Abstract: Deficiencies of the commonly-used calculation model of the rock slope reinforced by prestressed anchor gridiron beam were analyzed. The Winkler foundation model was appropriate in calculating internal force of gridiron beam. Based on the regression analysis of test data, regressive formulas to estimate coefficient of subgrade reaction for uniaxial compressive strength of rock under natural condition were given. Based on Winkler foundation model theory, the simplified calculation method of internal force of gridiron beam was obtained through theoretical analysis and calculation. The result indicates that the reaction distribution of prestressed anchor gridiron beam on rock slope is uneven, and the reactions tend to concentrate under the anchor nodes. Interaction of gridiron beam and slope rock mass should be considered when calculating reaction and internal force of gridiron beam. Compared with the conventional design method, the simplified calculation method based on Winkler foundation model theory is more reasonable and economical, in which the cross-section size and reinforcement ratio of gridiron beam are optimized by over 30%, which can provide reference for optimum design of this type of support structure.

Key words: geotechnical engineering, rock slope, gridiron beam, Winkler foundation model, coefficient of subgrade reaction

摘要： 分析了预应力锚杆框格梁加固岩质边坡时常用计算模型，指出采用文克尔地基模型对岩质边坡框格梁的内力进行分析计算是适当的；通过对试验数据的回归分析，给出了天然状态下岩石单轴抗压强度换算基床系数的回归公式；基于文克尔地基模型理论，通过理论分析计算，得出了框格梁内力简化计算方法。研究表明：岩质边坡上的预应力框格梁反力分布不均匀，其反力呈锚杆结点下集中的趋势，实际在进行框格梁梁底反力和内力计算时，应考虑框格梁与边坡岩体的相互作用；与常规设计方法相比，基于文克尔地基理论得出的简化计算方法更加合理经济，截面尺寸和配筋率优化达到30%以上，可为该类型支护结构优化设计提供参考。

关键词: 岩土工程, 岩质边坡, 框格梁, 文克尔地基模型, 基床系数