大掺量粉煤灰混凝土应力－应变关系

摘要

Through the axial compression tests of the fly-ash concrete-blocks with three different mixture ratios during 90 and 365 days concrete age,the axial and transverse mechanical characteristics of stress-strain were determined and the mechanical property and energy costing of the test blocks were discussed.The stress and the strain of the test-blocks were calculated according to the national standard formulas and foreign representative formulas and were compared with the test results.The results show that the compressive strength,peak strain and elastic modulus of the test blocks increase with the quantity of fly-ash age increasing,while the hoop strain decreases.The research also indicates that the stress and the strain calculated by national standard formulas and Japanese formulas provide better evaluation both in the experiment result,and post-tress-strain relation of fly-ash concrete.%为研究大掺量粉煤灰混凝土后期力学关系，通过3种配合比的粉煤灰混凝土90 d及365 d的单向轴向加载试验，探讨其轴向和横向应力应变的力学特性以及耗能等。同时，采用我国规范公式以及国外具有代表性的公式进行应力应变计算并与试验结果相比较。研究表明：随着粉煤灰掺量和龄期的增加，混凝土抗压强度以及抗压强度对应的应变及弹性模量均能有效增大，但横向变形能力降低；中国规范公式和日本公式与试验数据吻合程度较高，尤其龄期为365 d时基本一致。因此，中国规范普通硅酸盐混凝土公式和日本常用普通硅酸盐混凝土公式能够较好的评价粉煤灰混凝土后期应力应变关系。