【摘要】 提出利用空心铝合金透射杆测量混凝土层裂强度的新实验技术。子弹撞击Hopkinson杆在细长混凝土杆件产生压缩加载波,此压缩波传播至试件和空心铝管接触面时反射成拉伸波使试件产生层裂破坏。通过测量空心铝管的应变波形可以测量混凝土层裂强度。通过空心铝管上不同位置应变波形以及试件与铝管接触面压力波形的对比,说明此方案能解决先前实验技术中为满足波阻抗条件采用粘弹性材料杆而引起的波形的弥散和衰减问题,实验方法更为简单,实验结果也更为可信。更多还原

【Abstract】 A novel experimental technique to determine the spalling strength of concrete with hollow aluminum alloy pipe as transmitted bar is proposed. The compressive loading pulse introduced by the impact of projectile travels along the slender concrete bar and part of it is reflected back into the concrete bar as a tensile one when it arrivals at the concretetransmitted bar interface. The concrete specimen may be spall fractured by the reflected tensile wave. The spalling strength of concrete may be measured by means of the strain wave in the hollow transmitted pipe. The comparison between the strain wave profiles at different locations of the hollow aluminum alloy pipe and pressure pulse of the concretetransmitted bar interface indicates that this experimental technique can solve the stress wave dispersion and dissipation due to the visco-elasticity of transmitted bar used in the past experiment methods to meet the mechanical impedance condition. This method is simpler and more convenient for the determination of spalling strength of concrete and can yield.更多还原