在建立受非均布线形荷载作用的地基力学模型的基础上,应用叠加原理推导出地基表面在非均布的线形荷载作用下,预应力锚索-地梁结构中垂直于梁轴线平面内的地基中深 处的应力和位移计算公式,为研究预应力锚索-地梁结构在岩体中的传力规律提供了理论基础。以湖南省常张高速公路K123+160~K123+369边坡为试验区域,通过理论分析得出,在对锚索施加预应力后,锚索预应力通过地梁传递给被加固的岩土体,其传递方式在垂直于地梁轴线的平面内是以梁轴线与该平面的交点为端点的近似橢圆的等值面形式由内向外呈逐渐衰减趋势分布的。现场试验得出,两地梁周边岩体中的压应变随深度增加由小到大增至峰值,然后逐渐衰减为0,这种分布形式与理论结论一致。
This paper is inclined to introduce our study of the force transmission law of a prestressed anchor-rope and the groundsill structure in rock mass by taking the slope of K123 + 160 - K123 + 369 of Changde-Zhangjiajie Expressway, Hunan, as a case of our experimental region. First of all, we have established the foundation mechanical model of non-linear unipoium load under the premise of the ground surface suffering non-linear unipoium load, which is deduced by the superposition principle, and then obtained the calculating formula for the stress and displacement at the depth z in the foundation of the axis of the beam to the prestressed anchor-Rope and groundsill structure. In so doing, we have laid a theoretical basis for studying the force transmission law. It can be concluded that the theoretical analysis is expected to make it clear that, after the anchor cable is prestressed, the actual prestress in the prestressed cable anchor would be transferred to the strengthening geotechnical body through the ground beam, whose transfer mode tends to get decaying bit by bit from the inside to the outside in the form of approximate ellipse isosurface with the endpoints being the intersection of the beam axis and the plane which are perpendicular to the axis of the beam. And, in deed, the field experiment has enabled us to get the result that the compressed strain in the peripheral rock of two ground beams tends to increase with the depth of the anchor, and then tends to get decayed gradually and finally tends to zero after reaching its peak value. This distribution form turns out to be in accordance with our theoretical analysis.