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The structural characteristics of the tensioning device in the wire saw manufacturing equipment is introduced. Based on the characteristic of the strainer, the principle of variable universe fuzzy control is adopted to deal with the controlling objects. The design of two stage fuzzy controller and its parameters are discussed. The system simulation shows that the control scheme can make the tension within the stable range.

With the hybrid structure including outer steel grids and inner reinforced concrete core tubes (RCCT) as the background, the key problems involved in the performance-based structural design are analyzed and the table test is conducted. Anti-seismic and stability indicators are defined based on the structural characteristics; The research on seismic response is made through elastic-plastic time-history analysis and verified through the table test; The overall stability of the outer steel grids and the anti-collapse capability following the ineffectiveness of some key components are analyzed. Results show that the structure in which the outer steel grids are connected with internal steel frame and RCCT is practicable, and the said three systems can work together effectively; The time-history analysis shows that the structure is weak at the elevation of 5-15m but can still meet the expected anti-seismic target under rare earthquakes. The space steel structure features sound stability and high redundancy, which ensures the structure will not collapse even if several key components are damaged.

According to polypropylene fiber improving fly ash soil and based on a lot of dynamic-static tri-axial tests, the comparative analysis is made with dynamic-static strength parameters. Using the method of regressive analysis studied on the function relationship of the parameters. The influence law of the dynamic-static strength parameters after freeze-thaw cycles is analyzed. The influence of the dynamic-static tri-axial tests c after freeze-thaw cycles had great similarity. When the C and tended to be stable, the value decreased by 8%. The last three freeze-thaw cycles had great influence to and. When the and tended to be stable, the value decreased by 11%.

The main causes and influencing factors of artificial side soil slope slide of soil-cutting in seasonal frozen area are analyzed and put forward, and a mechanical theoretical model form is also put forward. Based on checking computation of artificial side slope saturated soil stability in melting period, it provides effective measures by adopting drainage to stabilize side slope instead of cutting it to keep soil-cutting side slope stable in the seasonal frozen area. Then the comprehensive stability technology of side slope by introducing geotextile as lower levels drainage and by adopting net geotextile lattice to stabilize soil and planting Malian grass.

Sliding and plowing are discriminated based on Hertz contact, and the grain number statistics model is established considering that grain size and abrasive protrusion height fit normal distribution. The analysis shows that less than 5% of grains are contacting with workpiece in the grinding arc, about 96% of contacting grains plow and about 4% cut. Sliding grains accounting for contacting grains is about 0.2%, which is almost negligible.

A special designed 2D accelerometer was successfully used in the design of the minitype 2D vector hydrophone. The theory, design and experiment test data of both the accelerometer and the vector hydrophone was presented in this paper. The accelerometer based on cantilever beam mode and used PZT tube to substitute the PZT plate which was traditional used, this substitution enhanced the mechanical strength of the accelerometer, which resulted to the high performance of the 2D vector hydrophone in its natural frequency and sensitivity. The outside electrode of the PZT tube was divided into four equivalent parts, and each opposite part was wiring connected into one accelerometer channel, thus the two orthotropic accelerometer channels was integrate into one 2D cantilever beam mode accelerometer. The minitype vector hydrophone was designed based on this compact 2D accelerometer, and it’s high performace makes it possible to be used in under water sonar transducer arrays.

This article, basing on the field test stress of an oil-storage tank in the site, investigated finite element modeling method for large oil storage tanks. To study the effects of contact conditions among the tank wall, bottom plate and the foundation, the soil of the foundation, and holing on the tank stress, six different finite element models were built by ANSYS finite element analysis software. The stresses in the tank were calculated under the gravity load and the water pressure. Results of the six models have been compared with the field test values. It was obtained for the stress distribution in the tank wall, bottom plate, and big horn weld and around the manhole from which the influence scope and extent to the tank was investigated. It shows that the calculated stresses have a good agreement with measurement. The plane model has enough precision for the tank stress analysis. The contact conditions and soil affect on the stress in the scope with 0.2H and 0.24H (the height of the tank), and holing affects the adjacent area with 2D (the diameter of the manhole).

The structural comfort of long-span floor structure which setup stadium is studied in this paper. The measured spectrum is used to simulate human movement loads. All possible loads are considered and key parameters about structural comfort of the long-span floor structure are analyzed, and then, the comfort of athletes in match and audiences on the stadium stand are analyzed. The results show the vertical acceleration and natural frequency of structure are decreased approximate linearly with increasing of the slab thickness; take one engineering project for example, according to the method proposed in this paper, the different structural comfort control index should be adopted in sports field and audience stand, respectively. Comprehensive and system design references of load simulation, pre-stressed structure dynamic analysis, comfort performance index and control standards are offered in this paper for long-span pre-stressed steel floor structure project that used for stadium.

Elastic tube bundles are universally used in heat transfer enhancement by flow-induced vibration in heat exchangers, and the study of the heat transfer performance is of importance. The structure of conical spiral tube bundle heat exchanger was introduced first, and the structure of pulsation flow generator was also introduced. The frequency of pulsation flow was discussed. Finally, in condition of same shell side diameter, the heat transfer and natural frequency of the conical spiral tube bundle were compared with the planar elastic tube bundle. The results show that the natural frequency of conical spiral tube bundle was smaller, the heat transfer performance of conical spiral tube bundle was better than the planar elastic tube bundle.

In this study, by the way of adding functional carbon nanotubes into the SBS modified rubber powder to obtain a new type of composite asphalt modifier. The new modified bitumen was prepared with the asphalt compound modifier. A lot of structure and road performance tests were carried out about the new modified asphalt and its mixture. The results demonstrated that after adding new type of carbon nanotube, the modified asphalt obtained a more stable internal structure; the performance index (softening point, penetration, and ductility) had better performance.

A wire-saw cut KDP crystal geometrical model was founded and a mathematical model was established to calculate the grit average cut depth, based on indentation fracture mechanics theory(IFMT). The relationship between the grit cut depth and wire saw process parameter was analyzed theoretically. The research results indicate that there exists an approximate monotone increasing non-linear correlation between grit average cut depth and the ratio i value of crystal feed speed and wire speed. By increasing the wire speed and crystal feed speed accordantly, the value of i can be maintained invariable, however, this way can simultaneously bring higher machined surface quality and machining efficiency.

The foundation of slope stability analysis is the data acquisition of the deformation. How to obtain the data detection point directly and efficiently is the access to achieve real-time predict method to slope stability. By introducing the Trimble GX 3D laser scanning data acquisition method, road slope detection method is put forward. According to the scanner system and working principle of the implementation steps, the slope detection and data processing procedures are developed and present references to the slope detection. With specific engineering application analysis, the feasibility of such acquisition is verified.