Program Altoqi Eberick PDF

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Summary

The Computational AltoQi Eberick program is intended for design of reinforced concrete buildings. It has a powerful data entry graphics system, coupled with the analysis of the structure in a space frame model and the various design features and detailing of elements. These are slabs, beams, columns...

Description

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5 PROGRAM ALTOQI EBERICK

5.1 INTRODUCTION

The Computational AltoQi Eberick program is intended for design of reinforced concrete buildings. It has a powerful data entry graphics system, coupled with the analysis of the structure in a space frame model and the various design features and detailing of elements. These are slabs, beams, columns, pile caps and shoes. It stands out for its productivity in the preparation of projects and the study of different solutions for the same project. The structure of the building is defined by floor, representing the different existing levels in architectural design. The launch of the elements is done graphically, directly on the architectural plan, allowing you to define different assumptions in the calculation of the model. The program allows viewing of the complete 3D structure (Figure 22) and the results are supplied through window scaling shaped sheet. Details of the elements follows the usual practices of the Brazilian market and can be organized into boards for later plotting, EBERICK MANUAL (2003).

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FIGURE 22 - Project seen in perspective generated by Eberick program. Source: Private author

5.2 KEY FEATURES

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graphical data entry in integrated CAD environment with the possibility of architecture import DXF format;

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three-dimensional visualization of the structure;

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analysis of the structure in space frame model with verification of global stability;

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possibility of shaping the connections between the elements (bearings, recesses, semi-rigid connections);

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ability to analyze the panels slabs on a flat grid model with semi-automatic discretization;

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sizing of the elements according to NBR-6118 standard (2003);

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detailing the elements with the possibility of editing hardware and updating the steel ratio;

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generation of bills of materials by element, board, deck or project;

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generation of several diagrams, presenting reactions of slabs and beams, arrows floors, among others;

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reporting graphically formatted;

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generation configurable format boards distributing recitations.

The Eberick is a computer system in Windows environment to aid the design of building structures of multi-storey reinforced concrete. The use of a computer program in real situations involves structural design on a lot of responsibility and experience for the user. This system should be used only by trained and competent professionals, just as a tool to the project and not as a closed solution. No computer program, however sophisticated it may be, is able to fully replace the work, the considerations and the judgment of the engineer. This program and the computer does not have intelligence, with responsibility for the correct design of the structure assumed by the user, which must check all input data and the results presented by the program. For proper use of the system, the user must make a previous trial in order to ascertain whether the structure that will design for your building can be analyzed by the model used by the program, with all its restrictions, getting to the user charge all calculations, checks and details of additional armor, which are required to complement the project. The results are directly dependent on the data entered by the user, so incorrect input data will invariably produce erroneous results.

5.3 PROGRAM CALCULATION MODEL EBERICK

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Systematic in which the system is based is to model the structure through a space frame composed of beams and pillars of the building. In this case, the elements are represented by bars connected to each other by us. Each pillar and each beam section are composed of gantry bars, which are obtained the internal forces for the design. slabs panels are calculated independently of gantry shape.

The calculation of the structure is done as follows:

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slabs panels are calculated and assembled according to the process that is set;

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The reactions of the slabs are transmitted to the beams where they are based;

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It is assembled space frame of the structure receiving the load calculated by the slabs;

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The porch is processed and the internal forces are used for detailing of structural elements.

The program uses the displacement method or the stiffness matrix method to make the Direct structural analysis. From this method, we determine the effects of actions in the structure so that they can be made checks of ultimate limit states and the states limit the use. The analysis results are basically the nodal displacements, internal efforts and responses in support links.

5.3.1 Direct Matrix Method Stiffness

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The Eberick program calculates the rigidities of the elements using the matrix analysis (method of displacements). The method of displacements, also known as rigidity method is a method of analysis of reticulated structures using the rigidity of the elements to form a system of equations relating to the displacement loads acting on the structure. The basic equation is the method:

{ F }=[ K ]⋅{ d }

Where F {} is a column matrix (vector) of the external loads, [K] is the stiffness matrix of the structure and {d} is the column matrix of offsets.

For a given set of external loads, the system of equations is solved by calculating the displacements. Efforts in the structure of the bars are obtained on the basis of the displacement and the stiffness matrices of each individual element. The method of rigidity is a general method which can be applied to solving any kind of lattice structure. The analysis of a structure by the method stiffness can be described by the following steps, as manages and Weaver (1980):

1. The description of the structure includes its type, the location of the nodes, positions the bars and the location and types of support; 2. Specification types of deformation to be considered in the analysis, such as deformations by bending and axial deformations. Depending on the types of deformations to be considered should be given to the appropriate rigidities bars;

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3. Determination of the number of nodes shifts unknown or degrees of freedom in the structure. It is necessary to provide a corresponding number of artificial linkages to produce constrained structure in which all nodes are null offsets; 4. Analysis of the restricted structure subjected to loads. All charges, except those corresponding to an unknown node displacement, are considered to be applied to the fixed structure and evaluated the various actions in the structure. The most important actions to be determined are the actions that correspond to the unknown displacements. Other actions are of interest to the end members and the reactions at the supports; 5. Analysis structure constrained by other causes; 6. Analysis restricted to the structure unit of displacement values; 7. Determination of displacement. The superposition equation for shares corresponding to shifts in the real structure is:

{ F } − {F 0 } =[ K ]⋅{ d }

In this equation, the vector {F0} includes the effects of loads, temperature fluctuations, initial deformation and displacement of support: Where {F} are the efforts on us, {F0} are the immobilization efforts of us, due to loads applied in bars. When the overlap is solved equation as a function of displacement, the result is: −1

{ d} = [K ] ⋅( {F }− { F 0})

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8. Determination of end actions and reactions. Vectors for the end member of actions and reactions, respectively, are obtained in the actual structure of the following overlapping equation:

{ S} − {S 0 }= [ r ]⋅{d }

When the vectors {S}, {S0} and {d} are obtained, the analysis can be considered completed.

5.3.2 Considerations Calculation Program

The structure of the equilibrium conditions (for the model with undisturbed geometry) must be guaranteed by the user, since the system does not generate solution for hypostatic structures. The Eberick runs to model a linear static analysis of the first order, which means:

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The system does not take into account variables actions over time, due to vibrations, earthquakes, etc.

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The system analyzes a single charge hypothesis and are therefore restricted to cases in which the alternation of variable loads can be considered negligible. Generally, this occurs in buildings in which the variable loads represent maximum 20% of the total building load.

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The system assumes that the materials have linear elastic physical behavior for all points of the structure, that is, it assumes that at no point are exceeded the limits of proportionality of the material stresses in service.

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The system does not take into account the change in structure due to the actions in determining the results of displacements and efforts. The displacements obtained in the first calculation, from the actions modify the initial geometry of the structure. The effect of actions that remain working in this deformed structure, would again change all internal efforts, including the offsets. This effect is known as the effect of 2nd order, if they happen variations of over 10% in the values of internal forces this effect becomes important and should not be neglected. In these cases, the interaction between normal loads and bending moments can be important.

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For the deformed structure model, balance should be checked for stability overall process to assess the effects of second order, which may arise in the structure due to horizontal displacements significantly change the internal stresses. The verification process used by Eberick is simplified based on the NBR 6118 (2003). Made the considerations was initiated the launch of the program structure

in accordance with the manual model. It should be noted that the principle adopted the pre-estabelecidade setup by the program itself. One of the unique settings that have changed, referred to the wind efforts, which are not considered in this work and therefore were removed from processing. In the same way that manual release, we used the same values of loads on the beams, and accidental loads coatings. The structure was processed as space

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frame and all connections (bindings) between the elements considered to be rigid, ie, transmission of bending moments....