高级检索

      碎石填土单点夯击下的耗散能效计算与试验分析

      Calculation of dissipation energy efficiency and experimental analysis of gravel fill under single point ramming

      • 摘要: 为研究强夯作用下不同土体的耗散能效,及不同深度土体随夯击次数变化的能量耗散规律,通过理论推导和室内模型试验,分析土体夯沉量、土体竖向位移、夯锤加速度、持续作用时间、夯锤冲击力及土体分层加速度等数据变化规律。结果表明:①强夯地基土体的变形是耗散结构,并推导得到了耗散效能系数η计算公式。②随夯击次数的增加,夯锤对地基土体的冲击应力逐渐增大,地基土体整体的密实度逐渐增大,地基土体整体加固所耗散的能量逐渐减小;夯击能越大,夯锤与土体作用的持续时间越长,整体密实度越大,土体自身加固耗散的能量越多。③随夯击次数的增加,地基上部土体自身加固耗散的能量先逐渐减小,而后保持稳定,最后逐渐增加;中部土体自身加固耗散的能量先逐渐减小,最后保持稳定;下部土体自身加固耗散的能量逐渐减小,但相对于上部、中部土体而言,传播至下部土体的能量较小,密实度增加的速率较小,自身加固耗散能量的减小速率较小,未达到稳定状态。

         

        Abstract: To study the energy dissipation efficiency of different soil types under dynamic compaction and the energy dissipation law of soil at different depths with the change of the ramming number, through theoretical derivation and analyze data such as the data of ramming settlement, vertical displacement, acceleration of rammer, continuous function time, impact of rammer and acceleration of layered soils.The analysis indicated that: the deformation of the dynamically compacted foundation soil constituted a dissipative structure, and the dissipative energy efficiency coefficient η was derived.With the increase of compaction cycles, the impact stress of the hammer on the foundation soil gradually increased, the overall compactness of the foundation soil gradually increased, and the energy dissipated for the overall reinforcement of the foundation soil gradually decreased.The greater the compaction energy, the longer the continuous action time of the hammer on the soil, and the more energy was dissipated for the overall reinforcement of the soil.With the increase of compaction cycles, the energy dissipated for the self-reinforcement of the upper soil layer of the foundation gradually decreased, then it remained stable, and finally gradually increased.The energy dissipated for the self-reinforcement of the middle soil layer gradually decreased, and then remained stable.The energy dissipated for the self-reinforcement of the lower soil layer gradually decreased, but compared with the upper and middle soil layers, the energy transmitted to the lower soil layer was smaller, the rate of increase in compactness was smaller, and the rate of reduction in energy dissipated for self-reinforcement was smaller, which had not reached a stable state.

         

      /

      返回文章
      返回