Pasternak foundation model is more suitable for early warning and prediction of sliding (edge) slope. (3) the corresponding monitoring scheme is put forward for the slope of highway reinforced by anchor cable frame beam, and the layout scheme of monitoring point of anchor cable frame beam is put forward. Based on the monitoring scheme, the evaluation index of slope stability is put forward, and the early warning grade is divided into three grades: yellow, orange and red, and the corresponding countermeasures are put forward.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U418.55
[Abstract]:Since the development of the western development strategy, the highway in Shaanxi has developed rapidly. Because of the complicated topography, geomorphology and geological conditions in the loess gully region of northern Shaanxi and the Qinba mountainous area in southern Shaanxi, There are a large number of ancient landslide bodies along the highway and the new landslide body caused by the highway construction. The stability of the landslide section has become the key factor that affects the safe operation of the highway. As a new type of support system, anchor cable frame beam has been widely used in highway slope reinforcement, but its theoretical research lags far behind engineering practice, and the research emphasis is on internal force calculation method and design method. In numerical simulation and model test, there is a lack of research on its early warning criterion. In this paper, the typical projects along the Shaanxi Expressway are taken as the research object, and the lithology of the slope and the actual failure form of the anchor cable frame beam are taken as the research basis. The early warning criterion is divided into anchor force criterion and frame displacement criterion. The anchor force criterion can be divided into limit pullout force criterion and anchor force threshold criterion, and then based on design theory, The formulas of anchor force threshold and frame displacement threshold are deduced to establish the early warning criterion formula of anchor cable frame beam, and the rationality of the established criterion is proved by an example. This paper puts forward the monitoring and early warning technology of highway engineering for the treatment of slippery (edge) slopes. The main achievements are as follows: (1) based on the traditional calculation formula of ultimate uplift resistance of anchor cable, the corresponding early warning criterion formula of anchoring force is established, respectively, based on Winkler foundation model and Pasternak foundation model, under the same anchoring force, The relationship between the position of the maximum bending moment and the critical value of the length of the cantilever end is first determined, and the formula for calculating the critical value of the length is fitted by software, and then the formula for calculating the threshold value of the anchoring force is derived. According to the determination of the position of the maximum anchoring force on the frame beam, the calculation method of the anchor force threshold is studied, and the corresponding early warning criterion is established. (2) based on the Winkler foundation model and the Pasternak foundation model, under the same anchoring force, the anchoring force is the same. The relationship between frame displacement and bending moment is derived, and the minimum displacement at the end of beam and the node in beam is taken as the displacement threshold. The relationship between the parameters of the bed coefficient (shear modulus) and the elastic modulus of concrete is used to establish the early warning criterion, and the criterion based on the two models is compared and analyzed. It is found that Pasternak foundation model is more suitable for early warning and prediction of sliding (edge) slope. (3) the corresponding monitoring scheme is put forward for the slope of highway reinforced by anchor cable frame beam, and the layout scheme of monitoring point of anchor cable frame beam is put forward. Based on the monitoring scheme, the evaluation index of slope stability is put forward, and the early warning grade is divided into three grades: yellow, orange and red, and the corresponding countermeasures are put forward.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U418.55
【参考文献】
相关期刊论文 前10条
1 宋占璞;施斌;汪义龙;严s，
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