MasterKey Wind Loading to BS 6399

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<ul><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 1/31</p><p>MasterKey Wind Loading to BS 6399 20-1</p><p>6 MasterKey Wind Loading to BS 6399 Pt2</p><p>6.1 Introduction</p><p>You can use MasterKey Wind Analysisto quickly and accurately determinewind pressures for any site in Great Britain, using the built-in O.S. location mapor by entering a grid reference. You have a choice of several wind analysismethods with which to refine the wind pressures for your particular site. For theuse of the MasterKey Wind Analysis program as a stand-alone module referexclusively to section 2 in this manual.</p><p>MasterKey Wind Analysis on its own gives you only a fraction of the power of thecomplete system. For you to reap the full benefits, MasterKey Wind Analysisintegrates with the 3D Model Managerto give you the most powerful tools</p><p>available for automatically applying wind loads to any structure. For the use ofMasterKey Wind Analysis with the 3D Model Manager refer to section 3 in thismanual.</p><p>The good news for users throughout Ireland and countries elsewhere in the worldis that you too can unleash the potential of the integrated system. All you need todo is enter the relevant site information and basic wind speed in the MasterKeyWind Analysis to evaluate the wind pressures and then use the integratedsystem to apply the wind loadings to your building.</p><p>6.1.1 MasterKey Wind Analysis</p><p>First we will look at the MasterKey Wind Analysis interface and understand howto use it, before examining how it integrates with the 3D Model Manager andMasterFrame.</p><p>Select the MasterKey Wind Loading to BS 6399 from the Designer Suite menu.</p><p>6.1.2 Choosing a Site Location from the Wind Data Map</p><p>A location is chosen from the MasterKey Wind Analysis site data map or ifoutside Great Britain, a default site can be set up to generate the wind pressuresfor a particular location. Pick a site directly off the map or enter the site gridreferences, if known, to get exact site information. (Note - grid references can beobtained from various internet sites, for example, www. multimap.com, based onthe site address or post code.)</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 2/31</p><p>MasterKey Wind Loading to BS 6399 20-2</p><p>Accurate wind and topographical information is contained within the Wind Mapdatabase. This information is used by the program to obtain the wind pressureson a structure as it varies with height and orientation. Several wind diagonallengths can be taken into account. The user can choose which analysis method</p><p>to employ.</p><p>Typical Wind Loading screen (linked to 3D Model Manager)</p><p>The Town/Country, Topographical and Categories maps are displayed at the topright of the screen. Below these, the town/country/sea distances for the localarea and the wind pressure distribution for the site, varying with height, are</p><p>displayed. All the site data and wind pressures are shown in the calculations areaon the left of the screen.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 3/31</p><p>MasterKey Wind Loading to BS 6399 20-3</p><p>6.1.3 Site Data interface</p><p>The Site Data tab enables you to enter a title for each brief, add and sort briefsand select which map type to be the main graphic. The grid references areshown here and can be manually changed if you know the exact grid references</p><p>for your particular site. The basic wind speed and site altitude are given. Thedata for a particular site can be saved as an independent file for future re-loading(Save/Load Site for BREVe2). If the site is outside Great Britain, you can set up afile containing a default (overseas) site, using the Set Default Site button. Thesite information for an overseas site is entered in the following tabs, so that thewind pressures can be accurately calculated.</p><p>When used with the 3D Model Manager, the SiteData tab also allows you to specify the orientation ofyour building relative to the North, so as to ensureaccurate application of the wind loading to theindividual faces of the structure.</p><p>6.1.4 Obstructions interface</p><p>If there are obstructions in the vicinity of the structure being examined, these canbe taken into account by specifying the height of and distance to the obstructionsat intervals of 30 degrees around the building.</p><p>If the orientation of the building is known, the UK Sd factors can be used toreduce the wind pressures around the building. If the orientation is not known oris outside the UK, the Sd factors should be set equal to 1.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 4/31</p><p>MasterKey Wind Loading to BS 6399 20-4</p><p>6.1.5 Sea/Country/Town interface</p><p>Fetch distances and category types are automatically included when a site isselected from the Great Britain map. For a site outside Great Britain, the valuescan be entered manually for each orientation.</p><p>6.1.6 Topography interface</p><p>The local topography can be taken into account resulting in modification of thewind loading. This can be done using the internal data within the wind map or</p><p>altered manually.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 5/31</p><p>MasterKey Wind Loading to BS 6399 20-5</p><p>Alternatively, a previously saved file (*.Shf) can be used to bring the localtopography data into account, or</p><p> the user can set their own data for a site.</p><p>There is also an option to use the site altitude only to evaluate the wind loadingignoring the effects of local topography.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 6/31</p><p>MasterKey Wind Loading to BS 6399 20-6</p><p>6.1.7 Report (Output) interface</p><p>On the Report (output) tab, the user can select which method to employ for thecalculation of the wind loads Standard, Hybrid, Directional or Designers Guide.Having settled on the appropriate method, the screen and printing output options</p><p>can be selected. The basic wind speed automatically selected from the map maybe changed if desired, as can the start and length of the season underconsideration. Building floor levels and wind diagonal lengths can be changedfrom the defaults if necessary (note when used in conjunction with the 3DModel Manager, these values are automatically taken from the model). Select therisk period from the droplist. Finally the graphics scale and number of segmentscan be varied. The wind pressure diagram can be viewed for each wind diagonallength a.</p><p>6.1.8 Printing Results</p><p>MasterKey Wind Analysis results can be printed to a printer or PDF file orexported to Word (PowerPad users) using the Print and PowerPad facilities inthe top menu or the buttons described below:-</p><p>Ensure graphics are always on top.</p><p>Switch graphics on or off when exporting or printing.</p><p>Edit project title and job references.</p><p>Print current or all briefs to printer.</p><p>Export current or all briefs to Word (PowerPad users only).</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 7/31</p><p>MasterKey Wind Loading to BS 6399 20-7</p><p>6.1.9 Viewing of Local Category Map and Wind Pressures Diagram</p><p>The local category map and wind pressure diagram can be manipulated usingthe following buttons from the top menu:-</p><p>3D view</p><p>Front view</p><p>Side view</p><p>Plan view (north)</p><p>Elevation</p><p>Place on plan</p><p>Shade wind pressure diagram</p><p>Rotate diagrams</p><p>Alter vertical scale of windpressure diagram</p><p>6.1.10 File Management</p><p>Files and briefs can be managed using the options from the File and Editing</p><p>menus or using the following buttons from the top menu:-</p><p>Open a new file</p><p>Open an existing file</p><p>Save current file</p><p>Delete current brief</p><p>Copy current brief toclipboard</p><p>Add new brief from clipboard</p><p>Add new brief</p><p>Next or Previous brief</p><p>6.1.11 Additional Help on the BreVe2 Wind Loading</p><p>Help can also be found in the BreVe2 Help system, which will have been loadedwhen the Wind Loading module was added to your MasterSeries programs. Toaccess the BreVe2 help, go to Start&gt;Programs&gt;BreVe2&gt;BreVe2 Help andsearch for the required information.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 8/31</p><p>MasterKey Wind Loading to BS 6399 20-8</p><p>6.2 MasterKey Wind Loading + 3D Model Manager</p><p>MasterKey Wind Analysisintegrates with the 3D Model Managerto give youthe most powerful tools available for automatically applying accurate wind loads</p><p>to any structure, saving you time and effort.</p><p>The MasterKey Wind Analysis automatically calculates and applies the weightedexternal pressure coefficient Cpe to be used with each wind loaded member foreach wind direction.</p><p>The value of Cpe is dependent on the wind surface angle to the horizontal , the</p><p>angle between the wind direction and the normal to the wind surface and thewind zone depending on the position of the member within the wind surface andthe building as a whole, the wind zones are:</p><p> A-D and H-K for walls and inclined walls</p><p> A-G and X-Y for flat roofs, and</p><p> A-J and K-S for monopitch and duopitch roofs.</p><p>Wall Zones Flat Roof Zones</p><p>Duopitch Roof Zones (including roof angle)</p><p>Adjustments are automatically made for corner angles , funnelling effects 0.25bto 1.00b, re-entrant corners and both narrow and wide recesses (introducingzone c1 in the wedge).</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 9/31</p><p>MasterKey Wind Loading to BS 6399 20-9</p><p>The program will dynamically change all Cpe values for any changes you make</p><p>to wind directions at any time. All angular values including , and and allmember zoning locations are dynamically determined by the program. To ensuremaximum flexibility you will however be able to overwrite some or all of thesevalues.</p><p>The method of application can be clearly explained by the following steps.</p><p>Step 1 - Turn on the Use MasterKey Wind Loading option.Step 2 - Specify the wind diagonals (a values) for different members in the</p><p>structure.Step 3 - Specify internal pressure coefficients and internal suction coefficients</p><p>for each wind direction if necessary, e.g. in cases of dominantopenings</p><p>Step 4 - Specify the Wind Directions you wish to consider on the structureStep 5 - Create the Wind Loading cases using the automatic generation tools</p><p>Step 6 - Enter the MasterKey Wind Analysis program to determine the windpressure values for the specified wind directions, wind diagonals andheights of the structure.</p><p>Step 7 - Define the Wind Panels in the structure using the 3D Model ManagerWind Area Loading tools. In this step the coefficients of externalpressure for each wind direction are automatically determined foreach wind panel.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 10/31</p><p>MasterKey Wind Loading to BS 6399 20-10</p><p>Activating the Integration of 3D Model Manager and MasterKey WindLoading</p><p>To activate the integration between MasterKey Wind Loading and the 3D ModelManager,</p><p>1. Select 3D-Model&gt; Area Loading Defaults</p><p>2. Click on the Use MasterKey Wind Loading button.3. Click on the X at the top right of the Titles and Load Combinations to</p><p>close this area.</p><p>6.2.1 Wind Diagonals</p><p>Begin by selecting the Wind Loading option from either the Multi-Storeyor 3D-Modelmenus.</p><p>BS 6399 Pt 2 (cl. 2.1.3.4) makes use of a size effect factor Ca for the</p><p>determination of the wind pressure values. This has the effect of designing ofmembers which are locally loaded by wind (such as cladding members) for alarger wind pressure than members which are globally loaded by wind, e.g.vertical bracing members. Set up the wind diagonals for the individual members(defaults to 5m) and for the bracing systems e.g., 30m representing the windloading coming onto the various bracing systems.</p><p>Select the wind diagonals button to move to thearea of the program where the diagonals and theirrelating members can be defined.</p><p>All members will default to the 5m wind diagonallength unless placed into a new wind diagonaldefinition. For example, create a new definition</p><p>using the button, giving it a relevant title. Insertthe Current Wind Diagonal length and then selectthe members which have this wind diagonal length.</p><p>Tip use the member viewing options in the topright to select, say, the inclined (I) members only.You can then box around these members to addthem to this diagonal group. Switch back to All (A)members to see the full frame.</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 11/31</p><p>MasterKey Wind Loading to BS 6399 20-11</p><p>Note The definition of wind diagonals will result in a more efficient design,however because the program defaults to a conservative value of 5m, specificdiagonal definitions are not absolutely necessary. If you do wish to specify winddiagonal values, then it is recommended to keep the number of additional</p><p>diagonals to a minimum since each diagonal value will have its own set of windloading cases. Hence if many wind diagonals are defined, the number of loadingcases would become very large, resulting in a much increased analysis time. Formany circumstances it would be adequate to have only two diagonal values, i.e.the 5m default diagonal and one larger diagonal value to cover all members thatwill attract force due to wind load but are not locally wind loaded. The additionallarger value should be the lowest diagonal of these types of members.</p><p>6.2.2 Setting up Wind Loading Directions</p><p>Select the button at the top right of the screen to access the area where the</p><p>wind directions are specified.</p><p>Up to 8 wind directions on the frame can be considered using the load groupsW1 to W8. The direction of the wind is defined based on the angle with theframes global X axis. In the example below W1 to W4 is used define fourprinciple wind directions. The angle between the frame Z axis and magneticNorth is specified in the Angle to North text box. If the Draw Global Axis icon isturned on from the top tool bar, then the global axis symbol at the bottom left of</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 12/31</p><p>MasterKey Wind Loading to BS 6399 20-12</p><p>the screen graphically indicates the North direction in relation to the frame globalaxis.</p><p>6.2.3 Defining Internal Pressure/Suction Coefficients</p><p>The internal pressure/suction coefficients are defined in the same table as thewind directions. The standard 0.2 internal pressure and 0.3 internal suctionshould be entered for each wind direction. In the example below are largerinternal pressure value may be required in the W3 direction due to the dominantopening.</p><p>W7 270 degree winddirection</p><p>W3 90 degree wind direction</p></li><li><p>8/10/2019 MasterKey Wind Loading to BS 6399</p><p> 13/31</p><p>MasterKey Wind Loading to BS 6399 20-13</p><p>For wind direction W3 it is clear that an internal pressure value is required, whilefor wind direction W7 an internal suction value is needed.</p><p>6.2.4 Setting up load cases including internal pressure and suction</p><p>All the relevant load case combinations which include wind loading can beautomatically generated with the click of a few buttons. These facilities are found</p><p>in the wind directions are and can be accessed by clicking on the button atthe top right of the screen in the Wind Area Loading part of the program.</p><p>All ultimate and service load cases are developed in combination with the deadand live loads, and taking into account any pressure or suction coefficients addedto the wind data.</p><p>To generate all wind loading cases,</p><p>1. Click on the D+W button to set up the ultimate dead plus wind case forW1</p><p>2. Click on the D+L+W button to add the ultimate dead plus live plus windcase for W1</p><p>3. Click on the...</p></li></ul>

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