红砂岩土在四点冲击荷载下的冲击试验分析

为研究四点冲击荷载作用下红砂岩土的加固作用效应,改装手动击实仪,拆卸冲击锤固定装置,使冲击锤落距可以自主选择,对红砂岩土进行击实试验。根据试验得出的四点冲击荷载下4个冲击点所围成的正方形土柱的密度和抗剪强度的变化趋势,以及3个土层平均密度的变化,探索红砂岩土中能量的传递规律。结果表明:密度沿深度先变大后变小,距离夯点越近密度越大;抗剪强度随落距增长而增长,使其增长的主要原因是黏聚力;总冲击能持续增大到一定程度时,土体在上、下层面的平均密度的值存在一个转折点,3层土体的平均密度的变化最终将趋于一条直线。

Study on indoor impact test of red sandstone soil under four-point tamping

To study the reinforcement effect on red sandstone under four-point tamping, the refitted manual compaction text equipment without the hammer fixing device was used to carry out compaction in which the drop distance of the impact hammer can be freely selected.According to the the changes of the density and the shear strength in a square soil under four-point tamping,and the changes of the average density in three layers soil, the impact energy transfer laws in the soil were explored. The results show that along the depth the density firstly increases and then decreases, and that the closer to the tamping point the greater the density is. The shear strength increases as the drop distance increases,and the main factor is the cohesive force. During the increase of total energy, the average density of the upper soil and the lower soil has a turning point, and eventually the change curve of the average density in this three layers soil will be a straight line.These results provide reference to studying the reinforcement effect on red sandstone soil in impact tests.