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5 radial heat exchange wells were designed, and the different angle drilling, drilling pipe, and grouting backfill construction technology was studied. In addition, the heat transfer performance of the buried radial heat exchange wells was tested. The results show that, design of pipe equipment is feasible, construction is convenient, and the ratio of backfill material is reasonable; the heat transfer performance of 90 °buried tube is the best. The smaller the angle with the ground heat exchanger, the greater the heat exchange performance is affected by the surface temperature.

To improve the axial compression mechanical properties of the EPS particle-EPS board composite insulation wallboard, added fiber web at different levels of it, got the best arrangement to improve the performance of axial compression through the test.

The problem of form-finding for the suspended cable is actually the problem of determining all key points coordinates on main cable, which are by equilibrium relation on the horizontal force, main cable sagitta and lifting point force under the precondition of determining the endpoints boundary conditions of cable segment. According from the static equilibrium relationship of cable element, based on the analysis of its analytical solution process, in this paper, the cable elements are divided into two types in accordance withthe vertical distribution load along the arc length and along the string length , the corresponding shape curve of cable element is the parabola and the catenary, and with parabolic results as its initial value for the iteration of nonlinear solution, then cable element eventually converge for the catenary. And based on the exact coordinates results ,the calculation method of the length without stress is presented,and compiled corresponding computational procedures. By comparing the results of form-finding and the cable-length in non-stress according to program compiled and the results from the finite element software and the measured value of Aizhai suspension bridge, compared with the nonlinear finite element method,it confirmed the method requireing smaller dividing element density, the convergence speed is quicker and the results can ensure the precision.

In this paper, by establishing the finite element model to study the dynamic characteristics of rigid frame single-rib arch bridge. By respectively changing structural parameters of the span ratios, and the compressive stiffness of arch, and the bending stiffness of arch, and the bending stiffness of bridge girder, and the layout of boom to find out the regularity of the structure on lateral stiffness, and vertical stiffness, and torsional stiffness as well as dynamic properties, it come out the results of that lateral stiffness of the structure is weaker, and increasing the span ratios and the compressive strength of arch are conducive to the improvement of the overall stiffness, and improving the bending strength of arch and layout of boom are less effect on the overall stiffness and mode shape.

Magnetic separation is an emerging and promising technology in biological sample preparation. In this paper, a high-intensity and high-gradient magnetic separation system was developed to separate magnetic nanobeads from aqueous solution. This system mainly consisted of a magnetic separator, a micropump and an electronic timer. The magnetic separator was designed by placing two columns of permanent magnets in an aluminum holder. Two magnets in each column were laid out in repelling mode and a hole between the two columns was used to accommodate a 1.5 ml tube. Working with the electronic timer, the micropump was employed to remove waste solution at a certain rate after magnetic nanobeads captured onto the sides of the tube wall. The experiments for separation of magnetic nanobeads with diameters of 150 nm and 50 nm using the developed magnetic separation system were conducted to optimize the key parameters of the system including nanobeads concentration, separation time and flow rate. The separation efficiencies of magnetic nanobeads increased as the nanobeads concentration and the separation time increased, whereas decreased when the flow rate was increased. Experimental results proved that the proposed magnetic separation system was able to separate magnetic nanobeads (diameters of 150 nm and 50 nm) with separation efficiencies of 99% and 90% in 30 min and 150 min respectively.

：On the basis of preliminary exploration, complement exploration is executed to obtain excavation seepage analysis detail parameters. According to the three-dimension finite difference method and regulating calculation method, the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south and the influence of different depth rock-socketed on foundation seepage are discussed. With the experience in similar projects at home and abroad, the depth of diaphragm wall embedded in weak weathered rock is not less than 3 meters, grouting curtain wall consists of 10 meters, and the waterproof curtain outside the foundation is canceled from preliminary design. The stress, strain and water level are monitored during the excavation process, and the deformation of the supporting structure is within the control. The structure is under reasonable force and the sealing effect is obvious when the foundation is excavated. Construction practice shows that the excavation seepage analysis of anchorage circular foundation at Huangpu bridge south are consistent with engineering practice.

Based on plane strain theory, the formula for calculating the tensile stress on the interface between the steel tube and concrete under the axial pressure was derived, and the stress distribution coefficient K was analyzed. Practical formula for calculating the interfacial tensile stress of CFST members under low stress condition was fitted. Using the fitted formula the interfacial stress calculation process can be greatly simplified, and the results have enough assurance. This formula can be easily applied to CFST members’ interfacial stress calculation.

Based on tension-compression and bending equivalences, an equivalent single material plate is formed to substitute bridge deck of composite girder with steel fiber reinforced concrete (SFRC) and steel. Thickness and elastic modulus of the equivalent plate are then formulated. After three dimensional finite-element analyses of the bridge deck, in terms of shell element membrane effect and girder flexion-torsion theory, combined with compatibility of deformation, single material shell element stress is restored to stresses on SFRC plate and steel plate separately; shear force distribution on shear keys between SFRC and steel is analyzed.