Research On Development And Reaction Mechanism Of A New Type Of Soft Soil Hardener

Aiming at the soft soil in Jiangmen city,Guangdong Province, this paper addressed to the creation of a new type soft soil hardener which using two sorts of industry waste residue ,such as the UFA, desulphogypsum (viz.GT mixed material) which produced from thermal power plants ,through plenty of indoor experiments. We achieve some physical and chemical properties of strengthened soil ,the factors affected the strength of the strengthened soil were analysed , the different factors affected the properties of the strengthened soil were researched .Moreover ,I study and probe into carefully the reaction mechanism of the strengthened soil from microcosmic view of point .The results were proved:(l) For soft clay of highly water content and ratio of small opening ,the feasibility of the hardener which add the GT mixed material is fairly well. The unconfined compressive strength with right proportioning by means of experiments not only can reach and exceed indeed the corresponding 28d period strength of cement strengthened soil ,and the progress of later strength of strengthened soil is fairly good ;(2) The strengthen soil would not engender the additional load and biggish settlement to the un strengthen soil for the density of gravity of strengthened soil is closed to the saturated density of gravity of natural soil ;(3) The main factors which affects of strengthened soil is the quantity ratio of cement, the quantity ratio of GT mixed material (especially the quantity ratio of gypsum), time and the rate of water content ;(4) We discover the reaction mechanism to enhance the strength of strengthened soil of GT mixed material through the test of scan electron microscope . Except that the HFA is participated in reacting ,the mainly cause is gypsum and aluminium sour calcium of cement react and produce the Ettringite . Because the volume of strengthened soil is expanded and pack the holes , therefore, it can solidify the strengthened soil structure , the hole amount is reduced, its needle of crystallization in post form cross each other and form the unique space reticular formation together with CSH ,so form fairly fine support structure among hole , make hole to be thinning , then proceed to the next step to improve strength of strengthen soil, and will not produce the unstable problem .