Applied Mechanics and Materials Vols. 584-586

Abstract: Steel claddings such as a long spanned roof have been damaged by metal fatigue affected by wind load or thermal load. To reduce damage of steel claddings, it is necessary for design and construction to consider metal fatigue influence. This paper shows a basic data for steel claddings to evaluate fatigue damage caused by cyclic thermal expansion exposed to solar radiation. Specimens are fabricated which specification are steel sidings and steel sandwich panels, and surface temperatures of specimens are measured throughout the year. Then, amplitude temperatures and their cyclic numbers are evaluated.

Abstract: The purpose of this paper is aimed at according to the "highway reinforced concrete and prestressed concrete bridge and culvert design specifications (JTG D62-2004) and (JTJ 023-85) design of jacking construction of continuous girder bridge for reliability analysis. By establishing a finite element model of construction stage and into a bridge stage respectively the reliability index of the typical cross section is analyzed. Aiming at construction stage, by choosing typical cross section of reliability analysis, draw a cross section of reliability index with the change of construction stage. Calculation results show that, according to JTG D62-2004 specification of reliability index calculation results than based on results of calculating the JTJ 023-85 specification. In this paper, the analysis results can provide reference for pushing the construction of the continuous girder bridge design.

Abstract: A vibration signal acquisition system was designed based virtual instrument technology. The process and principle design of structure vibration signal acquisition system based on LabVIEW software and CompactRIO hardware were discussed in detail. Finally, system test was conducted by a three story steel frame structure. And the test results were compared with traditional instruments system. The experiment showed that the data acquisition system of structure vibration signal which based on CompactRIO is precise and reliable in measurement results, and can realize multi channel synchronous data acquisition, storage, and support the real-time online data filtering and spectrum analysis and so on.Compared with the traditional platforms, the system proposed in the paper has short development cycle, low cost, user-defined functions, rugged, portable and other advantages. It can be widely used in complex and special building environment, so it will have a broad application prospect in the field of SHM.

Abstract: Using the Two-way composite loading experimental device, the bearing performance of post-grouting drilled shaft under lateral and axial load is studied by full-scale field test. The result of this research reveals that the lateral critical load Hcr and lateral ultimate load Hu are improved when the axial load is applied to post-grouting drilled shaft, the settlement of post-grouting drilled shaft and not grouting drilled shaft increase while the axial load is close to ultimate load, because the settlement of a foundation pile has a relationship with the size of axial load on the top of pile in the damage process of drilled shaft under lateral load, as well as the variation of vertical settlement of normal drilled shaft is more than that of post-grouting drilled shaft, since the non-grouting drilled shaft is more sensitive to the lateral load than the post-grouting drilled shaft.

Abstract: A new type of frictional pendulum TMD is designed. The wind-induced vibration of Henan Art Center Symbolic Tower with and without TMD is analyzed. The structural design of frictional pendulum TMD is presented in detail. The equivalent analysis model is established. The 3D analysis of the symbolic tower is established using SAP2000. The non-linear LINK unit in SAP2000 is used to simulate frictional pendulum TMD. Then, the non-linear analysis of wind control effectiveness of frictional pendulum TMD is carried out. The analysis results demonstrate that optimal frictional force can be chosen according to design wind loads and the control effectiveness can be over 30% with the chosen frictional force under 0.3 to 2 times of the designed wind loads.

Abstract: By utilizing the transverse joint opening and closing iteration technique and the finite element method based on the discontinuous deformation theory for manifolds, and with the help of measured data in situ of temperature, stress and displacement and so on during the construction period, the dynamic tracing feedback simulation/analysis was carried out to the temperature field and the stress field. On this basis, a series of effective safety control measures and methods were systematically put forward, which are beneficial to safety construction in the high temperature season and winter, improvement of the safety coefficient for restrained zones, lowering the cracking risk of low gradation concrete in portholes, ensuring the transverse joints aperture and groutability as well as effective control of the cantilever height and so on; and good effects have been obtained in the engineering practice and the important guarantee may be provided for the overall safety of Xiluodu Super-high arch dam.

Abstract: With the increased competition of modern enterprises, improving quality is emerging as the key to enterprise’s survival. In offshore oil field, quality is related to people's life. Welding process has been pay special attention as the most important thing in ocean oil construction. Based on the ocean oil construction, take quality management during construction as the research object, establish a quality management system, especially set up fine welding quality fine control processes, take Microsoft sharepoint, office as the tool, in order to realize the quality management in construction process.

Abstract: Through general examination, special detection and bearing capacity calculation and analysis, we make a comprehensive evaluation on the bearing capacity and work state, which provides information and data detailed reference to repair.

Abstract: Through the honeycomb damage that is appear in unballasted track will affect the safe operation of high-speed train, accurate detection of honeycomb damage is very important. Impact-echo method is a non-destructive testing method. Based on the principle of impact echo, author using the finite element software ANSYS LS-DYNA3D to simulate the impact-echo, testing and verifying the feasibility and accuracy of impact-echo method in discerning unballasted track damage. By analyzing the calculated result of honeycomb damage in slab track and double-block ballastless track, it is shows that: according to back calculate the depth of damage base on the peak value in acceleration spectrum graph, the honeycomb damage in different depth can be accurate located.

Abstract: In practical, the drainage cushion layer (such as sand layer) has certain permeability. It means the permeability of the drainage cushion layer is neither a infinitesimal or infinity. This condition is named as the semi-permeable boundary. In the existing consolidation analysis, this condition is simplified as the ideal drainage boundaries. And the difference between the computational results and measured data is big. Based on the existing research results, the consolidation modal of sand-drained layer ground with the impeded boundaries under hierarchical loadings is derived. The compared results show the modal is reasonable.