边坡加固机理探讨

STUDY ON MECHANISM OF SLOPE REINFORCEMENT

根据十几个岩土边坡加固工程的设计、审查和施工经验,对边坡加固中预应力锚索的传力深度、自由段概念、削坡开挖边坡安全系数、群锚形成“岩壳”、补赏张拉等问题进行了讨论。介绍了边坡治理中开挖控制变形工法,总结出施工的6项工法要素为:安全监测、超前支护、分层分段开挖、及时进行坡面支护、加强边坡底部支护和施工工艺管理。着重讨论了预应力锚索钻孔中水泥砂浆芯柱的受力分析,把问题归结为压杆稳定。并介绍了一种新型预应力锚梁结构,该结构大大提高了预应力锚索的承载力,从而使边坡达到更好的加固效果。最后,对边坡加固中的几个重要问题进行分析和探讨。

The stress transfer depth of the prestressed cable,the concept of free section,safety factor of cut slope,the so-called rock crust created by cluster anchoring and supplemental tensioning in slope reinforcement are discussed based on experiences of design,examination and construction of near twenty cases. The slope excavation method with deformation control is introduced,whose main factors include safety monitoring,advance support,cutting in layers and sections,timely slope surface support,intensified slope toe support and management of construction technique. The stress in grout stem in borehole is emphatically analyzed,and this issue is reduced to the problem of stabilization of compressed rod. The new structure of prestressed anchor beam is proposed to increase the bearing capacity of prestressed cable.