SOFTWARE FUNCTION

WinMAST is a program for the rapid description and analysis of lattice towers and masts supporting aerials and ancillary equipment. The speed at which a mast model may be modified and re-analysed makes WinMAST the ideal tool both for initial mast design and for the assessment of existing masts for the effects of either altering antennae positions or adding new equipment.

MAST GEOMETRY SCREEN

The mast planform may be either triangular, square or hexagonal. The leg spacing at the top of the mast is specified and the geometry of the rest of the mast face is then described in sections. Working down the mast from the top, the defined data for each face section is, the height of the section, the leg spacing at the bottom of the section, the number of panels in the section, the type of bracing (currently either < or X), and the leg and bracing member sections and sizes.

WIND LOADING SCREEN

Wind loads can be calculated to CP3: Chapter V or to BS6399 requirements. For CP3: Chapter V, the user enters the Gust Wind Speed and the adjustment factors for Topography, Terrain category, Probability and wind Direction. For BS6399, the user enters Mean Wind Speed and the adjustment factors for Altitude, wid Direction, Season, Probability and mast Location. The mast base level may be specified. Local antenna loads, to include torque if required, are specified and distributed loads representing ladders, cables, wave guides etc are entered.

DESIGN PARAMETERS

Leg and bracing member steel grades may be entered as separate values. Effective length factors to be used in the member checks may be specified. A slenderness ratio limit may be set and a mast self-weight factor may be specified.

FORMULAE ANALYSIS OPTION

The Formulae Analysis option provides an instantaneous calculation of wind loads for all panels in the mast. Ultimate moments, shears and torques are calculated at the bottom of each section; values are given for both on-face wind and on-corner wind. Leg and Bracing Check screens show the member section used, the effective length, the slenderness ratio, the compressive resistance Pc, the critical wind direction, the ultimate load Fc and the load/strength ratio Fc/Pc marked PASS or FAIL as appropriate.

WinFRAM ANALYSIS OPTION

The WinFRAM Analysis option automatically builds a full 3D space frame model of the mast and loading and analyses the model by the matrix stiffness method. Detailed results show the member forces, base reactions and structure movement throughout the mast. Members may be checked individually using the optional WinSTEEL program which uses the WinFRAM results file as input. Vibration of the mast may be examined using the optional WinVIBE program to calculate frequencies and mode shapes for natural modes of vibration.

Interfacing products:WinFRAM, WinSTEEL, WinVIBE