EVA和钢纤维改性混凝土力学特性研究

Study on Mechanical Properties of EVA and Steel Fiber Modified Concrete

通过对不同掺量的乙烯-醋酸乙烯共聚物(EVA)和钢纤维对混凝土的力学性能和耐久性能的影响规律研究,得到了一种用于井巷修补及巷旁充填的新型聚合物改性混凝土,并确定了各组分之间最佳配比。结果表明:EVA会降低混凝土的抗压强度,当掺量达到15%时,对混凝土的塑性变形能力和延性会有较好的提升;钢纤维会提高混凝土的强度和延性,在体积掺量为1.5%时,效果更明显;在C组中,钢纤维体积掺量为1.5%时,各方面的力学性能相比于体积掺量为1%时提高的较少。C3试验效果最佳,使混凝土塑性变性能力和延性得到显著提升,混凝土的劈裂抗拉强度增加了6.1%,抗折强度增加了29%,跨中挠度增加了420%,弹性模量从3.25 GPa降到了1.12 GPa,极大地提高了混凝土的力学性能和耐久性能。

Through the study on the influences of different dosages of ethylene-vinyl acetate copolymer(EVA)and steel fiber on the mechanical properties and durability of concrete,a new polymer modified concrete for roadway repair and roadside filling was obtained,and the optimal ratio of each component was determined.The results are concluded as follows.EVA will reduce the compressive strength of concrete,and when the content of EVA reaches 15%,the plastic deformation capacity and ductility of concrete will be improved.Steel fiber can improve the strength and ductility of concrete,and the effect is more obvious when the volume content is 1.5%.In group C,when the volume content of steel fiber was 1.5%,the mechanical properties were less improved than that when the volume content was 1%.The C3 test has the best effect,which significantly improves the plasticity and ductility of concrete.And the splitting tensile strength of concrete is increased by 6.1%,the flexural strength by 29%,the mid span deflection by 420%,and the elastic modulus from 3.25 GPa to 1.12 GPa.The C3 test greatly improves the mechanical properties and durability of concrete.