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The purpose of this research is to compare the results of utilising the manual approach vs STAAD Pro to assess and design a roof for a circular water tank that is lying on the ground. Two groups were compared using a t-test based on an independent sample. Both groups, 1 (the control) and 2 (the experimental) each have 9 samples total (STAAD Pro). Using G power of 50 and alpha of 0.05, we were able to acquire an accurate sample size of 18. Manual and STAAD Pro were used for the analysis and design. Shear stress, bending moment (BM), and deflection were all tested using an independent t-test, and the results indicated no statistically significant differences between the groups (p-values of 0.25, 0.88, and 0.20, respectively; p>0.05). Since p>0.05, it may be inferred that there are no statistically significant differences between the manual and STAAD pro approaches to design. With less work, STAAD Pro produces outcomes that are on par with those of a solution developed in accordance with the requirements of the IS code. Thus, STAAD Pro is an effective tool for modelling, analysing, and designing lightweight buildings. [ABSTRACT FROM AUTHOR]

Research on the compression behavior of concrete has been widely carried out, on the other hand, information about the behavior of concrete in tension was limited. The existing concrete tension tests are the splitting, direct tensile, and rupture tests. These methods provide information on the tensile strength of concrete through concrete tension stiffening tests. This paper aims to elaborate on the experimental study to develop and construct the equation of concrete tensile strength based on the tension stiffening effect mechanism. The basic principle of this newly proposed method was the composite action between steel and concrete. The straight and continuous steel bar was embedded in concrete to ensure no eccentricity that could interfere with research data due to the bending moment. 45 Specimens made from cylinder concrete with 101.6 mm diameter and 450 mm length, steel bar embedded at the center of the section. Three concrete mixes with actual compressive strength of 31.66 MPa, 40.27 MPa, and 46.60 MPa and steel bar diameters of 15.9 mm, 18.7 mm, and 21.7 mm were used as variables. The test was performed by applying an incremental tensile loading at both ends of the steel specimen with a load rate of 5-10 kN/minute to obtain a force-displacement relationship. The curve must be lessened with steel bar response to get the load-displacement of tension concrete, and then by dividing load with concrete area and displacement with the length of both LVDT can be generated stress-strain of tension concrete. This study shows that the tension-stiffening effect is affected by the reinforcement ratio. Where the reinforcement ratio increases, the tension-stiffening decreases. The steel bar to concrete-area ratio higher tends to more cracks. The concrete tensile strength of this research is taken from the stress of the first crack indicates very close to the direct tensile test but slightly higher. [ABSTRACT FROM AUTHOR]

The paper studies pure bending of a strip (beam) containing through crack which is perpendicular to its axis and asymmetrical about the one. One of the crack tips is in the compressive stress zone and crack faces are in smooth contact near it. The other one is in the tensile stress zone and there is a striplike plastic zone on the crack prolongation line near this tip. The solution is reduced to linear conjunction problems using methods of complex analysis and complex potentials. The length of crack faces contact zone, the length of crack tip plastic zone and crack tip opening displacement are evaluated. Their analytical solution is found. The system of transcendental equations for calculating the length of crack tip plastic zone and parameter, that characterized the length of crack closure zone are established. Formula for calculating the crack tip opening in noncontact tip and dependencies for the stress tensor components on the line, where the crack located are wrote. Numerical analysis of crack tip opening in her noncontacting tip and the length of crack tip plastic zone from reduced external load and location of crack center relative to the axis of the strip (beam) is done. The parameter, that characterized the length of crack closure zone doesn't depend from external load is find numerically and a simple formula for its determination is given. The critical value of the bending moment of fracture of the beam (strip) with the contact crack is estimated based on the δк-model of fracture of crack bodies. [ABSTRACT FROM AUTHOR]

The paper provides a detailed analysis of the work under load structures of clamp scaffolds and systematizes the features of considering loads and impacts when performing strength calculations. The article analyzes the stress-strain state of free-standing forests. An algorithm for calculating free-standing forests is proposed, considering the features of structural schemes of blocks that are not specified in the normative literature. Based on the results of the analysis of data from a series of numerical experiments, constructive measures are proposed to ensure the load-bearing capacity, rigidity and stability against overturning of spatial blocks of free-standing forests, which will allow installing blocks with a height-to-size ratio exceeding 3,5:1 in open areas (outside buildings and structures) without attachment to existing structures. Considering the eccentric connection of scaffolding elements leads to a complex deformation of columns (oblique eccentric compression), i.e. to increase in the resulting bending moments up to 100%. Using of diaphragms in the design of free-standing clamp scaffolds blocks reduces the displacements of the block nodes by up to 16% in comparison with blocks without a diaphragm Another feature of scaffolds is that they are used for not only classic buildings and structures and for the maintenance and repair of various space stations and aircrafts. [ABSTRACT FROM AUTHOR]

In this paper a static analysis of Indian Railway track is presented. The track is considered to be a beam on elastic foundation of Winkler type. The Winkler type foundation is presented here in two ways: Continuous and discrete support form. Indian Rail profile R60 data are applied to obtain analytical and numerical results. The governing differential equation and finite element formulation of the beam is taken into the account. Two loading pattern is considered: single point load of 98 KN corresponding to a single wheel and two pairs of wheel loads of same magnitude at each of the contact point. The results obtained from the two formulation provide track displacement, bending moment and shear force variation in an around the contact region. These results for track displacement are simultaneously compared with those obtained from Euler-Bernoulli beam theory and Timoshenko beam theory. The analysis indicate discrete elastic support assumption offer closer matching with experimental results available in literature than those from continuous elastic support condition. This study can be viewed as a foundation for future dynamic and vibration analysis of the track. [ABSTRACT FROM AUTHOR]

In this issue is considered the developed computational model on the basis of finite element method, which is first of all provided the calculation of stress-strain state of embankment and culverts. This method describes real properties of soils and road culverts of various shapes under effect of transport loads. The comparative analysis of results of model calculations showed the applicability of developed method to carrying out a numerical experiment for structures of culverts. As a result of calculations, the internal forces in structures of culverts (bending moments, transverse and normal forces) and stresses in the soil surrounding of them are determined. [ABSTRACT FROM AUTHOR]

A theoretical study on the shape instability of a slightly deformed bubble encapsulated by a viscoelastic membrane in an ultrasound field is performed. The membrane effects of the inplane stress and the bending moment are incorporated into the traction jump condition at the bubble surface. The spherical motion of the bubble is numerically obtained by solving the Rayleigh-Plesset equation with the elastic stress. The deflection therefrom is linearized and expanded with respect to the Legendre polynomial. Two amplitudes for each shape mode are introduced because the membrane has mobility not only in the radial direction but also in the tangential direction. A simple expression for the natural frequency of shape mode is derived. Stability diagrams for the higherorder shape mode are mapped out in the phase space of driving amplitude versus driving frequency. The most unstable driving frequency is found to satisfy an integer multiple relationship with twice of the higher-order natural frequency. This finding is justified by a fact that the system with a boundary layer approximation is simplified into Mathieu's equation. Liquid viscosity plays an important role in the shape stability due to the vorticity generation on the deformed membrane. [ABSTRACT FROM AUTHOR]

In this paper, a method is proposed to analyse the seismic response of single piles under nonlinear soil condition. It is based on the Winkler foundation model formulated in the time domain, which makes use of p-y curves described by the Ramberg-Osgood relationship. The analyses are performed referring to a pile embedded in two-layer soil profiles with different sharp stiffness contrast. Italian seismic records are used as input motion. The calculated bending moments in the pile are compared to those obtained using other theoretical solutions. [ABSTRACT FROM AUTHOR]

The design of flexible earth retaining structures under seismic loading is a challenging geotechnical problem, the dynamic soil-structure interaction being of paramount importance for this kind of structures. Pseudo-static approaches are often adopted but do not allow a realistic assessment of the performance of the structure subjected to the seismic motions. The present paper illustrates a numerical parametric study aimed at estimating the influence of the dynamic soil-structure interaction in the design. A series of flexible earth retaining walls have been preliminary designed according to the requirements of Eurocode 7 and Eurocode 8—Part 5; their dynamic behaviour has been then evaluated by means of dynamic numerical simulations in terms of bending moments, accelerations and stress state. The results obtained from dynamic analyses have then been compared with those determined using the pseudo-static approach. [ABSTRACT FROM AUTHOR]

A new method for evaluating and compensating springback is presented. It is based on prediction of the change in curvature after springback by the mechanics of the elastic recovery. Starting from the nodal coordinates and the stress and strain distributions predicted by the FEM simulation at the beginning of springback, it first calculates the curvature and bending moments on the stamped sheet surface. Then, by modifying bending moment and curvature of sheet surface as well as process conditions it predicts an ideal sheet state at the beginning of springback. While predicting the ideal sheet state, it solves optimization problems to minimize springback defects with the aid of shape defect evaluation software named “NXT Defect Evaluator”. The springback process from this ideal state is expected to generate the desired shape. Therefore, the ideal sheet shape is helpful when designing compensational tools and renewing the FEM model. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The grazing angle variability of bent elliptical microfocusing mirror with variable width mirror substrates was investigated. It has been shown that with properly adjusted bending moments, a bent elliptical microfocusing mirror optimized for certain optical configuration can be well used for a range of grazing incident angle. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Experiments have shown that the thickness of shear bands depends upon the mean particle size. These observations suggest that a proper continuum representation of granular behavior must be augmented in a manner that introduces a characteristic length scale. Such generalized continua include micro-polar continua (which involve couple-stress or higher-order stress) and strain-gradient material models. The paper presents the results of DEM simulations that test whether such micro-polar or strain-gradient effects are present in granular materials. The 2D simulation experiments were conducted as “flexure tests” of roughly square assemblies of circular particles. The platens along two opposite sides were rotated to produce a fiexural curvature of the assembly between these sides. Particles along the rotating sides were constrained to translate and rotate in conformity with the sides; whereas, interior particles were free to adjust their movements so that their local equilibrium was maintained. The constraining movements of the platen particles were produced by applying external forces and moments. By measuring incremental forces and moments, we compute the incremental bending moment on the particle assembly. This incremental moment is compared with that of a simple classical continuum. After being compressed to near the peak strength, the bending stiffness is significantly greater than would be computed from classical stiffness moduli. That is, at large strains, granular stiffness depends, in part, on the gradient of strain, not just the strain alone. The results are consistent with micro-polar media or with a strain gradient-dependent material. [ABSTRACT FROM AUTHOR]