Started from the analysis of connection form between prop end and pit on top beam and quantified calculation to analyze the cause of prop end deformation,points out the defect for design.

• 从分析立柱柱头与顶梁柱窝的结构形式入手,采取定量计算的方法分析了引起桩头变形的原因,指出了设计上存在的缺陷。