滚石灾害是西部山区常见的一种地质灾害,工程实践表明,在滚石防护结构上设置垫层材料能有效地减轻滚石的冲击力,而滚石冲击力是滚石防护结构设计的关键荷载,目前国内外尚无合理的计算公式,严重地影响了滚石防护结构的应用。在以典型滚石防护结构为原型,根据球形压模压入半空间基本理论,在假设垫层材料为理想弹塑材料的基础上,研究了垫层材料的冲击特性,推导了滚石冲击压力计算公式,为滚石防护结构设计提供合理的冲击力计算公式。结果表明:在考虑垫层材料的实际弹塑性特征时,计算出的滚石冲击压力远小于由完全弹性碰撞理论确定的冲击压力值;垫层材料能有效地减轻滚石对防护结构的冲击作用。
Rock-fall is a frequent disaster in western mountainous regions. Engineering practice shows that the compact pressure of rock-fall can be reduced effectively through setting cushion materials on the rock-fall shield structure. The compact pressure of rock-fall is the governing loading in the design of rock-fall shield structures, which, nevertheless, cannot be calculated accurately, resulting in a haltered application of the rock-fall shield structure. Taking a typical rock-fall shield structure as a prototype, based on the rigid sphere punch half-space theory and perfectly elastic-plastic assumption, the paper studied the compact characteristics of cushion materials and deduced the formula to calculate the compact pressure of rock-fall. The study provided a reasonable compact pressure calculation formula for the shield structure design. Results showed that: considering the structure's elastic-plastic properties, the actual normal impact pressure was far less than the rock-fall impact pressure calculated under the full elastic impact theory; the cushion materials on the rock-fall shield structure could reduce the compact pressure effectively.