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Since the generation of prestressed concrete, the causes for losses of prestress have been always analyzed and studied and many achievements are made. However, as the losses of prestress result from many factors, it is very complicated to calculate various losses of prestress accurately. The formulas and methods used in the concrete codes of various countries for calculation of prestress losses vary according to their different purposes. This paper focuses on US code ACI 318-05, Eurocode EN 1992-1-1 and Chinese code GB 50010-2010 (the code for design of concrete structures), and carries out a comparative analysis in terms of losses of prestress for the three codes above.

A new type of composite structure, precast concrete tube column is proposed, and its axial compression performance and the seismic performance of beam-column joint are studied. Nine groups of precast concrete tube column models and three groups of common solid column contrast models with the same outer diameters (600,800,1000mm) were established by software ABAQUS, and a beam-column joint model for horizontal low cyclic loading was established combining with practical project. The results show that the ultimate bearing capacity of precast concrete tube column is higher than that of the common solid column with the same outer diameter by 5% to 20%, and it increases slightly as the thickness of tube increases. Displacement - load hysteresis curve of the beam-column joint is relatively full under cyclic load, and the slope of skeleton curve decreases slowly, which provides an important basis for engineering applications.

A new type of reinforced concrete (RC) structure termed concrete filled fabricated concrete tubular (CFFCT) was economically evaluated. Construction schedule time and construction cost of CFFCT and RC columns were analyzed both in case studies of building structure and bridge structure. A comparative analysis was done on two types of columns by studying on single column and present value of total construction cost. The results show that use of CFFCT shortens the construction schedule time and lowers the total construction cost. The investigation of the multistory building shows that using CFFCT results in an average of 2.31% savings on total project cost, an average of 28.67% savings on total column costs, 25.12% savings on total project time period, and 45.22% savings on columns construction time period. And the investigation of the bridge shows that using CFFCT results in an average of 3.27% savings on total project cost, an average of 46.87% savings on total column costs, 15.68% savings on total project time period, and 29.90% savings on columns construction time period.

The TiB2films were prepared on AISI 316L substrate by magnetron sputtering with various powers to investigate the influence of sputtering power on the microstructure and hardness of films. The crystalline structures and cross-sectional morphology of TiB2films were characterized by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM), respectively. The hardness was measured by nano-indentation. XRD patterns showed that the preferred orientation of TiB2films transferred from (100) to (001) with the increase of power. It can be observed that each film processed homogeneous by the cross-sectional images. The hardness of films varied from 21 to 32 GPa depending on the value of power. The enhancement of hardness may be attributed to the effect of the residual stress state and the microstructure of films. Furthermore, the effects of power on hardness of TiB2films were discussed in details.

In the present study, we apply microcontact printing (μCP) to create extracellular matrix (ECM) stripe patterns on polystyrene (PS) surfaces and then the effects of these patterns on osteoblast cell behaviors are investigated. The results demonstrate that osteoblast cells preferentially adhere and grow on the protein areas, leading to the deformed cell morphologies. Compared to the adherent cell on isotropic ECM coating, the deformed cells express more type I collagen and osteocalcin, indicating that the patterns can enhance protein expression of osteoblast cell by changing the cell morphologies. Therefore, it is possible to improve cell functions by carefully designing pattern shapes and sizes. We believe that the present results can contribute to development of the novel biomaterials and engineered tissues for bone repair, where the enhanced protein expression is needed.

Combined SHS with casting, in-situ Al2O3particle-reinforced copper matrix composite was fabricated. The effects of the load and Al2O3particle on the friction coefficient and wear volume were investigated. And the wear resistance of composite was compared with that of pure copper. The results show that with the increase of load, the coefficient of the copper increases, while it decreases slightly as to composite. The wear volume of the composite is always lower than that of copper. The highest relative wear ability is 4.5, which indicates a better wear resistance..

Conducting attapulgite/titania/polyaniline/ (ATP/TiO2/PANI) core-shell nanocomposites (CSNs) were synthesized via oxidative polymerization of aniline after the surface modification of the ATP carried with TiO2nanoparticles. The structure and morphology of the ATP/TiO2/PANI CSNs were characterized by X-ray diffraction, scanning electron microscopy, and fourier transform infrared. The thermal stability of the ATP/TiO2/PANI CSNs was also investigated by thermal analyzer. The results show that the ATP/TiO2/PANI CSNs display “capsule like” core-shell structure, of which ranging in diameter of about 80 nm and length of about 250 nm. In addition, the ATP/TiO2/PANI CSNs present a higher degree of crystallization and better thermal stability. We believe that the excellent core-shell structure and better thermal stability should be prone to improve their other properties and enlarge their application.

It was hard to predict crack and wrinkle which are the main failure modes when drawing for the shallow tapered parts. In this paper crack and wrinkle can be avoided effectively by using the software DYNAFORM in combination with orthogonal design of experiment method. The influence of normal anisotropy coefficient, friction coefficient, drawbead resistance and blank holding force on deep drawing shallow tapered surface was analyzed by numerical simulation. The results show that the minimum-wall-thickness was the main criterion for the drawing process but not the only criterion. Crack and wrinkle can be moderately eliminated finally after optimization of the parameters and following trim process in the drawing for shallow tapered surface.

The γ-Fe2O3/Al2O3core-shell nanocomposites (MCSs) were successfully synthesized by using heterogeneous nucleation method. The results show that a core-shell structures exit in γ-Fe2O3/Al2O3MCSs and that the size of γ-Fe2O3/Al2O3MCSs is in nanoscale. The saturated magnetization and coercivity of γ-Fe2O3/Al2O3MCSs decrease compared with that of γ-Fe2O3nanoparticles. However, the infrared absorbing ability of γ-Fe2O3/Al2O3MCSs is obvious enhanced and it is expected to become a new series of absorbing materials applied in military field.

The wettability between pure liquid titanium and calcia-stabilized zirconia was studied in argon atmosphere. The micrographic observations made on cross section perpendicular to the interface using SEM showed that interfacial reaction occurred. However, the contact angles were larger than 90°within experimental duration.

Internal air pressure and water pressure of the buckets foundation, acceleration and dragging force of the 4-bucket foundation platform were determined to analyze the influences of wave height on towing when 4-Bucket foundation platform is towing in conditions of a certain towing velocity, mooring point position and draught in different regular waves based on the model test. Comparing platform towing in following and head waves, the heave motion of the latter is more strenuous than that of the former; the stability and seakeeping of the former is better than those of the latter. Roll motion, pitch motion and heave motion appear aggravate phenomenon with the increase of wave height.

In this paper, the internal air pressure and bottom water pressure of the buckets, the acceleration of swaying, surging and heaving of platform were determined by the sensors fixed on the platform, as a naval bucket foundation platform for example. The motion rules of heave and sway of bucket foundations are studied with different drafts. The results of this test showed that the added mass coefficient of heave, roll and pitch are declined with the increase of the draft; the natural frequency of heave is constant with different drafts but the roll frequency and pitch frequency are consistent with the changes of the draft; the frequency of heave is larger than that of roll and pitch but the added mass coefficient of heave is lesser than that of roll and pitch.