Bentley staad.pro v8i

Моделирование расчетной схемы

  • Библиотека элементов для текущего проекта с предварительной установкой жесткостей, степеней свободы, эксцентриситетов используемых впоследствии элементов.
  • Гибкий графический и текстовой ввод данных в диалоговом режиме, с использованием параметризованных библиотек форм и геометрии элементов, в т.ч. поддержка пользовательских VBA-макросов.
  • Прямоугольная и цилиндрическая система координат.
  • Элементы типа балок, идеальных ферм, пластин (мембран и оболочек), связей, гибких нитей, массивов в любой комбинации.
  • Генерация сетки произвольной формы на плоскости любого наклона.
  • Жесткие, шарнирные, пружинные, частично защемленные опоры.
  • Пользовательские видовые окна.
  • Генерация упругого основания под сооружением.
  • Спецификация сечений конструктивных элементов по базам данных стальных профилей, по таблицам пользователя и в параметрической форме.
  • Геометрические характеристики произвольного сечения с использованием SectionWizard.

Dynamic Loads

The solution of a dynamic analysis is dependent on the geometry and a mass matrix.  The mass matrix is defined once and can be:-

  1. A Reference Load Case classed as MASS (see Reference Load Cases above)
  2. Loads included in the first Time History load case
  3. Loads included in the first Response Spectrum load case

Therefore any loads that have been included in a Time History or Response Spectrum load case to determine the mass matrix will be affected in the same way as when used in the regular static loading condition.

Time History.  The definition of a time history forcing function is not affected by any changes by the ISM updates.  However, the forcing functions are assigned to nodes and any modification on nodes, such as deletion would impact this.  As nodes of deleted members are not deleted, the applied loads remain, but it may be that merging the member leaves nodes unconnected to the model which means they would need to be manually reintroduced into the model.

Response Spectrum.  No part of a Response Spectrum definition or application is dependent on the changes that take place during an ISM update.

Action Required:- Check any loaded nodes that may have been disconnected due to deletion or movement of members these may need to be reintroduced into the analysis model

Проектирование

  • Сортаменты стального проката по стандартам США, Канады, Великобритании, Германии, Франции, России и других стран.
  • Подбор и проверка сечений металлических конструкций в соответствии с требованиями норм и кодов проектирования США (AISC, AASHTO0), Германии (DIN 18800 T1), Европы (EC3), России (СНиП II-23−81 — с начала 1997 года) и других стран.
  • Подбор и размещение продольной и поперечной арматуры железобетонных балок, колонн и плит в соответствии с требованиями норм и кодов США (ACI 318−89), Германии (DIN 1045), Европы (EC2), России (СНиП 2.03.01−81 — с начала 1997 года) и других стран.
  • Проектирование фундаментов с помощью STAAD. foundation под колонны, деревянных конструкций по зарубежным нормам US (ACI), UK (BS 8110), Indian (IS 456).
  • Расчет сварных и болтовых соединений.

Member Loads

There are 10 types of member load that can be defined on a STAAD.Pro model.  The STAAD.Pro ISM StructLink module currently automatically manages the following member load definitions during an update:

  • UNI, uniform force
  • UMOM, uniform moment
  • CON, concentrated moment
  • CMOM, concentrated moment
  • LIN, linearly varying
  • TRAP, trapezoidal

Loading of these types on members that are split or merged due to changes in the geometry of the physical model are managed and may be changed to provide an equivalent loading pattern.

Therefore, if a member is split due to the addition of a member or due to the move of a member so that it now interacts with an existing member line, any of the above loads will be positioned on the new set of members.

Action Required:- None

Example

Consider the following model which has loading on members which are affected by a change in the ISM model:

Updated model with cross member deleted, support beams combined:

Add a member that divides existing members:

Analysis model updated:

These other member loads are currently not managed during an update and should be managed by the engineer are less commonly used:

  • TEMPERATURE
  • PRE/POST STRESS
  • FIX END
  • STRAIN

Action Required:- Members that have been subject to these 4 load types should be reviewed and if modified by the update, should have the loading reassigned for the updated geometry.

Floor and Area Loading

STAAD.Pro supports two methods for creating loads on members using a definition of a zone which is used to calculate loads on members.

  • FLOOR, this can create either 1 or 2 way or loading by defining either:-
    • A group of members which are then used to determine closed loops within which the loading is assigned and then a calculation performed to establish the loading to apply to these members.
    • A zone in 3D space and let STAAD.Pro find the members in that space, and use all these members to find closed loops of members in a given plane, then apply loading in that area, establish the loading that then gets assigned to the members of the loops.
  • AREA, this is a legacy command and not a recommended method due to a number of significant limitations in the algorithm.

The update process manages members that are in load groups such that

  1. If a member is removed from the model as it has been deleted, thus is removed from the group definition.
  2. If members are merged into a new member, the resulting member is maintained in the group.
  3. If members are split due to the introduction of a new member, then all the new parts are included in the group.  However, note that the analysis members formed from the new physical members are not considered part of the group.  If this is required, then it should be managed by the engineer.

Action Required:- Where a member is inserted into an area that has been defined as a member group for floor loading and intended as a load bearing member, add into the floor group definition.  Where the volumetric form of the floor load command is used and a whole structure move has been implemented, the definition of the volume should be updated by the engineer to suit the new location of the model.

Совместная работа и открытая архитектура

  • CIS/2.Обмен данными с другими программами стального проектирования.
  • ProSteel.Двунаправленная связь для поддержки создания модели, ее проектирования и получения конструкторской документации.
  • AutoPIPE.Передача данных о конструкции стальных опор из STAAD.Pro в AutoPIPE для моделирования реальной жесткости трубопроводных опор. Обратный импорт реакций опор для проверочного расчета строительных конструкций.
  • STAAD.foundation.Импорт из STAAD.Pro реакций опор и позиций колонн для проектирования фундаментов.
  • OpenSTAAD.Полнофункциональный прикладной интерфейс (API) позволяет создавать свои приложения и макросы с использованием языков программирования: VB, C++, C#. С помощью OpenSTAAD данные о расчетной схеме и результаты расчета можно передавать в такие программы, как MS Word, MS Excel, MathCAD и свои собственные приложения. STAAD.Pro имеет встроенный редактор VB макросов.
  • CAD, DXF.Использование CAD модели как основы для получения каркаса конструкции, как структурную сетку или внешние границы сборной плиты, предназначенных для генерации сетки конечных элементов. Компанией Structural Integrators, являющейся одной из партнеров компании Autodesk, разработан интерфейс SI Xchange между Autodesk Revit Structure и STAAD.Pro. Возможности SI Xchange обеспечивают бесшовную связь между эти программами. Пользователи Autodesk Revit Structure имеют возможность передачи расчетной схемы в STAAD.Pro для выполнения расчета и возврата изменений в конструкции после расчета из STAAD.Pro в Autodesk Revit Structure, обеспечивая тем самым сокращение времени на проектирование и исключение ошибок в проекте.

Wind Load

Wind loads are defined in 2 parts, the definition of the wind, typically in terms of intensity over height, and then the inclusion of this in a load case.  The actual resolution of the loading onto the members is done at analysis time; hence changes in the model due to ISM update do not affect the result.

There is one area where a modification by ISM can impact on a wind analysis.  Part of the definition can be an EXPOSURE parameter; this is intended to allow local reductions (on increase) in forces due to the wind at specific nodes on the model.  If the nodes are modified/removed, these definitions will need to be reviewed.  This has to be a manual procedure.

Additionally, the extent of the structure subject to wind loading can be constrained by a number of dimensions in the global axes.  If the model has been modified with a global move, then this will need to be modified.

Action Required:- Check nodes that have been removed or added to ensure if they need to be included/removed from the exposure list.

Node Loads

Nodes are always retained, thus node loads are also retained.  However, it may be that during the update, removal of members can leave nodes isolated from the main structure and will need to be manually re-located back on the structure. 

Recommendation, it may be better to use member concentrated loading instead of node loads so that it is clear what the intension of a load at a point which is a junction of several members so that if a member is moved, the load can move with the appropriate member.

Action Required:- Check for isolated nodes using the menu item ‘Tools>Check Orphan Nodes’ and convert to member loads

Snow Loading

Snow loading is defined in 2 parts, a definition which is generic and not affected by the structure and an assignment in a load case in which the zone in which it is applied is defined by a FLOOR GROUP.  Hence the issue of floor loading defined above (i.e. groups that have members split with the introduction of new members not getting added to the GROUP) will impact on the snow loading.

Action Required:- Where a member is inserted into an area that has been defined as a member group for snow loading and intended as a load bearing member, add it into the floor group definition. 

Summary

The main loading types are automatically updated, but it is still prudent to review all the loading after an update to ensure that the loading on the updated geometry adequately reflects the specific engineering requirements for the analysis that is to be performed.

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