Red mud-steel slag composite geopolymer cementing material for soft base solidification

Abstract

The invention discloses a red mud-steel slag composite geopolymer cementing material for soft base solidification. The cementing material is adopted for soft base solidification and soil improvement.The main body of the cementing material consists of red mud, steel slag, cement, metakaolin and an early strength water reduction agent. Active aluminate and silicate components of the cementing material are provided from the red mud and the metakaolin, minerals in the steel slag, the metakaolin and the red mud are activated by the alkali properties of the red mud self and a small amount of the cement to carry out a hydration reaction, then cementing substances can be generated, and the red mud-steel slag composite geopolymer cementing material is relatively high in strength and good in property. The mass ratio of the red mud to the steel slag to the cement to the metakaolin is (42-50):(35-41):(4.5-10.5):(4-10):(1-2). When the cementing material is applied to soft soil solidification, theutilization rates of the two wastes, namely the red mud and the steel slag, can be increased, application of the cement in soft base solidification can be also reduced, the soft base solidification cost can be reduced, and good environment benefits can be made.

Description

technical field [0001] The invention relates to a red mud-steel slag composite geopolymer cementitious material used for soft foundation reinforcement, and belongs to the technical field of roadbed treatment in civil engineering and transportation engineering. Background technique [0002] Red mud is an industrial solid waste obtained from smelting alumina from bauxite. my country is the fourth largest producer of alumina in the world, and the annual production of red mud is as high as 30 million tons. However, due to the characteristics of high alkalinity and low hydration activity of red mud, it is difficult to use it, and the comprehensive utilization rate is only 15%. Steel slag is an industrial solid waste produced by smelting iron and steel. Our country produces about 100-150 million tons of steel slag every year. Developed countries have a complete steel slag recycling system, while the comprehensive utilization rate of steel slag in my country is only 50%. The stac...

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Problems solved by technology

Gu Mingyuan (publication number CN104988322A) proposed to mix and roast red mud, steel slag and reducing agent and separate the reaction products to obtain iron products and tailings. The re-smelting efficiency of the waste is not high, and tailings are still produced, so the problem of tailings stacking needs to be solved; Liu Liqiang (public number CN103304141A) proposed to use steel slag, red mud, and river sand for heat treatment to prepare glass ceramics, although this The method realizes the comprehensive utilization of two kinds of industrial wastes at the same time, and does not generate new wastes, but this method requires a large amount of energy to achieve recycling, and is not suitable for large-scale application; Deng Yongfeng (public number CN106316171A) proposed to use cement Stimulate the activity of steel slag, supplement the content of active aluminum in the system through metakaolin, and add a composite water reducer to improve the early strength, and control the dosage of each component through the ratio of silicon SM, aluminum ratio IM, and lime saturation coefficient KH, although this method The cost of the obtained steel slag-based cement is only half of that of ordinary Portland cement. However, this method still needs to consume a large amount of cement to provide an alkaline environment to stimulate the activity of steel slag; , Industrial by-product alkali residue, tetrahydrophthalic anhydride ester and ethylene glycol bis-trimellitic anhydride ester are mixed with red mud to form a curing agent. Although this formula can obtain working strength in a short time, the organic raw materials used Is a contact allergen material, inconvenient to apply, and may have adverse effects on the environment

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