哑铃型钢纤维粉煤灰混凝土基本力学性能及抗弯韧性

Basics Performance Characteristics and Flexural Toughness of Dumb-Bell Steel Fiber Reinforced Fly Ash Concretes

为了研究哑铃型钢纤维对混凝土力学性能的效用 ,试验研究了新拌纤维混凝土的坍落度和密度 ,测定了纤维混凝土的抗压强度、弹性模量、抗劈裂强度 ;基于美国 ASTM及日本 JCI方法 ,用四点弯曲梁测得了抗弯初裂强度、抗弯拉强度和抗弯韧性等。试验证明 :哑铃型纤维能够均匀地分散在混凝土中 ,纤维无结团现象 ;该纤维对混凝土具有良好的增强和增韧双重效应 ,对抗弯初裂强度。

Fresh properties of dumb bell steel fiber reinforced concrete, such as slump and unit weight, are studied. For the hardened concrete,compressive strength, elastic modulus, split strength,first crack strength and modulus of rupture are measured.Load deflection curves are plotted from the data obtained in the modulus of rupture test in order to determine the toughness indexes by the ASTM method,and the flexural toughness factor and equivalent flexural strength by the Japanese Standard method using four point bending beam. The test results show that the dumb bell fiber may not be balled and can be uniformly distributed in concrete during mixing. This kind of dumb bell steel fiber has dual efforts of increasing strength and increasing toughness on concrete.There is a significant increase in flexure strength,spilt strength and toughness indexes with the addition of steel fibers. \ \