作为一种轻质高强材料,泡沫混凝土常用于滨海道路工程,结构承受着自重、波浪及交通载荷等多种静、动荷载作用。通过一系列静、动力三轴试验,研究了泡沫混凝土材料在静、动力加载条件下的变形与强度特性,并探讨动载历史对材料强度的影响。试验结果表明:泡沫混凝土在静压荷载作用下的变形发展呈现出先弹性后塑性的特点,其静力抗压强度约为1 040 kPa;当动力荷载幅值较小时,泡沫混凝土变形将逐渐趋于稳定,且动弹性模量随应变增长变化较小;而当循环荷载幅值较大时,材料将发生动力破坏。此外,随着先期动力荷载幅值的增大,泡沫混凝土的静力抗压强度先增大后减小。研究结果揭示了泡沫混凝土材料在静、动荷载作用下的工作机理,可对类似工程的应用提供参考。
Abstract
As a material of light weight and high strength, foam concrete is usually used in road engineering at coastal region subjected to different static and dynamic actions such as deadweight, wave force, and transportation loading. Static and dynamic triaxial tests were conducted to investigate the deformation and strength of foam concrete, and the influence of dynamic loading history on material strength was also discussed. Results indicate that under static loading, the deformation of foam concrete showed elastic tendency followed by plastic tendency subsequently, with the static compressive strength about 1 040 kPa; under small dynamic loading, deformation of foam concrete gradually became stable and dynamic elastic modulus changed slightly with the increase of strain; dynamic failure of foam concrete would be triggered if the dynamic loading amplitude was large. In addition, static compressive strength increased first and then decreased with the increasing amplitude of advanced dynamic loading. The results revealed the mechanical mechanism of foam concrete under static and dynamic loadings, which can be taken as reference for similar projects.
关键词
泡沫混凝土 /
三轴试验 /
力学特性 /
动载历史 /
荷载幅值
Key words
foam concrete /
triaxial test /
mechanical characteristics /
history of dynamic loading /
loading amplitude
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