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The article is devoted to the lateral-torsional buckling of elastic beams loaded with a potential moment. Such problems were previously investigated in a linearized formulation. The prebuckling deformations of the beam is not considered in this setting. We use the nonlinear geometrically exact beam theory and an exact non-linear solution in our article. The exact spatial stability functional and stability equations are obtained by the variation calculus. The exact value of a critical moment for the cantilever beam was obtained. [ABSTRACT FROM AUTHOR]

The article considers the stability of an eccentrically-compressed I-beam rod under the combined action of axial force, bending moment and bimoment. The theoretical analysis of stability is carried out and the dependences of the bearing capacity for such rods are obtained, taking into account the constrained torsion (warping). Theoretical and numerical calculations of eccentrically-compressed cantilever rods of various flexibilities are discussed. The numerical calculations are performed taking into account geometric and physical nonlinearities. The elastic-plastic properties of steel are realized using a unified diagram of the work of steel class C245. The bearing capacity is estimated, which is obtained in three ways: theoretically, numerically (calculations using the Femap with NX Nastran computing complex) and using the normative methodology for calculating eccentrically-compressed rods. Accordingly, the results of a comparative analysis of I-beam stability obtained by these methods are presented. Therefore, it is concluded that ignoring stresses during constrained torsion leads to significant errors in determining the load capacity on an eccentrically-compressed twisted thin-walled rod of an open profile section. [ABSTRACT FROM AUTHOR]

The purpose of this study is to compare the strength, crack resistance and deformation of T-section beams made of reinforced concrete, rubber concrete and fiber rubber concrete. Rubber concrete (or abbreviated rubcon) is a highly effective composite polymer concrete based on liquid rubber, which has favorable physical and mechanical characteristics, as well as almost universal chemical resistance to aggressive media. This article presents the results of testing prototypes of T-beams using the following procedure. The beams were tested for bending by two forces applied in thirds of the span, increasing until failure. As longitudinal reinforcement, rods of class A500C were used. As transverse - Bp500, 5 mm in diameter, with a pitch of 50 mm. Fiber reinforcement is represented by steel fibers (ratio of diameter to fiber length 1/100), located randomly throughout the volume of the experimental beams. The section of the beams is assigned taking into account the requirements of SP 63.13330.2018 "Concrete and reinforced concrete structures": length - 1400 mm; web height - 95 mm; web width - 60 mm; flange height - 25 mm; flange width - 240 mm. It was found that the value of the destructive experimental bending moment in reinforced concrete beams is 1.20 times less than in rubcon and fiber rubcon beams. It was revealed that the most effective use of the strength of a normal section before reaching the maximum allowable deflection is observed in a rubcon beam (BKT240x95x25-2x10). [ABSTRACT FROM AUTHOR]

The article presents the main provisions of the analytical method for calculating elasticity on the action of dynamic loads from industrial equipment. Simple dependencies make it possible to quickly and with a sufficient degree of accuracy calculate structures for the specified loads. Thin foundation slabs have a high load-bearing capacity and allow significant savings in material and simplification of their construction. The underlying floors of industrial buildings are widely considered as foundations for equipment, which in turn makes it possible to increase the versatility of buildings. The dependencies presented in the article make it possible to calculate the floors of industrial buildings as endless slabs on an elastic foundation. The analytical method is based on the construction of impulse transient and transfer functions using the known relationships between them. The axisymmetric problem is being solved. The equation of motion for a plate on an elastic foundation with additional masses is written in polar coordinates and reduced to a system with two degrees of freedom. As examples, the calculations of slabs on an elastic foundation for the load from vertical reciprocating compressors of several types are given. Deflections and bending moments were calculated as a function of time depending on the distance to the center of the track. The calculation results show that the installation of such equipment is possible directly on the underlying layers of the floors. The vibration isolation device significantly reduces the amplitude values of the displacements and accelerations of the plates, while increasing the movement of the equipment itself. [ABSTRACT FROM AUTHOR]

The work of a reinforced concrete beam lying on an elastic foundation is considered, the deformation characteristics of which are described by a model with two Vlasov-Pasternak bed coefficients. The bed coefficients are considered as stationary random normally distributed functions of the x coordinate. Strength characteristics of concrete: cube strength and concrete tensile strength are assumed to be random variables with Gaussian probability density distributions. The concentrated forces approximating the columns of the building are applied at regular intervals and are assumed to be random normally distributed values. After the formation of cracks in the sections under concentrated forces in the beam, areas with a reduced bending stiffness are formed, and therefore the stiffness of the beam becomes variable along the length of the beam. The solution of the differential equation of bending of a beam with variable stiffness lying on an elastic foundation is proposed to be sought by a variational method minimizing the functional of the additional energy principle. The deflections of a beam with variable stiffness will be approximated by a function that satisfies the boundary conditions and the equilibrium condition. From the equality of the deflections of a beam with constant equivalent bending stiffness and deflections of a beam with variable bending stiffness due to cracking, the constant equivalent stiffness and its statistical parameters are determined. Knowing the constant equivalent bending stiffness of a concrete beam and using the known solutions of the bending equation of a beam lying on an elastic foundation with random properties, it becomes possible to find the probabilistic parameters of bending moments and shear forces and to determine the probability of the onset of limit states of the beam along the normal and inclined sections. [ABSTRACT FROM AUTHOR]

The article is devoted to the dynamic calculations of the elements of the box-shaped structure of buildings for seismic resistance, taking into account the spatial work of the box elements under the action of dynamic influences set by the movement of their lower part according to the sinusoidal law. The equations of motion are given for each of the plate and beam elements of the box-shaped structure of the building based on the Kirchhoff-Love theory. Expressions are given for the forces, moments, and stresses of the plate elements that equalize the movement of the box elements and the boundary conditions and the conditions for full contact in terms of displacements and force factors in the contact zones of plate and beam elements. The general solution of the problem is constructed by the decomposition method of the movement of the box elements according to their own forms using the method of finite differences. The calculation results were obtained in the form of diagrams over the height of the box of bending moments, plate elements working in bending, and shear stresses of plate elements. [ABSTRACT FROM AUTHOR]

Nowadays earthquake is an major problem for civil engineers for construction of different types of structure in heavily seismic zone. According to many researchers it is concluded that introducing supplemental damping to the structure can enhance the performance when the earthquake is occured. Many different types of dampers are use to prevent the building from seismic forces. In the present review provide varying types of studies proposed by many researchers to obtain various types of responses and results. Comparative study of different parameters which is nothing but bending moment, storey drift, storey displacement, storey shear are obtained. Author have modelled the structure with and without dampers, also by performing pushover analysis by using different position of dampers the optimum position of hinges are also to be find out by researchers. with the help of performance base design slip load of an friction damper is calculated can be calculated and distribute on each storeys. After modelling of friction damper the comparison of the structure response is studied. [ABSTRACT FROM AUTHOR]

The effect of reinforcement on the behavior of building structures such as houses, hotels, hospitals, offices, and others are very high. The existing BPJN Aceh building consists of 7 floors including the ground floor and the roof floor. This study aims to analyze the strengthening of building structures that are more economical with the addition of shear wall elements to the load combination and evaluate their stiffness. The main office building has 2 (two) towers in the form of an elliptical circle on the ground floor with a reinforced concrete structure, while on the first floor to the roof floor it is a steel structure. The calculation of the load used is following the data obtained from the planning consultant. Another factor that is reviewed is the displacement and force on the building before and after adding a shear wall to the structure of the center of the building and evaluating the efficiency of using WF2 as the main beam structure of the building. From the results obtained, the bending moment capacity of beams with shear wall elements is quite good. The ratio between load and resistance capacity ranges from 0.66 – 0.70. For the dimensions of the beam that have been reduced in this study, it turned out to produce a large bending moment of resistance. The ultimate moment in the shear wall is smaller because the system is stiffer and more robust. This is because of the lateral restraint, namely the shear wall. [ABSTRACT FROM AUTHOR]

Pile group with 2 × 2 configuration, subjected to lateral load is analyzed using three dimensional finite element model. In house program is developed in FORTRAN. Pile and pile cap is modeled using 20 node elements whereas soil is modeled using 8 node elements. Interface elements are having 16 nodes. The interface is modeled such that the gapping between the pile and adjacent soil is not allowed but the slipping is allowed. The nonlinear behavior of soil is modeled using the Von-Mises criterion and Drucker Prager (inner) criterion. The parametric study revealed the influence of pile spacing, soil modulus, and pile length to diameter ratio on the lateral displacement of pile group and the maximum bending moment. The results predicted by both criteria are compared. The trends shown by the results predicted by both criteria during the parametric study are similar. However, the results predicted by the Von-Mises criterion are higher than Drucker Prager (inner) criterion. [ABSTRACT FROM AUTHOR]

Pre-engineered steel structure systems are pre-designed and prefabricated in the pre-engineered building concept. The present construction method requires the best architectural beauty, excellent construction quality and speed, cost-effectiveness, and a creative touch. Pre-engineered steel buildings, for example, should be explored as an alternative building system. A Pre-Engineered Building (PEB) is a new concept that entails using a steel framework and optimizing the design while maintaining economic integrity. STAAD Pro will be used to analyze, design, and detail PEB structures with different loads in different regions. The applied load vs. deflection response, shear force & bending moment intensities, and stress concentration of pre-engineered building systems were used to evaluate the behavior of the structure. The tube cross section and Indian Standard Medium Weight Beam 350 of PEB for both column and rafter sections must be determined during the design stage. The optimization of PEB shall be presented in the report. [ABSTRACT FROM AUTHOR]

The purpose of this research is to compare and contrast the utilization of Rectangular hollow section and Tapered section for a multiple-bay industrial construction. The many comparison fields primarily demonstrate cost absorption, time consumption, structural weight, and economy of both portions. The shear force and bending moment are computed in this analysis. In Visakhapatnam, a model with a height of 8 meters, a roof angle of 5.71 degrees, and bay spacing of 7.4 meters was chosen, and a comparison was made between a Rectangular hollow section and a Tapered section with the same size of building. Finally, the results reveal that tapered sections are more cost effective than the RHS. The structural weight of the RHS and tapered sections without crane is less than the RHS and taper section with crane. [ABSTRACT FROM AUTHOR]

Nowadays, in our country earthquake has shown an increase in seismic zoning factor over various parts. India is divided into 4 seismic zones that are seismic zones 2,3,4 and 5, which covers over 60% of total land area. So, it has become very important to decide seismic reactions over structures in these particular risky zones. This review shows different research that has been carried out on this topic to get an overall idea where we stand currently and what more we can do. Comparison of result is done with respect to different parameters like displacement, storey drift, bending moment etc. Authors have used different types of methodologies and modern-day techniques like Response spectrum analysis and Equivalent static method to analyze a good range of structures and their seismicity. This review paper focuses on comparing manual calculations with a long range of advanced designing software data to finally get the optimum conclusion in the field of seismic analysis. [ABSTRACT FROM AUTHOR]

Long Span bridges are the need of the hour. Cable-stayed bridges are the best suited longer span bridges for about 1000 m of main span. This requires a great height of pylon. To eliminate great height of the pylon which poses construction difficulties, the concept of extra dosed cable stayed bridge came into existence. The change in interna l forces due to transformation from a cable stayed bridge to an extradosed cable stayed bridge is observed. The effect of height of the pylon to central span ratio of 0.25, 0.20, 0.15 and 0.10 over the internal forces is studied. The shift to an extradosed cable stayed bridge caused greater impact on the internal forces occurring in the deck. The live load patterns have a greater influence over the critical values of the internal forces and their location on the deck. Five live load patterns namely full span, left half, left side span, both sides pan s and central span loading conditions are considered for analysis to arrive at maximum values of deflection, bending moment, axial force in the deck. The maximum values of deflection, bending moment and axial force (compression) were found for both side spans loading condition only. [ABSTRACT FROM AUTHOR]

In this paper, we will calculate and compare parameters such as bending moment, axial force, and story drift in the context of "Analysis and Design of a Building with Floating Columns Using Different Slab Systems." The use of ETABSV18 was used to design and evaluate slab machines for G+5 buildings in seismic zone III with medium soil conditions. The slab scheme has been evaluated and laid out following IS 456-2000 and IS 1983-2002. The slab is designed for a single grid length of the column to see which slab systems with floating columns produce the best results, and the floating column placement is split into two cases for performance analysis. [ABSTRACT FROM AUTHOR]

In the last decades, several damages of pile-supported structures due to earthquakes have been reported. Soil-Structure Interaction (SSI) is an important factor to estimate the seismic loading on pile accurately and hence this is a vital question for engineers, how to model the SSI appropriately. The finite element method (FEM) can be used to estimate the seismic loading and predict the behavior of pile-supported structures during seismic excitation accurately. However, FEM is very complex and time inefficient. Researchers have proposed numerous alternative 1D spring models to consider the interaction between pile and soil, which are applicable for the beam on nonlinear Winkler foundation (BNWF) method. Among those spring models, PySimple1 is widely used and easily accessible by an open-source program - OpenSees. However, the shortcomings of PySimple1 is that it adopts the soil reaction curves (p-y curve) which were developed based on the static pushover tests or slow cyclic load tests on pile head. Recently, a dynamic p-y curve has been proposed as a hyperbolic function based on a series of centrifuged tests performed by Yoo et. al. 2013. This dynamic p-y curve is significantly different from the conventional static p-y curves in three aspects: initial stiffness of soil, ultimate bearing capacity of the soil, and overall shape of the curve as mentioned by Choi et. al. 2015. The proposed hyperbolic function is well adopted by soil-structures interaction research community for the development of dynamic nonlinear spring models, such as PySimple3, PySimple5, however the explanation for why the dynamic soil reaction curve is significantly different, is not properly explained. In this paper, PySimple1 and PySimple5 are considered for a detailed investigation of the difference between static and dynamic P-y curves. Results of a series of centrifuged test performed by Wilson in 1998 is adopted for comparison of each model. BNWF model of the experiment is prepared using PySimple1 and PySimple5. For PySimple1, an additional dashpot is defined, and by performing a parametric study, necessary damping values are quantified to obtain comparable results with experimental data. While the definition of additional dashpot is not needed for the model prepared with PySimple5. Equivalent linear models are also prepared and analyzed to point out the effect of the damping force on seismic loading on the pile during seismic excitation. It can be concluded that in seismic loading conditions the soil is in excited condition and hence it exhibits damping force on pile foundation. This damping force causes a significant difference between the static and dynamic soil reaction curves while preparing those soil reaction curves from the back-calculation of measured bending moment during the experiment. [ABSTRACT FROM AUTHOR]

Structure of diaphragm was defined as a transverse strengthener beam which was located between beams or girders to keep section geometry. It plays a significant role to provide the stability of bridge girders and to distribute the vertical and axial loads. The main objective of this study was to investigate the influence of construction transverse concrete diaphragms between T-beams at different distances on the dynamic and static behavior of T-beam bridge structure. The methodology of this research includes five case studies. The first case had no transverse diaphragms, the second case had transverse diaphragms at the supports of the bridge (abutment and piers), the third case had transverse diaphragms at the center of each span of the bridge, the fourth case had transverse diaphragms at 1/4 of each span of the bridge, and the fifth case had transverse diaphragms at 3 m of each span of the bridge. Three analysis methods were used to determine the dynamic responses by using finite element analysis method in CSI-Bridge ver. 20. These methods included modal analysis, time history analysis, and spectra responses analysis. Dynamic responses consisted of unloaded frequency, loaded frequency, and dynamic displacement. Static analysis was done to find static responses such as bending moment and vertical deflection. The results of dynamic analysis shown that the using of concrete diaphragms has not important effect on the improvement of unloaded frequency (natural frequency) in vertical and horizontal directions, but they had an important effect on the reducing of loaded frequency (vibration frequency) in vertical and horizontal direction and dynamic displacement. For static state, the construction of concrete diaphragms causes to increase bending moment and downward vertical deflection because of these cross diaphragms lead to increase in the dead load (self-weight of structure), resulting the increasing in the static responses due to service loads (dead load, prestressed load, and trucks load). Therefore, there is need to increase the prestressed load to resist the over load due to the construction of transverse diaphragms. [ABSTRACT FROM AUTHOR]

In the present study floating wind turbine combined with a wave energy converter is analysed deriving both wind and wave energy, and thus ensuring continuous supply of energy. The study combines a submerged tension leg platform (STLP) with heaving type point absorber wave energy converter (WEC). Submerged tension leg platform is stable in both transportation phase and operational phase. The point absorber WEC has a floater system having diameter smaller than the incident wave length. The floater tends to oscillate in one or more degrees of freedom (DOF) and absorbs energy by damping the floater motion and converting it into electrical energy. The study combines STLP floater with six wave energy converters in circular pattern. The time domain simulation is performed for the combined platform configuration using fully coupled aero-hydro-servo-elastic simulation tool FAST developed by NREL for different mooring line configuration. The analysis is performed to study the responses (surge, sway, heave, roll, pitch, yaw) for the combined configuration for wind and wave load conditions corresponding to North Atlantic Ocean. The tower base bending moment, shear force and the tension developed on the mooring lines of the combined platform is analysed along with the responses of the floating combined energy platform. The study performed is expected to provide an insight into the dynamic motions and structural integrity of the floating wind and wave concept under different survival conditions helping the designers to develop better design standards. [ABSTRACT FROM AUTHOR]

This paper displays the horizontal curvature (circular curvature) effect on deep beams using finite element analysis. Thirty-five reinforced concretes horizontally arched deep beams were analyzed. The parameters that were taken into consideration in the current work are the curvature angle (α) and beam height (H) while keeping one constant value for the beam length (L), i.e., different length to depth ratios (L/H). It is found that for L/H=2; the load capacity decreases by about 38-73% and 16-67%, respectively, when changing α from ∞ (straight beam) to 180 degrees, while torsional moments increase by about 74-174%. Negative bending moments decrease by about 13-56% when changing α from 30 to 180 degrees. The deflection decreases by about 0.1-1.8% when changing α from ∞ to 90 degrees. For L/H=2.5; The load capacity decreases by about 36-73% and 15-67%, respectively, when changing α from ∞ to 180 degrees, while torsional moments increase by about 73-168%. Negative bending moments decrease by about 14-57% when increasing α from 30 to 180 degrees. Decreasing deflection by about 4.1-5.9% when increasing α from 60 to 90 degrees. For L/H=3; load capacity decreases by about 34-73% and 14-68%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 71-161%. Negative bending moments decrease by about 15-58% when increasing α from 30 to 180 degrees. The deflection decreases by about 6-9.7% when increasing curvature angle from 60 to 90 degrees. For L/H=3.5; the load capacity decreases by about 34-73% and 14-69%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 70-156%. Negative bending moments decrease by about 15-59% when changing α from 30 to 180 degrees. Midspan deflection decreases by about 4.6-14.7% when changing α from 60 to 120 degrees. Finally, it is found that for L/H=4; The load capacity decreases by about 33-74% and 14-69%, respectively, when changing α from 0 to 180 degrees, while torsional moments increase by about 69-150%. Negative bending moments decrease by about 16-60% when changing α from 30 to 180 degrees. Changing α from 60 to 120 degrees leads to decrease deflection by about 9.1-19.4%. [ABSTRACT FROM AUTHOR]

The current work presents a parametric study for twenty-five reinforced concrete overhang curved deep beams using finite element analysis. The parameters that were taken into consideration are radius, height, width, compressive strength of concrete and number of supports. It is found that the max positive moments increase by about 2.8-4.4% when decreasing the radius of beam by about 16-33%. The max negative bending moment, max torsional moments and max deflection decrease by about 1.9-12.4%, 0.4-8.9% and 30-87%, respectively, when beam radius decreases by 16-66%, whereas load capacity increases by about 23-195%. The max positive bending moment, max negative bending moment, torsional moment and load capacity increase by about 32-128%, 30-124%, 31-125% and 31-127% respectively, when the beam height increases by 12.5-100%, while deflection decrease by about 9-18%. The max positive bending moment, max negative bending moment, torsional moment, load capacity and max deflection increase by about 32-147%, 29-134%, 30-138%, 32-146% and 1.2-4.9%, respectively when beam width increases by 12.5-50%. The max positive bending moment, max negative bending moment, torsional moment, load capacity and max deflection increase by about 17-70%, 15-61%, 15-63%, 17-69% and 0.1-0.4%, respectively, when concrete compressive strength increase by 33-166%. Finally, it is found that the max positive bending moment increases by about 32% when increasing number of supports by 33%. Max negative bending moment and capacity of load increase by about 17-60% and 106-763%, respectively, when number of supports increases by 33-133%. Torsional moment and max deflection decrease by about 0.8-16% and 29-78%, respectively when number of supports increases by 33-133%. [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]

Due to the large amount of input data, the calculation of bolted joints of beams with columns with end-plates is quite complex. Therefore, it is impossible to take any assortment of hot-rolled I-beams and apply the world's available calculation methods to it. It was found that for massive rolled profiles, the calculation method used in the EU gives significant overstatements in the bearing bending moment for some combinations of beams and columns. In addition, the existing methods do not take into account the actual final stiffness of the column when calculating the end-plate, and the stiffness of the end-plate when calculating the column flange. A universal prototype of the 8-bolt connection has been created, which is applicable for beams and columns of almost any size. For various combinations of beams and columns, 986 FE-models were created. Taking into account the available test results, analysis was carried out and criteria for limit state of bolted joint were formulated: according to plastic deformations in steel, according to stress in bolts, according to gap opening between column flange and end-plate. A modified method for calculating joints has been developed, which takes into account the ratio of the thickness of the column flange and the end-plate. [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]

The paper is devoted to developing a technique for evaluation of the stability of the railway tank boiler shell under the action of outer overpressure due to vacuum inside the boiler. The tank boiler is represented as a cylindrical shell with bottoms in the form of membranes absolutely rigid in their plane. The technique is based on the application of the moment theory of shells, the Lagrange variational principle, the approximation of displacements in the form of double Fourier series and matrix operations. A critical state before the stability loss is under consideration. Taking into account the outer pressure, the additional potential energy of deformation is defined as the work of additional bending moments on curvature change deformations when there is a non-axisymmetric deformed state. In the resolving system of equations based on the condition of the total energy minimum, the additional potential energy contributes in the form of an additional stiffness matrix and the vector of the right-hand side is zero. Due to the orthogonality of trigonometric functions during integration, the system decays into individual harmonics. For each combination of the harmonics the problem of eigenvalues is solved; as a result, the critical values of the outer pressure are found, as well as the corresponding forms of stability loss. The developed technique was verified according to the FEM results. The stability of the petrol tank-car boiler shell was studied. It was established by the calculations that there is an additional value of the critical pressure that differs in an outward direction and in an unrealistically high level. An attempt is made to establish the physical meaning of the additional solution. [ABSTRACT FROM AUTHOR]

In article the design procedure of the bending moment and curvature in a plastic zone of elastic-plastic calculation of the framework of the cabin of the tractor is offered. The offered method procedure of the bending moment and curvature in a plastic zone together with the known methods of calculation of an elastic zone allow with count deformation of the design of the framework with an accuracy, sufficient for the framework of cabins of the tractor. [ABSTRACT FROM AUTHOR]

In this paper, the empirical relationships are provided to predict the ultimate flexural resistance and the rotational capability of I-shaped aluminium alloy beams subjected to non-uniform bending moment. Starting from the parametric analyses carried out by means of FEM simulations, the final formulas are obtained as function of the main geometrical and mechanical parameters of aluminium beams. [ABSTRACT FROM AUTHOR]

The main aim of this research is to study the structural behavior of composite steel- concrete beams under the influence of variation of the reinforcement ratios in the concrete slab once, and with changing the degree of connection at other once. As well as conduct a comparative investigation in behavior and stiffness between specimen exposed to hogging moment and those that experience sagging moment. By presenting an experimental study. The use of additional reinforcement bars led to significant influence on the behavior of beams such as deflection, ultimate load, strain, slip and mode of failure. The ultimate load is increased by (11.51%), (40.29%), (54.67%) and (65.46%) when the reinforcement force ratio increased from 0.145 of control specimen to 0.24, 0.45, 0.68 and 0.90 respectively, while it was decreased by (6.52% and 7.83%) when the degree of connection decreased from 1.0 of control composite beam to 0.5 and 0.0 respectively. In general, the failure of reinforced specimens by additional bars compared with control was buckling in steel beam instead of gradually cracking of concrete slab. Whereas the failure of non-composite specimen shifted to crashing in bottom surface of concrete slab compared with the specimen have full composite action which failed by lateral torsional buckling in bottom flange of steel beam. [ABSTRACT FROM AUTHOR]

The carpenter tape is a thin spring-steel strip, preformed to a curved cross-section, which can be straight when being used for measuring. In this paper, we investigated the behavior of straight steel with carpenter tape geometry under the bending moment by simulation using Inventor software. This study used 3 points bending with applied force is 70 kN and the support length is 40 mm. The dimension of carpenter tape is length is 17 mm and 50 mm in width. The variable of radius used is 5.7 mm; 4.9 mm; 3.8 mm; 2.8 mm; 2.4 mm. From the simulation, we found that the high radius of carpenter tape geometries has higher bending tolerance and higher safety values. [ABSTRACT FROM AUTHOR]

Divergence and reversal speed are parameters related to the static aeroelastic behavior. While the former deals with the general stiffness of the aircraft, the latter is the main consideration for ensuring the good performance of the control effectiveness. Both of them are important and affected by wing flexibility. In this paper, the static aeroelastic analysis of solar-powered UAV has been conducted. The aerodynamic load is calculated based on the strip theory which involving the discretization process. The full model of the aircraft is proposed to analyze the effect of the trim condition on the divergence speed. While the steady roll rate assumption is made to construct the rolling effectiveness calculation. The results were then compared to the fixed root single-wing model to deduce the relationship between both of them. The lift distribution along spanwise is also presented in the case for calculating the root bending moment and tip twist angle. [ABSTRACT FROM AUTHOR]

Multi story Reinforced concrete cement Structure exposed to hazardous earthquakes. It was discovered that main reason behind failure of RC building is irregular distribution of mass, stiffness and strength or because of irregular geometrical arrangements. In reality, many existing structures contain irregularity because of useful and stylish prerequisites. However, past earthquake records show the poor seismic behaviour of this structure. The contextual analysis right now stresses onauxiliary conduct of multi-story working for various arrangement shapes like rectangular shape, H, U, L and plus shape. Demonstrating of 12-stories reinforced concrete frame structure is done on the ETABS programming for analysis. Post analysis of the structure of bending moments, maximum storey displacement and maximum shear force are computed and then compared for all the analysis result cases. For analysis of the structure response spectrum analysis is used. [ABSTRACT FROM AUTHOR]

The article is devoted to the moment method, according to the principles of which it is possible to determine the loads that occur in the thin-walled shell of the orbital vehicle hulls from the action of an internal pressure evenly distributed over the area, normally oriented to the middle surface of the shell. In this case, the load on the shell consists of normal forces (longitudinal and circumferential), the transverse force that causes radial displacements in the shell, and the bending moment in the longitudinal plane of the object. The specified bending moment may occur when inertia forces (for example, the Coriolis force) are manifested when an orbital vehicle moves from one orbit to another in vertical directions normal to the orbit (rotary movements); the same rotary movements may cause inertial forces to occur when maneuvering spacecraft and rocket blocks at the same height (in conditionally horizontal directions). To determine the above-mentioned loads and radial displacements of the shell, a mathematical algorithm is proposed that is based on the principles of the moment method of calculation according to the infinitely long shell scheme, which is typical for orbital vehicles. [ABSTRACT FROM AUTHOR]

Load-deflection curve of an eccentrically loaded pushrod made of Superelastic Shape Memory Alloy (SMA) has been traced by using equilibrium equations. The pushrod is modelled as an eccentrically loaded column with pinned ends. The column material has highly non-linear and non-symmetric response in tension and compression. While solving the governing equations modifications are necessary to the stiffness modulus term at each load step since stresses may exceed proportional limit (since material non-linearity is involved and Hooke's law can't be applied). For various loads, curves of reduced modulus and bending moment against deformation of circular SMA pushrod are evaluated using a computer code written in Octave. Through another computer code in Octave, column's load-deflection curves have been traced continuously for increasing value of the loading parameter. When a distinct change in the mode of deformation is evident in those curves, the column is at a state of unstable equilibrium that leads to its buckling. Corresponding load is said to be column's buckling load. The shape of column is largely deformed because of snap-through type buckling. [ABSTRACT FROM AUTHOR]

The fibre-cement properties are strongly influenced by the type of reinforcement fibres used. Meeting the demanding requirements for fibre-cement products and ensuring their long-term durability requires constant testing of new fibre-cement modifications. In the experiments, a new type of PVA fibres was tested for the production of fibrecement profiled sheets with an emphasis on increasing the quality of the resulting product while maintaining the same economic demands of the whole process. The following parameters of the final product were tested: bending moment, linear load, density and water impermeability. [ABSTRACT FROM AUTHOR]

The contemporary situation shows that the influence of soil structural interface (SSI) might be adverse to the seismic reaction of structure and abandoning soil structural interface in the analysis may lead to a risky strategy. Although this, the customary design procedure usually involves a postulation of the fixed condition at the base of foundation avoiding the flexibility of the base of the structure, the contractibility of soil mass and as a result, the effects of foundation settlement on additional rearrange of bending moment and shear force demands. The effects of SSI are examined for G+15 story vertical irregularity high-rise RC building resting on a raft foundation. Two methods are used to evaluate the target MRF RC building: Equivalent Static Load Method (ESLM), Response Spectrum Method (RCM). To acquire the statistical result by using SSI modal situation are those consistent to fixed-base support condition and the ultimate response of story shear, story displacement, and story drift are analyzed. [ABSTRACT FROM AUTHOR]