Papers by Keyword: Model Test

Abstract: The present case-study was aimed at evaluating and comparing the frictional properties (friction and wear) of alternative concepts for a shaft-bushing component in comparison to the actually used benchmark system. Through the use of a specially designed shaft-bushing tribology labor-sized test setup in combination with a high-precision modular tribometer, the overall performance of alternative concepts were evaluated and compared. Benchmark shafts consisted of nitro-carburized and oxidized bearing steel and benchmark bushings were made of sintered steel. The investigated alternative concepts consisted of shafts with a different thermal pre-treatment against benchmark bushings; benchmark shafts against surface modified bushings; and lubricated benchmark bushings (instead of lubricated shafts) with two different lubrication times before testing. For each concept under study, 3 performance tests were performed in order to assess the reproducibility of the results obtained. The most promising alternative component concepts identified through this labor-sized model screen test were then field tested by IMS Gear and the obtained results were in accordance with the labor test results.

Abstract: The nitration reaction is one kind of important reaction in many synthetic chemical reactions. The reaction with a high temperature releases a lot of heat and is easy to get out of control. The energetic materials is the main ingredients of the reaction mixture in late of nitrification of energy-containing materials, the accident about burn or rapid energy release will happen once the reaction is out of hand. There are so many thermal safety studies of energy materials, but the thermal safety research about energy material nitrification production line is not reported. Using the designed multi-scale energy material test, the thermal stability of DINA (N-Nitro-dihydroxyethylami) nitration reaction mixture was studied. The critical ignition temperature about different scale was obtained, and this temperature can be used as the base of enterprise process safety design.

Abstract: With the rapid development of transportation, the vulnerability of bridge under blast loading has more and more attracted people's attention. To ensure the safety of the bridge under the impact of blast loading is very important. This article describes the current situation of bridge structure antiknock research in China and other countries. What’s more, pointed out the shortcomings of existing research and presented that the antiknock research of bridge structure should combine numerical simulation with model test at the same time. This article researches the stress, strain and bridge damage rule of 1: 5 model of T-beam Bridge under explosion effect of small doses explosive.

Abstract: Bearing capacity and settlement are two important parameters in geotechnical engineering. The bearing capacity of circular foundations on sandy soils is important to geotechnical practicing engineers. Design of foundations includes soil parameters and bearing capacity of foundation. This paper presents the results of laboratory experimental model tests of circular footings supported on sand deposit under static load. The finite element software Abaqus is used to compare the results. The effects of the relative density of the sand (30%, 50%, and 70%) and the diameter of circular footing (75 mm and 100 mm) are investigated. It can be concluded that the experimental test results fit quite well with the results of numerical method.

Abstract: It is well known that a lot of concrete filled steel tubular (CFST) arch bridges were built in China. Thus it became a main bridge type. Its architectural design shows much novelty, while the structural design is always conducted based on the finite element (FE) model analysis. Meanwhile there is no professional code for design and construction of this type of bridge. To overcome these disadvantages, scaled model tests are preferable to evaluate the mechanical behavior and provide guidelines for design and construction of prototype bridges. In this paper, an irregular CFST arch bridge as the prototype was introduced and a 1/16 scaled bridge model was designed and constructed according to the similarity theory. The experimental study on the scaled model was aimed to simulate the construction stages and mechanical behavior under moving loads. The test results are used to make comparison with the construction monitoring and bearing-capacity load test of the prototype. The analysis shows that the experimental results of the scaled model are close to the measured results of the prototype. The scaled model test was proved to be valuable for the pre-camber setup of the arch rib and the tension optimization of the suspenders and for the operation safety.

Abstract: The stress distributions of the related anchorage zones are complicated under the large tonnage anchorage device. The safety and the crack resistance of the anchorage zone which exists due to the usage of are the critical part of the structural design. Do research on the general distribution regularity of stress of anchor-region by using ANSYS and gives the reason of the cracks occurred on web-plate.

Abstract: Soil arch plays an important role in the landslides reinforced by stabilizing piles . A method was presented to determine the range of soil arching ring. The method proposed was achieved by finite element program and the stress distribution of soil arch with different landslide thrust was analyzed. The results show that the thickness of soil arching ring is variable. The mid-span section of soil arching ring is the minimum. The arch ring becomes thicker from the mid-span axis to the arch feet. With the increase of landslide thrust, the soil arching ring becomes thicker and thicker. At last ,the monitoring data of a model test is studied and the results are consistent with that of numerical simulation.

Abstract: In this paper, an experiment in a quasi-static conditions was carried out on barge bow model with its cross sections simplified. The characteristics of the bow structure were studied experimentally and Finite Element Analysis (FEA) was conducted to compare with experimental results. The experiment was performed by a compression and shear testing machine and the model was axially collapsed by a rigid board. The collapse mechanisms, load-displacement curve and mean crushing strength were investigated. The study showed that basic collapse mechanism of barge bow was clarified in participates with inner diaphragms. Moreover, the accuracy of FEA to estimate mean crushing force were validated by comparing with experimental results.

Abstract: In order to acquaint the application of geological penetrating radar (GPR) in tunnel lining detection elaborately, the tunnel lining model involving diseases (voids, voids filled with water, zone filled with materials and cracks) has been researched with GPR (equipped with a 800MHz antenna). And on the basis of the finite difference time domain method (FDTD), the 2-D simulation model of tunnel lining with different diseases was established with the software GPRMAX2D for further research in 800MHz and 1400MHz antennae. Comparing the GPR images of the test model and the 2-D numerical model with the actual layout settings in the tunnel lining, the following results can be obtained obviously. GPR is impressible to steel, while the lower rebar is difficult to identify for the double-layer rebar; GPR equipped with a 800MHz antenna is appropriate to monitor the void, while the accuracy of the geological radar method is related to the shape, size, depth and water condition of the voids; the accuracy of GPR is almost 50mm for the 800MHz antenna , while it is 20mm for the 1400MHz antenna and cracks can’t be identify with the 800MHz.

Abstract: Transparent soil is a kind of material that can be used to observe the internal deformation under different conditions which has the similar characteristics with natural soil. This paper introduced the optical principles and the preparation of raw materials used to composite transparent soil. Stated the development of the transparent soil and summarized the main innovation achievements of the research trials around domestic and foreign. This paper also indicated that the existed tests mainly contrary to transparent sand while transparent clay is rarely involved and then proposed the study ideals and views about transparent clay.