Applied Mechanics and Materials Vol. 376

Abstract: The rigid limit equilibrium method can be used to analyse the slope stability under the earth penetrating weapon explosion. The explosion seismic inertia force is equivalent by the equivalent static loading method and seismic attenuation is also taken into account, and then the calculating formula is got. The calculation of the example indicates that the stability coefficient increases as the potential sliding rock mass volume increasing and the critical sliding point is corresponding to the maximum sliding rock mass volume. The impact point and explosion center depth influence the slope sliding.

Abstract: Suspended centrifuge which is the post-treatment equipment during the production process is widely used in the sugar manufacture industry .Sieve basket is the key parts of the suspended centrifuge because its structure, shape and processing property will not only affect the production and use cost of the suspended centrifuge , but also will largely determine the service life of the centrifuge. Its very important for the optimization of the sieve basket structures every parameter which needs to have a deep analysis for the stress intensity and displacement size of sieve basket when it works under the condition of full load.

Abstract: Through many samples of 1000mm² large section conductor creep test, the creep characteristics of 1000mm² large section conductor is summarized. Temperature reduction value for transmission line stringing construction of 1000mm² large section conductor is determined as 30°C based on creep value and conductor characteristics, which will give some reference to the real projects.

Abstract: Gap-based polyurethane elastomer (GAPE) with different hard segment contents are synthesized with 44-Diphenylmethane diisocyanate (MDI), 1,4 butylene glycol (BDO) as hard segments and GAP as soft segments. Dynamic mechanical analysis (DMA) is applied to investigated the dynamic mechanical properties and the mechanical properties of GAPE are studied by materials laboratorial instrument. The results show that GAPE-2 with 33 wt% hard segment has better mechanical properties, of which the tensile strength is 11.3MPa and elongation at break is 460.5%.As shown in DMA, T _g of GAPE-2 is-18.4°C, and the low-temperature fragility parameter and activation energy of GAPE-2 are lower, 55.6 and 271.0 KJ·mol^-1 respectively. Elastomer with good stiffness and flexibility is obtained.

Abstract: The investigation of the present work brings out the effect of Raichur Fly Ash (RFA) and Nyveli Fly Ash (NFA) on California Bearing Ratio (CBR) of two extreme soils, Black Cotton soil and Red earth. CBR of soil fly ash mixtures assume great importance in their use for road construction. CBR are modified depending on the soaking condition. Thus the CBR of soil fly ash mixtures are determined as compacted and also in soaked condition. CBR of fly ashes under un-soaked conditions exhibit higher values because of additional resistance from capillary forces, for instance when 20% of RFA is added to black cotton soil under Unsoaked condition, blend has shown CBR of 10.38% as found in results. In presence of water fly ashes loose capillary forces and gives lesser CBR, where blend has shown CBR of 4.56% for addition of same quantity of RFA. Same additions when it is made to Red earth, the corresponding results are 11.74% for Unsoaked and 4.74% for soaked conditions. In cases of fly ash with calcium, they generate cementitious gel and impart strength to mix, which increases the CBR even in soaked condition [1]. Addition of cement to RFA and lime to NFA, the resistance of blends increases. CBR of soils with RFA exhibits pronounced peaks at fly ash contents of 20% and 80%. This is due to predominance of skeleton of soil and fly ash respectively. The CBR of soil with NFA addition further increases with soaking. CBR of soil with NFA addition increases continuously with fly ash content. The results reveal that when same 20% NFA is added to soil, the CBR of soil in unsoaked condition is 11.46%, whereas for soaked condition it is 23.62%.

Abstract: A dent in a pipeline is a permanent plastic deformation of the circular cross section of the pipe. This paper discusses numerical results obtained from finite element (FE) simulation of pressurized pipe subjected to radial denting by a rigid indenter. Dent produced by rectangular shape indenter is assessed and the strain distribution of the pipe is investigated. The effect of internal pressure and dent depth on the distribution of strain is also studied. The results show that the circumferential and longitudinal strains increase with increasing the internal pressure and the depth of the dent. Numerical results are compared with an empirical theoretical model in order to demonstrate the accuracy of the analysis.

Abstract: Simulation analysis was made with the factors of the base paper and the structure of honeycomb paperboard by means of ANSYS after abstract and simplify honeycomb paperboard model. The results show thatfactors of quantification of surface paper, cell length, paperboard thickness and aperture ratio all have a great effect on the mechanics performance of honeycomb paperboard. With the increase of quantification of surface paper, longitudinal and transverse platform stress both rise gradually. With the increase of cell length and paperboard thickness, the platform stress and peak stress under different compression direction of honeycomb paperboard all decrease, providing a reference for the study of numerical simulation and mechanical property tests.

Abstract: Plasma cladding experiments were carried out on Q235 steel with Fe-Cr-Ti-C powder. Microstructure and micro-hardness of the composite coatings were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA) and micro-hardness tester. The results indicated that the grains of the cladding coatings with Ti are much finer than that of the Fe-based cladding coating without Ti. Compared with the cladding coatings without Ti, there are more shingle crystals in the cladding coatings with Ti and the hard phase (Cr,Fe)₇C₃ of the eutectic in the coatings increase gradually. The average hardness value of the four cladding coatings is respectively 486.5 HV0.1and 558.8 HV0.1.

Abstract: Magnetorheological elastomer (MRE) is a novel kind of magnetorheological materials and has been successfully used to control the structure vibration due to its property of variable stiffness under different magnetic field. In order to improve the properties of MRE, it urgently needs to investigate the preparation methods of MRE and build a corresponding test system to evaluate the performance of MRE in different operating modes. In this paper, different magnetic devices for preparing MRE were studied and designed, and the material was fabricated by the permanent magnets with additional permeability equipment at last. Then, according to the SDOF principle, a novel test system was built in order to investigate the mechanical properties of MRE, and exact close-form expressions of the stiffness, loss factor and other mechanical parameters of MRE, under different magnetic field, have been calculated to analyze the properties of MRE.

Abstract: In this study Cu-Ag or Cu-Cr layer was sandwiched by Ti and Fe plates and the three layers of Ti/Cu-8Ag/S20C were clad by High Pressure Torsioning(HPT). The effect of post-HPT heat treatment on the interfacial reaction products and the mechanical performance in Ti/Cu-Ag/S20C and Ti/Cu-Cr/S20C clad material were studied. Cu₄Ti₃ and Cu₄Ti Intremetallic compound layers were observed at the Ti/Cu-Ag and Ti/Cu-Cr interfaces in the clad heat-treated at 500°C where as no intermetallic compounds were observed at the Cu-Ag/S20C and Cu-Cr/S20C interfaces. The strength of as-HPTed Ti/Cu-8Ag/S20C is much higher than that of Ti/Cu-1Cr/S20C. The strengthening mechanism of Cu-Ag deformed severely is the interface and strain hardening in which dislocations are deposited at the Cu/Ag interfaces and can contribute to the strengthening of the clad composite just after HPT processing, rendering the high strength just after processing. In both clad composites, the strength and ductility increased after heat treatment at 350°C, which are likely caused by the enhanced bonding at the interfaces.