In AMECO-17 system the entire analysis-design process is computerized through a common data base with geometry, loading generation, structural analysis, members size selection, graphics and construction costing being integrated into a continuous cyclic operation.



Any changes in the member sizes from this cyclic process automatically invoke re-analysis of the structure in whole or in part. However, this requires relatively little computer resources since the structural analysis is performed only on the affected portion of the structure with a type of joint relaxation methodology rather than by resolving the global stiffness matrix of the entire building in the displacement method.

Member design is a building code dependent process with either WSD, USD, ASD, LSD and Plastic and Ductile methods – all available in AMECO-17. English and SI system of units are available. Beams, columns, slabs, shear walls, trusses, bracing and composite members are all accommodated in two or three dimensional structures.

This AMECO-17 integrated process provides an environment for designing an entire building as whole 3-D unit subjected to gravity dead/ live loads, wind and earthquakes motions. This applies to steel and concrete buildings of any size. Substantial saving in engineering time – 75% or more are realized.

INTEGRATION OF DESIGN PROCESS

In the AMECO-17 system, the entire design process has been computerized and integrated. The process is divided into six operations:

1. Geometry generation
   
   
2. Loading generation
   
   
3. Structural Analysis
   
   
4. Member design
   
   
5. Geometry/ loading update
   
   
6. Graphics
   
   

All these operations are integrated into a continuous cyclical process and therefore share a common data base. This cycling is repeated until the engineer’s criteria is satisfied.

During the first cycle, operations 1 to 5 are performed on the entire structure. During successive cycles the operations are only carried out on the part of the structure that is affected by the changes in member sizes. Thus, the required computer time reduces with each design cycle.

Command Language Input

To make AMECO-17 attractive to the practicing engineer every effort has been made to simplify and minimize the input data. A special command language has been developed, incorporating structural terminology. These commands are used to generate the geometry, loading and control the automated analysis-design process and to display selective design documents and graphical displays of the structure.

Graphical displays can be produced during the input phase and after the design is completed.

Without exception, AMECO-17 input data is at least ten times less in volume than the required for any other structural design program.

Loading Generation

All necessary operations associated with loading are performed by AMECO-17. The engineer specifies the following loading parameters:

• floor and snow loads per unit area (kPa, psf)
  
  
• wind pressure per unit area of walls
  
  
• earthquake zone for static seismic forces
  
  
• response spectra for dynamic seismic forces
  
  

AMECO-17 then computes all the member dead loads; revises those as the sizes change; models and computes floor loads on beams, slabs, joists and trusses; computes the mass of the structure, as well as the wind and seismic forces and their eccentricities.

Non-structural loads such as mechanical equipment are input by the engineer as concentrated or uniform loads.

AMECO-17 generates as many live load cases as there are beams and slabs in the structure.

Critical loading combinations for gravity/lateral loads, including settlements, are generated by AMECO-17 in accordance with the engineer’s specified code. This includes computation of live load reduction, impact for vehicles loads, CQC, RSS modal forces.

Construction Simulation by Segmental Analysis

For multistorey buildings, the construction sequence is simulated. At each stage of construction (as a new floor is added), the structure is analyzed up to the erected level only. As the erection proceeds level by level, the new member dead load effects are added to the stresses of previous construction stage.

In taller building designs, ignoring the construction sequence effects can lead to Substantial errors.

STRUCTURAL ANALYSIS

First and second order static and dynamic analysis are performed by a joint relaxation technique. Subjected to external loads, the structure is maintained in state of motion as the forces propagate from joint to joint in three dimensions, until statical equilibrium is achieved or instability encountered. Individual member stiffnesses are only used in this propagation process, thus bypassing the setting and solving simultaneous equation matrixes, used in most structural analysis programs.

The end result of the propagation process consist of joint rotations and translation in the three orthogonal directions, from which the first and second order moments and forces are calculated for each member of the structure

Types of Analysis

Five types of analysis are available in AMECO-17:

1. Approximate analysis – to determine member sizes
   
   
2. Linear elastic analysis
   
   
3. Nonlinear elastic analysis – includes P-delta effect, member cracking, axial-flexural interaction
   
   
4. Segmental analysis – to simulate construction sequence
   
   
5. Dynamic response spectrum analysis
   
   

In the fully automatic design mode all five types of analysis are carried out. However, during the first design cycle the nonlinear analysis is suppressed, while in successive cycles, the approximate analysis and linear analysis are no longer executed.

Member Stiffness Formulation

The member stiffness formulation include flexural, shear and axial distortions. Each member is considered as a non-prismatic member with rigid or deformable links at ends, and with, elastic connections if so specified. The column flexural stiffness are modified as function of axial load and the reinforcement ratio in the case of concrete columns.

Integation of Structural Analysis and Member Design

In the cyclical design process, any change in member sizes necessitate re-analysis of the structure in whole or in part. AMECO-17 , this accomplished very efficiently. First, the analysis is started of the "previous" structure. Thus only the joints connected to the revised members are subjected to new unbalance forces. And secondly , the analysis is extended only to the affected part of the structure.

For gravity load cases, such as live loads on beams or slabs, the forces do not propagate very far from the applied load. Thus thousands of loading cases and hundreds of revisions to member sizes can be accommodated for any size of structure – an impossible task for matrix programs.

For larger structures, the AMECO-17 structural analysis speed is at least 500 times faster than the speed of matrix programs.. Further more the AMECO-17 second order analysis is executed at practically the same speed as the first order.

MEMBER DESIGN

The structural engineer makes decisions based on science, art, intuition and experience and in effect, uses so called "engineering judgement". Some of the decision taken by the engineer are important, such as selection of structural system.. However , most of the engineer’s time is spent on arriving at decisions of less importance such as member size selection or choosing reinforcing bar diameter.

To relieve the engineer of this routine but necessary part of design , AMECO17 has many built-in design decision routines. Examples are: minimum and maximum width and depth of a member, rebar arrangements, sizes, type of stirrups, splice location for columns and truss chords.

The engineer has the option to supplement this built-in AMECO-17 criteria to meet his own requirements, such as minimum size of members

Steel Structures

Steel structures can have members with rigid, elastic or pinned and deformable joints.

• Beams
  
  
• Composite beams , six types
  
  
• Trusses, joists
  
  
• Columns
  
  
• Bracing
  
  
• Shear walls
  
  

Automated design is incorporated in AMECO-17 for all above types of members. Four design methods are available: LSD, ASD, WSD and plastic. The design operations performed include member size selection, stress or capacity checking, deflections, column doubler plate selection, shear stud design, all in accordance with the American AISC standard and Canadian NBC building code.

Concrete Structures

Concrete structures may consist of the following types of members:

• Flat plate, flat slabs
  
  
• Waffle slabs, joist slabs
  
  
• Voided slabs
  
  
• Beams with rectangular, ‘L’ or ‘T’ cross-section
  
  
• Slabs, one-way
  
  
• Columns with capitals
  
  
• Shear walls with pilasters
  
  

Automated design is incorporated in AMECO-17 for all the above types of members. This includes member proportioning; capacity or stress checking; short and long term deflection calculations; axial, flexural, shear reinforcement selection and reinforcing bar schedules.

The design is performed in accordance with the ACI-318 standard and the NBC of Canada building code along with few other building codes, using LSD, USD or WSD methods with ductile provisions. The members can be reinforced with SI, American or Metric series of bars.

GRAPHICS

The AMECO-17 graphics module produces visual displays of the structure of varying complexities – ranging from single line diagrams to framing plans and elevations, approaching contract drawing quality. The structure can be of steel or concrete.

This module is totally integrated in the analysis-design process with all the structural data necessary for the graphics displays residing in the data base.

Graphics displays can be produced during the input phase and after the design phase.

During the input data preparation phase, "Ctrl-Q" produces an instant graphical display of the floor plan just entered. This enables the engineer to verify his input commands, before proceeding to the next floor level. By specifying the level number , any other floor can be displayed

After the design phase, framing plans and elevations of various complexities are produced with the PLOT or DAW commands, which are entered in the input data. In these commands the engineer specifies the type of information to be displayed, e.g. member sizes, building grid lines, drawing size and scale.

RESULT REPORTS – DESIGN DOCUMENTS

The design reports are as detailed or as concise as the engineer desires. The reports are in Rich format and in colour.

• Static analysis results
  
  
• Dynamic analysis results
  
  
• Design tables for members
  
  
• Reinforcing schedules for concrete members
  
  
• List of structural profiles for steel structures
  
  
• Bill of materials
  
  
• Construction costs
  
  

The above reports can be accessed by the engineer one at a time.

AMECO-17 TRACK RECORD

The AMECO-17 track record includes billions of dollars of construction throughout the world: Canada, United States, Australia, Mexico, Chile, Congo, Iraq, Kuwait, Senegal, Egypt, Saudi Arabia, Indonesia and others.

AMECO-17 designs an entire building structure as a whole three- dimensional unit, for gravity and lateral loads. This produces higher accuracy, more safer structures and substantial reduction in engineering design time – 75% or more.

The following are typical classes of structures AMECO-17 has been used to design – in steel and concrete:

• tall buildings: hotels, offices
  
  
• high-rise and mid-rise buildings: hotels, condominiums, offices
  
  
• low-rise structures: condominiums, aircraft hangars, museums, wharfs
  
  
• heavy industry: power plants, steel mills, pulp and paper mills
  
  

AMECO-17 designs an entire building, as a whole three- dimensional unit, for gravity and lateral loads. This produces higher accuracy, more safer structures and substantial reduction in engineering design time. It is equally applicable to a 70 storey hotel and a four level paper mill.