Papers by Keyword: Experimental Test

Abstract: In order to overcome the low speed serial links of the bandwidth low, easy to produce decline, low rate of transmission characteristics, This paper design a transmission optimization system, In the system, this paper proposes a forward error correction and data compression transmission optimization combined method, Transmission optimization technology in recent years has been widely used in the field of network communication. Transmission optimization technology has been shown to improve the utilization rate of bandwidth, improve transmission efficiency. In this paper, the transmission optimization of the forward error correction technology has carried on the simulation test, And the analysis of experimental data were compared before and after the optimization, The experimental results show that the proposed transmission optimization method for low speed serial links the data transmission efficiency has been obviously increased . Transmission Optimization Technology Transmission optimization techniques include forward error correction, data compression, and adaptive protocol of three parts, combined guarantee bad message transmission efficiency in transmission environment. This paper mainly studies the transmission on the wireless communication channel environment serial links optimization techniques. Bandwidth Compression Technology. Bandwidth compression is transmitted through compression technology after traditional smaller packets, such as real time transmission of packets is more than the number of packets before compression, so as to realize the goal of improving transmission speed. Bandwidth compression technology is not really to data compression, because the network of packet size and length size has strict rules, if the size of the data has changed, and is also change his nature. So the true meaning of bandwidth compression is part of the data in other ways to replace, including cache corresponding not change information data or with short data instead of long, Then after receiving inverse substitution process, complete the purpose of saving bandwidth. The most commonly used three kinds of compression algorithm: Huffinan coding, dictionary coding and arithmetic coding [.

Abstract: The paper is dedicated to describing of experimental processes and experimental technique needed for realization of experimental tests of a bridge. The dynamic loading test was carried out on the monitored bridge. The time courses of bridge vertical displacements were registered. The power spectral densities of obtained records were used for determination of the basic natural frequency. The experimentally obtained results were compared with numerically obtained ones .

Abstract: In the past two decades, CFRP had been used to strengthen and repair r.c. structures and recently it is also employed to strengthen historical or monumental buildings constituted by masonry structure. However, premature failure due to debonding of the FRP is one of the important issues still to be resolved. Numerous word wide research studies have dealt with the debonding problem in r.c. structures but only a few works were carried out in the masonry structures area. So, the study of the global behaviour of the reinforced masonry element seems to be very useful, both for a congruous design and to verify the strengthening strategy. To this aim, this paper summarizes the debonding phenomena between C-FRP strip and natural calcareous rock brick, employed in our buildings, by means of a testing investigation. Two different kinds of anchorage were designed and employed for the tested samples: standard and reinforced anchorage. The experimental tests carried out on the specimens permits us to compare the effective bond length, with the one obtained by International rules and especially with the Italian CNR-DT200/2004 formulation and to say that the effective bond length dictates by the rules undervalues the experimental data. The data obtained permit us also to know the shear-slip delamination curve useful for the numerical investigation, as well as both the failure mode and the "II mode" fracture energy.

Abstract: Introduced the basic situation of aircraft tanker truck, carried out the performance tests of the tanker truck with ZX120-100 and ZX120-100-GY self-suction oil pump in the plateau. The test result shows that the self-suction capability of ZX120-100-GY centrifugal oil pump is better than ZX120-100 centrifugal oil pump, and refueling performance of 2004-12000 aircraft tanker truck with ZX120-100-GY centrifugal oil pump is good which can afford the demand of the aircraft.

Abstract: The selection of mix proportion is the process of choosing suitable ingredients of concrete and determine their quantities with the object of producing as economically as possible concrete of notably strength. The current paper deals with the mix design of both an HSC and HSFRC constituted by volcanic aggregates from the quarries of Eastern Sicily in Italy. The mix design was carried out on eight different concrete mixtures by using the theoretical model developed by Feret – De Larrard’s and it is capable of simulating the experimental compressive strength. The HSFRC mixtures consider different volume fractions of fibers equal to 0% (HRC), 0.5% and 2% (HSFRC). Straight Polyvinylalcohol (PVA) and hooked-end steel fibers (ACC) were the two types of fibers employed in the study. Compression and tensile tests were carried out on specimens performed according to UNI codes in order to validate the mixture proportion method adopted. The HSFRC (0.5%) mixtures did not show great differences in mechanical performance by any variation of the fiber type (steel or PVA). The mechanical properties obtained by experimental tests give back a very good accordance with the theoretical prediction of the mix design procedure adopted, and with the data reported in the literature in terms of toughness.

Abstract: Firstly, the previously developed numerical model for static analysis of spatial concrete frame structures is briefly described. In this model, cross-sections of structural elements can be of arbitrary shape and formed by various materials, with arbitrary normal stress normal strain relations. This model only includes the effect of normal stresses on the structure failure. Here, it was improved by including the effect of shear forces on the failure of reinforced concrete beam elements. Shear bearing capacity of reinforced concrete section includes the concrete capacity, as well as the shear bearing capacity of longitudinal, transversal and inclined reinforcement bars. The developed numerical model and appropriate software were verified on experimental shear test of a concrete beams. Good agreement was obtained between the experimental and the numerical results. However, further verifications of the presented numerical model are needed.

Abstract: This paper reports the results obtained during a research project funded by the Italian Government and involving several Italian Universities (PRIN INTEMA). The activities have been focused on side impact bar manufacturing by means of Tube Hydroforming process (THF). Punch movement paths and fluid pressure curve were optimized by means of FEM software (LS-DYNA) to guarantee tube sealing and material feeding during the tube deformation. The side impact bar geometry was optimized till reaching the shape guaranteeing the obtainment of safe parts with the best compromise in terms of final part geometry and thickness reduction. Different fluid pressure and punch movement paths were investigated. Once accomplished all the simulations and identified the best working solution, experimental tests were performed setting the process parameters according to the values defined during the simulation phase. Good agreement between FEM and experimental results were highlighted.

Abstract: This paper presents a laboratory test to characterize the pavement performance of asphalt mixture containing polyolefin/ethylene copolymer modifier. The modifier is directly added into mixture like aggregates and is not necessary to modify the asphalt binder firstly, which is different with conventional modifier and is so-called dry process. Based on the aggregate grade of AC-13 mixture, the mechanical properties of polyolefin/ethylene copolymer modified hot mixtures asphalt (dry process) were studied by experimental tests, which include the high-temperature stability and water stability. The test results indicate that compared to the SBS asphalt mixture the dynamic stability and TSR improved 66% and 2.3% respectively, when the addition of RK300 is 0.3%.

Abstract: The original concept of self-centering system was first proposed under the PRESSS research project in 1991 in UC San Diego. The particularly promising and effective structural solution was initially defined as hybrid system in literature and then self-centering system recently. In the ductile connection of self-centering system, inelastic demand is accommodated through the opening and closing (control rocking) of a pre-existing gap at the critical interface, with no consequent damage such as the plastic hinges in traditional structural elements. This paper provides an overview of the recent advances of self-centering system, especially for bridge piers, to summarize several analytical models and experimental tests that were widely recognized. Besides, a brief introduction of the study conducted by Tsinghua University is presented, including a stiffness degrading analytical model and a series of experimental tests.

Abstract: Research on progressive collapse has advanced greatly in the past forty years. Motivated by heightened research interest around the globe stemming from recent high profile events, the rate of progress has been especially rapid in the past decade. Research in this area has been primarily enabled by massive improvements in computational simulation tools and hardware as well as structural testing at a scale and level of sophistication never seen before. While the research effort shows no signs of slowing down, several agencies have already undertaken large codification efforts in an attempt to synthesize the rapidly growing knowledge base into practical and meaningful guidelines for collapse-resistant design. This keynote paper presents the state-of-the-art in progressive collapse research. The paper sheds light on several topics including: methods for assessment of structural robustness; methodologies for enhancement of system collapse resistance; probabilistic models for progressive collapse risk assessment; and current trends and research needs, which discusses current gaps in our understanding of progressive collapse research and identifies research efforts needed to address them.