| In recent years,with the development of hydraulic engineering industry,new hydraulic construction materials have been developed,which provides a reliable guarantee for the sustainable development of water conservancy projects in the future.Fly ash as admixture is widely used in concrete,which can not only reduce the mass concrete pouring process of the hydration heat,but also can improve the later strength of concrete,but the early strength of concrete is low.Silicon manganese slag as a kind of industrial waste,not only pollute the environment,but also the accumulation of a large number of occupation of land resources,the study found that manganese silicon slag in concrete,can improve the early strength of concrete,improve the internal structure of concrete,reduce crack.The study on the mixture of Mn Si slag and fly ash.At the same time,they also brought a lot of urgent problems which need to be solved,such as: when mixed with silicon manganese slag and fly ash,different dosage,different water-binder ratio,and different age in the concrete,the effects on the concrete strength as well as the mechanical properties of concrete are not clearly,etc.In this paper,an equal amount of fly ash were used to replace silicon manganese slag cement configuration into double mixing concrete.By adjusting the silicon manganese slag and water cement ratio,the cube compressive strength,splitting tensile strength,the axis of compressive strength with age of 28 d and the static mechanical properties,and compressive modulus of elasticity were studied.The best cement dosage were analysis with an equal amount of fly ash to replace silicon manganese slag.The main conclusions are as follows:(1)The cube compressive strength value which contain same manganese silicon slag and ash content was higher,and when 25% content reached the maximum compressive strength value.All the content of the early compressive strength were lower than the benchmark of compressive strength of concrete.,the lately strength growth faster.When the content was 25%,water cement ratio was 0.53,and the age was 7d,double mixing concrete compressive strength value was only about 88.8% of the benchmark concrete.When the age was 90 d,double mixing concrete compressive strength value is up to 107.3% of the base concrete.(2)When manganese silicon slag and ash at the same content,the optimal content of tensile splitting strength was about 25%.When the dosage was 20%,and the age was 28 d,the splitting tensile strength which 0.4 water cement ratio was 122% that which 0.53 water cement ratio.With the increase of dosage,splitting tensile strength increased first and then decreased.When water cement ratio was 0.4,the age was 90 d,and the dosage was 25%,the double mixing concrete splitting tensile strength is 111% of the benchmark concrete.But the dosage was 35%,the double mixing concrete splitting tensile strength is 93.5% of the benchmark concrete.(3)Double mixing concrete splitting tensile strength of the growth rate early is greater than the compressive strength.However,the compressive strength growth rate is greater than the splitting tensile strength of the growth rate lately.(4)The axial compressive strength first increased and then decreased with the increase of dosage when two water-binder ratio of double mixing concrete in 28 d age.When the manganese silicon slag and fly ash content is 25%,the axial compressive strength reached the maximum value,and then with the increase of dosage,the axial compressive strength value decreased.The influence on static compressive elastic modulus of concrete was similar to the influence on axial compressive strength.(5)The results can be obtained with the test results of double mixing static compressive elastic modulus of concrete that when the dosage were 20% and 25%,the static compressive elastic modulus was higher than the benchmark concrete.After that,with the increase of dosage,the elastic modulus value decreased,and the best dosage was about 25%. |
