| Human beings have gained one after another brilliant achievements, but at the same time they also bring the earth and themselves into one after another hidden troubles. Today, human beings face lots of unprecedented challenges, such as explosion of the population, acute reduction of the soil area, exhaustion of the resource and energy and serious pollution of the environment. For the living of human beings and the benefits of offspring, we should consider moving our feet to the sky, the desert, the grassland, the polar region and even the ocean and the outer space. So human beings begin to dream of constructing the Sky City, the Mirage, the Ocean Station, the Space Elevator, the Outer Space Bastion, and etc.To get out of the difficult dilemma of living and development, meet the needs of urbanization and infrastructure construction, and realize the dream of human beings , an irreversible trend is to develop, to research and to utilize new materials, first of which are structural materials.We can foresee that new structural materials should fulfill the requirements of ultra great height or ultra large span (even over 1000 meters). Based on this and the viewpoints of professor PU Xincheng, the author defines the Kilometer Compressive Material (KCM), gives the criterion of the properties and choosing requirements, brings forward the preparation method of the KCM, and prospects the future of this new structural material.After investigating the structural materials largely used hitherto and the development trend of two leading structural materials, namely, steel and concrete, the author drew the conclusion that the steel tubular confined super high strength concrete was one of the best candidates for KCM. In the last chapter of the thesis, through case compute, the author gained the calculated loading, the nominal strength, the strength to weight ratio, the weight of column, and the cost of super high strength steel confined super high strength concrete column. By comparing these properties with 5 types of shaped steel columns, the author concluded that the super high strength steel confined ultra high strength concrete was the best choice for KCM.Super high strength concrete (SHHC) has a lot of advantages over ordinary concrete, such as high strength and elastic modulus, and good durability. Howerver, its large fragility makes the ordinary bar arrangement unsuitable and utilization of steeltube confined concrete is the best replacement for this. Besides, to make the super high strength concrete completely meet the needs of constrution in situ, workability and shrinkage, expecially large autogenous shrinkage, should be solved and necessary basic mechanical properties should be provided as well. After settling problems of super high strengh concrete itself and applying it to the steel tube confined concrete structure, the preparing techniques, mechanical behavior, stress-strain response, and coordination between SHHC and steel tube should be known first. Therefore, five parts of work are included in the reasearch:1) Research and develop super high strength concrete with compressive strength about 100~160MPa, and analyze its microstructure.2) Study the shrinkage (especially autogenious shrinkage ) of SHHC, and probe into the efficient way of reducing it.3) Measure the mechanical properties of SHHC, including cubic compressive strength, splitting tensile strength, flexural strength, uniaxial compressive strength, uniaxial stress-strain response curve; analyze the characteristics of stress-strain response curve; and simulate and build the stress-strain response relationship.4) Prepare steel tube confined SHHC member, measure the limit load, ultimate deformation, and load-displacement relationship.5) Analyze the load-displacement relationship curve of steel tube confined SHHC, build stress-strain model, and discuss the coordinate work mechanism.After experiment work and numerical analyses, the writer achieved the results as follows:1) With backscattered scanning electron microscope (BSE), the author qualitativel...
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