橡胶粉掺量和粒径对混凝土物理力学性能的影响研究

Research on Influence of Rubber Powder Content and Particle Size on the Physical and Mechanical Properties of Concrete

通过净浆、砂浆和混凝土3个层面,研究了橡胶混凝土的物理力学性能。对不同橡胶粉掺量(0%、1%、2%、3%、4%、5%)和粒径(30目、40目和60目)下的物理力学指标进行了对比分析。结果表明:随着橡胶粉掺量的增加,水泥的凝结时间逐渐增大,砂浆的表观密度逐渐减小,而混凝土的坍落度变化很小;添加5%的30目的橡胶粉使净浆、砂浆和混凝土的抗压强度分别下降42.8%、22.9%和35.7%,抗折强度分别下降9.8%、8.2%和10.3%,砂浆和混凝土的折压比分别增大31.7%和8.9%。表明橡胶粉的加入虽然降低了强度,却提高了韧性。当掺量相同时,橡胶粉粒径越小,水泥凝结时间越长,砂浆的表观密度和混凝土的坍落度越小;净浆、砂浆和混凝土的强度都随橡胶粉粒径减小而减小,粒径越小,砂浆的折压比越小,而混凝土的折压比随粒径的变化规律不明显。

The physical and mechanical properties of the rubberized concrete were investigated based on the test of paste、mortar and concrete specimens. Analyzed the physical and mechanical indexes on different rubber powder content（ 0%,1%,2%,3%,4% and 5%） and size（ 30 mesh,40 mesh and 60mesh）. The results indicated that： with the increase of rubber powder content,the setting time of cement is increased gradually,the apparent density of mortar decreases,while the concrete slump constant small changes; when added 5% of 30 mesh rubber powder,the compressive strength of the cement paste、mortar and concrete decreased 42. 8% 、22. 9% and 35. 7% respectively,the flexural strength decreased respectively 9. 8% 、8. 2% and 10. 3%,while the fracture pressure ratio of mortar and concrete increased respectively by 31. 7% and 8. 9%. Show that adding rubber powder can reduce the strength,but increased the toughness. When the content of the same,the smaller the particle size of rubber powder,the longer the setting time of cement,the smaller the apparent density of mortar and concrete slump; the strength of paste、mortar and concrete are decreasing with the decrease of particle size of rubber,the smaller the particle size,the the smaller the fracture pressure ratio of mortar,while the variation of fracture pressure ratio of concrete with particle size is not obvious.