Papers by Keyword: Test

Abstract: The similitude requirement of excited load was deduced to maintain the consistent vibration between scaled model and prototype structure, based on the modal theory of multi-DOFs systems. The similitude of load frequency was another demand to maintain the consistent vibration, with the similitude of structure size and load magnitude. The dynamic similitude problem of a liquid tank was studied by finite element method and test analysis respectively. The results show that the similitude of load frequency is the insurance for the consistency of prototype and scaled model structures vibration. In a case the magnitude error of displacement is 8% to 10%, and the displacement and acceleration have all changed distinctly without the similitude of load frequency. All the results indicate that the similitude of load frequency is the key factor to analyze the scaled model dynamics correctly.

Abstract: The young-old concrete can work together as a whole is the key issue of structural strengthening. Aiming at the technical selection problem appeared frequently in the bridge strengthening about the young-old concrete interface treatments between bonded rebar and grooving, 12 specimens were designed to compare with the shear performance and failure modes of the young-old concrete interface. The test results show that the failure characteristics of specimens which embedded steel bars are ductile, but the failure characteristics of specimens which slotted are brittle and the new concrete in slot position were cut off. And the young-old concrete interface shear strength of the specimens which embedded steel bars was distinctly stronger than that of the slotted specimens. So, the treatment of bonded rebar is proposed during the structural strengthening design. At the same time, the depth and distance of the bonded rebar should be well controlled.

Abstract: In order to understand the overall mechanical characteristics of a steel-concrete composite box girder bridge, static and dynamic tests were carried out. According to the results of tests and calculations, its bearing capacity and working performance were evaluated. The results show that the stress and deformation at control cross-section of the bridge meet design requirements under the static load, the vibration frequency and impact coefficient consistent with the theoretical calculation results under the dynamic load.

Abstract: An axial compression test was conducted to study the bearing capacity of the grouted connection with shear keys, and the curve of axial load vs displacement was got. Based on the experiment results, the crack distribution and damage zone of the cement grout is analyzed. With a proper design of the shear keys, grouting material and pipe structure, the grouted connection can achieve a good bearing capacity and ductility. A simplified finite element model was also set up to simulate the local behavior of the grouted connection. And, the numerical result is verified with the experiment phenomenon. This study can be a reference for the design of grouted connection.

Abstract: Because of inefficiency of many tests needed in GMI research, this paper put forward the sweep frequency measurement method to implement the measurement of GMI effect under multi frequency at the same time in a single test. Experiments proved that the GMI effect curves which are measured by the sweep measurement method are consistent with other method's results, and the sweep frequency measurement method can greatly reduce the time of GMI test and improving the efficiency of the test.

Abstract: Immerse cotton fabric into the TiO2 sol directly, which is produced by Titanate hydrolysis. Make cotton fabric and nano-TiO2 bind directly, so that the treated cotton fabric obtain a better decomposition of organic stains function. Combination fastness of fabric and TiO2 , self-cleaning function , regain , breaking strength , permeability , wrinkle recovery angle were tested.The results showed that: the fabric coated with nano-TiO2 has a self-cleaning function, good fastness, wrinkle recovery angle increases, moisture regain, tensile strength and permeability decrease slightly.

Abstract: Aiming at the difficulty in writing network security test programs, this paper designs and realizes a visualized network security test platform. It first defines a template for security test program, which encapsulates the commonly used network packet operations. Then it provides a visualized design interface, and saves the design results into description files. Finally it resolves the description files to form the security test program. This platform can simplify the design procedure, thus improve the efficiency of writing a network security test program.

Abstract: In the thesis, through the testing methods of textile anion, comparing with the flat rubbing negative-ion device and the overhanging vibrating negative-ion generating devicein, it introduces a closed automatic friction device and analyses its testing principles and results. Through the analysis to show the scientificalness and the normativing of this testing device.

Abstract: We developed a device for automatic closed friction and analyzed its test results in this paper, which showed the influence factors in the test methods of textile negative ion occurrence amounts. The textile negative ion occurrence amounts in different time stages were tested in this process; the analysis of its influence of temperature and humidity has certain reference significance for improving testing device for testing textile negative ion concentration, on the basis, functional textiles were also studied. Finally, we put forward the influence factors in the test methods of textile negative ion occurrence amounts.

Abstract: Mass concrete technology has been widely used in the construction field. In engineering construction, the quality and construction technology of mass concrete are directly related to the quality of the projects. Thus, before the construction of mass concrete, a series of experiments should be made, and also the key points of the construction technology should be strictly followed in the construction process. In this paper, by taking the application of mass concrete in stadium project as an example, the test before the construction of mass concrete and the technical application in the construction are analyzed.