以LS-DYNA探討衝擊波動態破壞機制

Analysis of Shock Wave Dynamic Fracture Mechnaism using LS-DYNA

劉瑜恆(Yu-Heng Liu)

指導教授 ： 丁原智

國立臺北科技大學/工程學院/資源工程研究所/碩士(2012年)

https://doi.org/10.6841/NTUT.2012.00579

摘要

過去由於電腦輔助工程分析(CAE, Computer-Aided Engineering)尚未發展至成熟階段，岩石爆破之探討只能根據爆破結果推移度與破碎度以及其他與岩體破壞相關之理論做研究，對於岩石受到衝擊波(Shock wave)衝擊荷載下所產生之破壞型態以及衝擊波於岩石內傳播之特性並未有完整之解析，近年來由於電腦輔助工程分析日趨成熟，岩石之破壞也可以運用此技術進行探討。有限元分析軟體LS-DYNA程序為世界上著名的通用顯示動力分析程序，能夠模擬任何複雜的結構計算問題，特別能針對各種二維及三維非線性結構如高速碰撞及爆炸衝擊等非線性動力問題進行求解，同時亦能求解傳熱、流體以及流固耦合問題。本研究即利用ANSYS11.0作為前處理器並以LS-DYNA進行求解來建立衝擊波動態模型，探討衝擊波在岩石間的傳播規律以及岩石受到爆破加載下所產生之動態破壞行為，本研究即以PETN高爆炸藥作為爆震源，針對不同藥量的炸藥在岩石中激起的爆炸衝擊波在岩石間傳播時的衰減情形進行計算，所得之模擬結果以Von Mises破壞準則以及損傷力學之基本理論進行分析，計算岩石受衝擊波破壞後之損傷程度並確立岩石的破壞型態，建立岩石損傷與衝擊波衰減規律之關係。

關鍵字

爆破 ； 衝擊波 ； 動態破壞

並列摘要

Since Computer-Aided Engineering hadn’t been developed very well in the past, rock blasting could only be explored on the basis of looseness and fragmentation as well as other rock failure related theories, there were not any complete analysis of the failure caused by the impact loading of shock wave on rocks and characteristics of shock wave propagation through rocks. In recent years because CAE is getting mature, the analysis of rock failure can be done by using this techniques.Finite element analysis procedure LS-DYNA is a general explicit dynamic analysis software which is very famous in the world and is able to solve non-linear dynamic problems of two dimensional and three dimensional structures such as high speed impact and blasting, besides, it is capable of dealing with the problems of heat, fluid and fluid-solid coupling as well.In this research, ANSYS 11.0 is used as preprocessor and LS-DYNA is used to solve in order to establish a shock wave dynamic model, exploring the propagation of shock wave through the rock and dynamic failure of rocks induced by blast loading. Different charges of PETN high explosive are used to calculate the attenuation of shock wave while propagating through the rock. Results of simulation are analyzed with Von Mises failure criterion and damage mechanism theory, calculating the extent of damages after being impacted by shock wave and exploring the failure pattern of rocks so as to correlate the rock damage with shock wave attenuation.

並列關鍵字

Blasting ； Shock Wave ； Dynamic Fracturing

參考文獻

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