【摘要】 利用数值分析软件LS-DYNA3D程序,研究了在集中装药爆炸应力波的作用下,锚杆的动载响应及轴向应力分布规律.数值分析结果表明:通过对比拱顶同一位置的试验和数值模拟压应力时程曲线,说明数值模拟结果可信;通过分析拱顶、拱腰、拱脚和侧墙锚杆中间位置轴向应力时程曲线,发现拱顶既受压又受拉,并且受压较大,在施工时应尽量减少受压影响;根据拱顶、拱腰、拱脚和侧墙锚杆的轴向应力分布规律,得出受拉和受压都是先增加后减小,并且最大拉应力峰值点向锚端偏移,压应力峰值点靠近锚头;拱脚和侧墙锚杆压应力相对于拉应力几乎没有,此处的锚杆可能会由于拱部和边墙位移的不协调导致锚杆剪切破坏.更多还原

【Abstract】 Based on LS-DYNA3D software,we studied the dynamic response and axial stress distribution of rock bolts under the explosive stress waves produced by concentrated charging.The comparison between the pressure temporal curves and the test at the same place of vault shows that the numerical data are reliable.The axial stress temporal curves of rock bolts on vault,hance,spandrel,and rib indicate that the vault is affected by not only compressive stress but also by tensile stress,with the former being greater than the later.So the compressive effect should be decreased during construction.According to axial stress distribution along the bolts on vault,hance,spandrel,and rib,both the peak tension and the peak pressure increase first and then decrease,with the maximal peak tension being close to anchor end while the maximal peak pressure to the anchor head;the pressure of spandrel and rib is very small comparing to tension,where the underground opening may have shearing fault of rock bolts because of difference in displacement of arch and rib.更多还原