Applied Mechanics and Materials Vols. 94-96

Abstract: Based on the investigation of end plate and angle of semi-rigid connection in the steel frame of beam-column, an analysis of two connection type damage phenomenons, stiffness, bearing capacity and ductility, and then with the experimental results concluded above, the similarity and differences between the two semi-rigid connections can be extensively discussed. And with that， it can naturally be concluded that the end-plate connection is a good load capacity and ductility properties of semi-rigid connection type. These for, the conclusion can provide test basis for the ideal steel structure semi-rig seismic node design and application.

Abstract: This paper is to analyze the seismic response of the spatial structure supported by the column subjected to the near fault excitation. Three analysis models, such as fix base model, the SSI model without considering the radiation damping and the SSI model considering the radiation damping, are analyzed simultaneously subjected to the near fault excitation. The statistical analysis is carried out for the displacement at the mid-span, the axial force of the upper chord, the web and the bottom chord for the models.

Abstract: The contrast tests of 1 reinforced concrete(RC) beams and 4 RC beams strengthened with near-surface mounted carbon fiber reinforced polymer (FRP) strips have been carried out, under conditions of different damage degree of RC beams. It is mainly conducted to investigate the effects of FRP strips reinforcement of flexural strength. The experimental results indicate that significant strength on the ultimate load and rigidity of reinforced concrete beams can be realized by mounting FRP strips to the beams, and propagation of cracks were reduced obviously.

Abstract: On the basis of analyzing the special requirements for security for the high-level radioactive waste storage structure, the seismic design parameters of this engineering are determined. There is no criterion that determines the design ground motion parameters of underground engineering. Based on the thought of the severest design ground motion, the basic methods and principles to determine the design ground motion parameters of underground structure are put forward. The characteristics of high-level radioactive waste storage structure are analyzed, and the frequencies corresponding to the maxim modal participation factors are gain. Combined with the analysis of the site geological safety assessment report, through the initial search and optimization with the method of numerical simulation, the design ground motion parameters of the high-level radioactive waste storage structure on the specific site is determined. The method is easy to operate, which can also be applied in other important deep underground engineerings.

Abstract: In this paper, a mechanical model for bonded PZT actuator is presented. By analysis (analyzing) and researching principles of the bonded PZT drive combined with the second class of piezoelectric force - electric coupled constitutive equations based on continuum dynamics established along the length of PZT-driven model to the mechanical vibration. In (during) the modeling process, the impact of the bonding layer was mainly considered between the PZT and the structure.

Abstract: Analysis of wind-induced response of double-layer cylindrical reticulated shell by different methods of calculation . The results showed that the wind-induced response of the structure was increased and too safety by using existing load code calculation. Calculation of wind-induced response of double-layer cylindrical shell by using random vibration method, can only be considered first step mode, while the effect of high order mode could be ignored. The whole process of wind-induced response of the structure can be obtained by using combination of methods of harmony superposition and time-history analysis method, which can provide guidance for project design.

Abstract: This paper presents a method to simulate the mechanical behavior of magnetorheological fluid (MRF) subjected to magnetic field in the pre-yield region in ANSYS. The main idea is to devide an MRF element into two coincident elements, one of them has density and viscosity without shear modulus while another has shear modulus without density and viscosity. Taking a simply supported MRF sandwich beam as an example, good results and reasonable conclusion are obtained by comparing the results with the theoretical analysis and experimental study of Ref.[1]. The validity of finite element analysis is also investigated in this paper. At present, there is no exactly appropriate element type in ANSYS to model MRF, this kind of method called coincident elements method (CEM) will provide a new way to model the structures with MRF or MR dampers in ANSYS, and it also has reference roles for the future development of related elements in ANSYS.

Abstract: Test is mixed with a certain amount of fibers and recycled concrete aggregate made from fiber recycled concrete. Fiber is respectively used steel fiber or polypropylene fiber. Each fiber incorporation are five, recycled coarse aggregate replacement percentage is 50%.Contrast different fiber content made from fiber recycled concrete to normal recycled concrete and analyzes the compressive strength variation. To determine the rational content of fiber, provide a theoretical basis for practical engineering.

Abstract: In architectural design, the discrimination to the frame short column has two judging criteria: the judging criterion with the shear-span ratio λ«2 and the judging criterion with the height-width ratio H/h«4 . Whether they have consistency has been raised attention by the engineering personnel. Through the analysis of two judging criteria, We get that: the judging criterion λ«2 has extensive applicability; the judging criterion H/h«4 is the simple calculation method, and needs certain limitations. Meanwhile, by the analysis of the relationship between the shear-span ratio and the mechanical properties in frame short column, it is concluded that the shear-span ratio has the directly affect to the failure model, and the circular cross-section frame column has better mechanical properties.

Abstract: Concrete is a key support material of underground chamber, its stress state is important parameter that can characterize the stability of underground chambers. The changing rule of the electrical conductivity of C50 steel fiber concrete in relation to the changes of the current, voltage and pressure was studied experimentally. And resistivity-stress regression equations of the concrete was fitted with much high correlation coefficient. Research results show that: (1) within the framework of elastic deformation, the electrical conductivity of concrete increases with the strengthening pressure (i.e., the concrete resistivity decreases with increasing pressure); (2) there exists the good correlation between the resistivity and pressure of the concrete; (3) given the certain pressure, the conductivity of the concrete is to some extent unaffected by voltage and current.