路基冲击压实效果分析

冲击压实的被冲压体响应是目前尚未解决的理论问题。基于应变能与冲击能分布密度相等的基本原理,假定:冲压n遍后的被冲压体为一维问题,冲压影响深度h0处应变为零,应变与弹性模量线性变化,建立了单次冲击能量、遍数等与土体压实度的关系,在施工参数与效果间建立了关联。结果表明,以相同的设备参数进行施工时,冲压影响深度随冲压遍数的增加而减小;前几遍冲压能影响较大深度,而后续冲击的影响逐步局限于上部土体。通过某砂性土工程实例,分析预测得知,单层80 cm冲压35遍仍达不到规定的压实度要求,因此,实体工程中需采用分层压实的措施。所以,本研究可用于对冲压效果的预测,也可在冲压目标明确的情况下预估需要进行冲压的遍数。

Compaction Effect Analysis of Roadbed Using Impact Compacter

The condition of soil after compacted with impacting model is still a theoretical problem.Based on the principle of equal distribution densities of strain energy and impact energy,assuming that impacted soil is a one dimension problem after n times compaction,the strain at impact influent depth h0 is zero,and elastic modulus changes linearly with strain within this height,the relationship of single impact energy,compaction times and degree was established,and the relationship of construction parameters and effectiveness was established too.The result shows that,when constructing with the same conditions, the influence depth decrease with the addition of impacting times;the first several times impact affect a thicker layer,and the subsequent impact mainly affect the upper part.An example of test road built by noncoherent soil shows that 35 times of compaction cannot meet the compact degree at the depth of 80 centimeters,so it should be divided into two layers for compaction,and so do in the practical construction project.