Research On Expansion Test Of Montmorillonitic Soft Rock Changed By Organosilicon

Swelling rock have a volume change after a series of physical and chemical reactions with water which is rich in hydrophilic mineral composition.This hydrophilic mineral include montmorillonite,illite,kaolinite and so on.Because it expands after absorbing water and shrinks after water losing,they present the characteristics of multi-cracks and strong expansion and intensity decay.Because of its special nature,swelling rock bring huge economic losses to the country and people.Therefore,the research on the expansion mechanism of swell rock has an important engineering and practical significance.On the system analysis basis of relevant theory and research,Shandong Wali coal floor clay shale was taken as the research object which is rich in montmorillomite.After a series of macro-expansion tests on swell-shrink characteristics,this paper put forwards the method of change the physical characteristics of swelling rock via organosilicon and improve the water proofing property to inhibit its strong expansion of this rock.This paper has made some achievements summarized as follows:1?To know the structure characteristics of montmorillonite,illite and kaolinite crystals and summarizes and evaluate the advantages and disadvantages of kinds of swell-shrink theories of swelling rock and analyzes special geotechnical engineering properties and the causes of swelling rock.The theories include the lattice expansion theory,the electric double layer theory,percolation theory and microstructure theory.2?In the Conditions of optimum moisture content and maximum dry density determined by Heavy compaction test,the remodeling sample were obtained and using home-made expansion sleeve to study its swelling change rule in distilled water or solution of different concentrations and different valence cation and equivalent of chloride ion and in the wet and dry cycle conditions.3?Modified process of clay shale by organosilicon was analyzed,combined with the chemical bond theory.Through the surface contact angle test,organic silicon GJ657 was selected as the modifiers because its waterproof is superior to KH570.After modified,expansion test in disilled water is taken,and it showed that expansion ratio obviously reduce and show a good waterproof effect and the relationship between inflation rate and time was researched.4?By means of scanning electron microscopy,change of microscopic characteristics original rock samples are analyzed when immersed in distilled water,NaCl(1mol/L),CaCl2(1mol/L),AlCl3(1mol/L)and organosilicon GJ657.With the help of Fractal Theory and digital processing to rock samples SEM pictrues via Image pro-plus(IPP)software,the concave-convex appearance fractal dimension change was quantitatively studied.The quantitative research of rock samples include the surface area,pore size and pore volume through Liquid nitrogen isothermal adsorption test.