Study On Engineering Mechanics Test Of Cotton Straw-Desulfurization Gypsum-Based Curing Pile

Cotton straw is the main byproduct of the cultivation of cotton,so its effective treatm ent is a question which has the matter with environmental protection and resource utili zation.This paper set up on solving this problem.In case of the good physical and mec hanical properties of cotton straw,the cotton straw is analogous to the "reinforced" rein forcement in reinforced concrete which was used in later reinforcement.That provides an effective way to consume the cotton straw.What's more,desulphurized gypsum as an important by-product of flue gas desulfurization in coal-fired power plants,the recy cling of it is of interest to many scholars.However,most of these studies require calcin ating gypsum to form construction gypsum to stimulate activity.This papper uses anot her way which add slag,soil,stimulants in the original desulfurization gypsum to form a gypsum-based cementitious material to be used as a solid foundation curing agent.T he solidified pile can be combined with soil to form a pile foundation to enhance the str ength of the blown fill.Before the experiment,the range and the experimental conditions of the solidified pil e were determined on the basis of predecessors' research by single factor experiment an d contrast experiment.Then the effects of five factors,such as the density of cotton str aw,the mass ratio of slag and gypsum,the amount of water and the amount of activato r,which effect the physicl and mechanical properties of cotton straw-desulphurized gy psum-based solidified piles were studied by orthogonal experiment.The properties mai nly include density,compressive strength,flexural strength,elastic modulus,softening coefficient,water absorption and so on.In these piles,the maximum compressive stren gth is 14.69 MPa,the maximum flexural strength is 1.24 MPa and the softening coeffic ient is 0.97,which indicates that the cotton straw-desulphurization gypsum base materi al has excellent application prospect.Under the experimental conditions of the project site,the performance under the infl uence of the factors was analyzed,and the optimal ratio of the solidified piles used in p ractice was determined as A2B3C3D3E4,that is 30%soil,28%desulfurized gypsum a nd 42%slag with a water to solid ratio of 0.25,1.5%NaOH and 15 g/cm3 cotton stra w.In this ratio,the solidified pile not only has the size of the regular,moderate density,less back to the amount of frost,but also ensure a high resistance to bending,anti-defo rmation,anti-softening performance under the conditions of adequate compressive stre ngth.Combining with further research of the curing mechanism of pile material,which ex plains the combination of curing process of hardening mixture and connection between the net pulp and straw.This provides a reference for researches of the reclaimed soil o f straw,desulfurization gypsum reinforced with cement materials base net pulp.