摘要
以岩土材料的疲劳损伤试验为基础,基于神经网络的系统分析方法和信号处理技术,对疲劳损伤过程进行在线监测,建立了损伤过程的数学模型,并提取了损伤参数。试验结果表明:在循环荷载的作用下,基于系统分析方法所定义的损伤参数对水泥土样与岩样的损伤发展状态十分敏感,能够有效地跟踪损伤的不同发展阶段。整个损伤过程被分为3个阶段,即疲劳裂纹萌生阶段、疲劳裂纹扩展阶段及疲劳裂纹高速扩展阶段。损伤参数跟踪显示,对于水泥掺入比与龄期均相同的水泥土试样,其疲劳寿命也会表现出较大的离散性;对组分存在差异的砂岩而言,即使疲劳寿命相同,所经历的损伤过程也不完全相同。
Based on the fatigue damage tests of rock-soil materials,a new mathematic model of the fatigue damage of rock-soil material is proposed by using system analysis method and signal process technique and the parameter of fatigue damage is defined by means of bulk tests. The results show that damage parameter defined is susceptible and can trace effectively damage process of the samples. The damage process is divided into crack pullulating,crack expanding and crack high-speed expanding stage. Moreover,the relation curve between damage parameter and cycle times shows that the fatigue age of cement samples which has the same adding cement ratio and age is different. The damage process of the sandstones which have different components is not completely similar,even though their fatigue age is the same.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2007年第S1期85-88,92,共5页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.40672176)资助
福建省自然科学基金项目(No.D0510009)资助
福州大学科技发展基金项目资助(No.2006-XY-11)。
关键词
岩土材料
疲劳损伤
系统分析
损伤监测
rock-soil material
fatigue damage
system analysis
damage monitoring
