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In this paper comparison of shear force and bending moment of T beam deck slab having longitudinal girder and cross girder is done using courbon's method (manual analysis) and grillage model (using staad pro). Construction stage wise grillage model is prepared in staad pro. Bridge having carriage widths of 7.5 m have two types of live load as per IRC 6 i.e. Class 70R (W) and Class A-2 lanes. Static check of grillage model is compared with manual calculation having 0% difference. For dead load, shear force and bending moment of girder difference using manual calculation and grillage model comes out to be 0.64% and 2%. In manual calculation the reaction factor of an individual girder is calculated using courbon's method and multiplied with maximum bending moment. In live load calculation, for Class 70R (W), difference in bending moment for girder A, girder B and girder C comes out to be 26.45%, 4.78% and 28.66% but total moment difference is 0.05% while for Class A-2 lanes), difference in bending moment for girder A, girder B and girder C comes out to be 21.57%, 9.92% and 16.53% but total moment difference is 0.7%. So, from the result it can be seen that the total design moment of the girder comes out to be nearer using both the method while the girder wise difference in bending moment is found to be higher for outer girder and lower for inner girder. [ABSTRACT FROM AUTHOR]

This paper considers the application of the limit equilibrium method to the calculation of a double hinged circular arch loaded with a uniformly distributed vertical load. It is assumed that the arch has a rectangular cross-section made of a homogeneous elastic plastic material with different tensile and compressive yield strengths. The peculiarity of the limit state calculation is that the section works elastically until the transition to a plastic state of the entire section. If the action of the longitudinal force is not taken into account, in the limiting state a classical plastic joint is formed in the cross-section, which allows unlimited rotation relative to each other of the sections located infinitely close to the plastic joint. If the bending moment and the longitudinal force are taken into account simultaneously in the limit state, the possibility of unlimited rotation and unlimited linear displacement of the sections located infinitely close to the origin of the plasticity arises. In order to calculate the limit load for an arch, it is first necessary to obtain a dependence describing the strength area of the cross-section. This dependence relates the ultimate moment and ultimate longitudinal force for the section and is often referred to as the yield stress condition. In this paper the yield stress conditions for rectangular sections of arches with constant and variable stiffness are presented. Using yield conditions of the section and equations of balance of the arch it is possible to construct and solve an optimization problem for finding the minimum load which satisfies both equilibrium and yield equations. Thus, the target function of the problem is the value of ultimate load and the design variable is the coordinate of section which goes into the plastic stage. This problem was solved by means of spreadsheets. Also non-linear calculations of arches with constant and variable stiffness were performed in PC Lira-SAPR. Comparison of the calculation results showed their satisfactory convergence. [ABSTRACT FROM AUTHOR]

Bridge construction design on this design used a prestressed PCI concrete I-Girder. The span of bridge was 40 m which is consist of 3 spans with total length for 120 m. The calculation of the analysis for the structure depends on the structural type. For this design, the bridge was assumed to be indeterminate static which the bridge reactions are more than 3. The internal forces of I-Girder consist of shear forces and bending moment which can be get by simulate the bridges loading that related to the bridge structure. The software for designing the bridge structures and obtained the internal forces value are using SAP 2000 software and manual calculation method. The internal forces data was obtained by calculating the girder structure using manual calculation and analyze using SAP2000 software and be compared by the values. The internal forces is taken at 20 m, 30 m, and 40 m span of girder to be compared the difference value of manual calculation and software analysis using regression line. [ABSTRACT FROM AUTHOR]

The use of shotcrete in tunnels is common. Durability is one of its most essential qualities. Application speed, cost-effectiveness, and socioeconomic considerations are all important factors to consider. The space here between façade of the trench and the shotcrete lining, the velocity of excavation, and other factors must be noted in the tunnel that has already been excavated. The ideal shotCrete thickness for these models was determined using axial force and bending moment interaction plots for different short depths. The findings of this inquiry, and also the method used, may be applied to the design of mining canal supports and civil engineering tunnels of various sorts. [ABSTRACT FROM AUTHOR]

In view of the active development of computer-aided computing technologies with software tools for a wide range of engineering tasks, it becomes urgent to choose reasonable and proven methods of calculation that take into account the specific nature of the structure, and comparisons of results. The article considers the features and results of the calculation of the sheet piled quay wall (anchored bulkhead with one level of land tie), obtained using two commonly used specialised programs (CAD Hydrotechnika and PLAXIS 2D) as well as graphically using the example of the refurbished wharf. The main parameters analysed were maximum bending moments and force in the anchor traction. The analysis of the results showed that there was a significant variation in the values of the main parameters, which indicated that more research was needed to identify the reasons for the discrepancy and, if necessary, to correct the calculation methods and algorithms and to verify them. [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]

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]

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]

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]

This paper deals with the problem of the sensitivity of strain gauge force sensors to bending moment which badly affects the measurement accuracy. The bending moment sensitivity can be caused by incorrect force sensor geometry, suboptimal arrangement of strain gauges, imprecise positioning of strain gauges during installation, variation of the strain gauges’ properties. In this study we investigate the effects of the strain gauges’ positioning errors and variation of their properties on the bending moment sensitivity for the case of a compression membrane force sensor having axis-symmetrical geometry. Firstly, we obtain the information about the sensor’s stress-strain state when it is loaded with compressive force and bending moment using Finite Element Analysis. The Finite Element Analysis results are used in conjunction with probabilistic modelling techniques for evaluation of the distribution of the bending moment sensitivity. The modelling results have shown that the distribution’s mean value is approximately zero due to the axis-symmetrical geometry of the force sensor. The standard deviation of the bending moment sensitivity depends on the number of strain gauges in the Wheatstone bridge and the gradient of the strain caused by bending moment in the areas where the strain gauges are installed. The proposed method of evaluating bending moment sensitivity can be applied to other kinds of parasitic loads and other types of strain gauge force sensors for minimizing the sensitivity to parasitic loads in single- and multi-axis strain gauge force sensors. [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]