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Drum-shaped stone tongue that there are 3 ~ 5 m thick wedge silt on the bottom formed in the junction of silt and the stone embankment by reclamation silt with mountain stone during the course of backfill. In the paper, on the basis of drills, superficia drilling holes, deep drilling holes and vibrating stop plank model, boundary stone embankment shape and soft soil layer depth were obtained, cross section of stone embankment and stone embankment boundary were revealed during the course of artificial fill, study the stone tongue shape, soft soil around stone tongue, silt characters on stone tongue bottom and reinforcement treatments were studied to obtain treatment method which can satisfy the engineering requirement and can save the engineering cost and provide mature construction technology and method for the similar subgrade treatment of sea reclamation engineering.

A new type of aluminum lithium alloy Al-Li-S-4 was investigated in this paper. Process of phosphoric acid anodization and method of making bonding joint sample was introduced. Micrographs of plate surface were study by scanning electron microscopy. The pattern of aluminum alloy was modified after anodization. Plates were bonded with FM94 film adhesive and cured at 121°Cin the special clamping fixture. Morphology of bonding sample cross-section interface was investigated after bonding and curing process.

The effects of process parameters on evolution of microstructures of 7055 aluminum alloy in creep age forming were studied and the microstrucures were analyzed using transmission electron microscopy (TEM). Some important results are obtained: with the increasing of ageing time, the size of platelet shaped (known as Guinier-Preston (G-P) zones) precipitates and spherical shaped η' precipitates increased, the number of platelet shaped precipitates increased too, while the number of η' precipitates decreased; the precipitates with almost the same size distributed continuously and uniformly along the grain boundary with quite narrow precipitate free zones (PFZs) at 5 hours of ageing time, when the ageing time increases to 8 hours, the distribution of the precipitates along the grain boundary becomes discontinuous and the PFZs gets wider, while with the further increasing of the ageing time, the precipitates distributed continuously again along the grain boundary and the PFZs become more wider. From comparison of stress-aged alloy to stress-free-aged alloy, it was found that after 20 hours ageing, the precipitates in the stress-aged alloy are slightly coarser and the PFZs are wider, the density of retained η' is lower with the development of η phase.