低速冲击作用下石灰岩动态损伤力学特性研究  

Mechanical characteristics of dynamic damage of limestone under low speed impact

作　　者：武宇 刘殿书[1] 张青成 刘志远 马建会 

机构地区：[1]中国矿业大学(北京),北京100083 [2]金诚信矿业管理股份有限公司,北京101500

出　　处：《河南理工大学学报（自然科学版）》2017年第6期139-144,共6页Journal of Henan Polytechnic University（Natural Science）

基　　金：中央高校基本科研业务费专项项目(2010QL05);教育部博士点基金资助项目(20100023110001)

摘　　要：为了研究石灰岩在低速冲击下的动态损伤力学特性,利用霍普金森压杆(SHPB)分别对波长为1.2,1.6 m的2种应力波作用下的5组石灰岩试样进行低速(3~7 m/s)冲击试验。试验结果发现,石灰岩表现出一定的应变率效应和波长效应。在低速冲击作用下,子弹速度与应变率呈指数关系;在低应变率下(<60 s^(-1)),损伤与应变率呈指数关系;应变率和峰值应力正相关,弹性模量与损伤线性相关。以此为依据,提出了适合于低速冲击的石灰岩损伤计算模型D=Ae^(αε)(βE+γ),利用试验数据拟合未知参数,并验证其准确性。In order to study the dynamic damage mechanics properties of limestone under low-velocity impact,the low speed（3 ~ 7 m/s） impact test is done on 5 groups of limestone samples respectively by using Split hopkinson pressure bar（ SHPB）. Two kinds of stress wavelength 1. 2 m and 1. 6 m are selected. It is found that the limestone shows certain strain rate and wavelength effect. Under the low speed impact,the bullet velocity and strain rate has exponential relations. At low strain rate（ 60 s^（-1））,damage is increased exponentially when the strain rate increases. The strain rate and peak stress shows positive correlation,elastic modulus and damage have the linear correlation. The suitable model D = Ae^（αε）（βE ＋ γ） is put forward for low speed impact of limestone damage calculation. The experimental data is used to fit unknown parameter and its accuracy si verified.

关 键 词：低速冲击 石灰岩动态损伤 霍普金森压杆 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]