In Ftool it is possible to configure:
- Sizes of supports, hinges, loads, and text in the display of a model on the screen;
- Option to consider or not static load results in the calculation of envelopes of internal forces due to load-trains;
- Option to save auxiliary file (extension ".pos") that is used internally to link the program with is analysis module (solver). By default, this option is not activated, and it is reset when a new model is initialized or open from file.
- Unit systems and the format for numerical values.
In the current version of Ftool, the only type of analysis is linear-elastic:
There are itens in Options menu that allow the configuration of sizes of supports, hinges, loads, and text in the display of a model on the screen:
For each type of entity, display size may be Small, Medium, or Large. An example of the results of this display size configuration may be seen in the model of a bridge:
Ftool, by default, adds static load effects to the calculation of internal force envelopes due to load-trains. This option may be deactivated through one item of Options menu. The default configuration is reset when a new model is created or opened from a file.
Ftool has an internal module to perform the analysis (solver) of current model. It is possible to save an auxiliary file with the data that is passed to the analysis module. In version previous to version 3.00, this file was the only option to feed the analysis. After version 3.00, this communication is done through RAM memory. However, there is an item in the Options menu that allows this file to be saved. The file has the same name as the current model file name, but with the extension ".pos". This option is deactivated when a new model is created or open from a file.
Through the sub-menu Units & Number Formatting, the user selects physical units for parameters used in the structural analysis and the format for the display of numerical values for these parameters. Options exist to specify units in SI (International System), US (American System), or units in kilo-Newtons and meters. To specify a system of units and the display format, select the corresponding button at the top of the box. The user can always switch the system of units or formatting as needed during an analysis.
The following tables show the unit systems implemented in Ftool for each parameter and the corresponding factors of conversion for the units used internally by the program (indicated in bold-face).
The first unit of each parameter appears automatically when the user selects SI units (International System) or US units (American System).
The conversions for units that have ton-force (tf) are:
1 tf = 103 kg×gThe gravity acceleration adopted is g = 9.81 m/seg2.
Pascal Units:
1 Pa = 1 N/m2
1 kPa = 103 N/m2 = 1 kN/m2
1 MPa = 106 N/m2 = 103 kN/m2 = 1 N/mm 2
1 GPa = 109 N/m2 = 106 kN/m2 = 1 kN/mm2
Parameter SI units
US units
Symbol Name Factor of Symbol Name Fator da ref. SI unit ref. SI unit Distance m meter 1.0 ft foot 0.3048 and Length cm centimeter 0.01 in inch 0.0254 mm millimeter 0.001 Displacement mm millimeter 0.001 in inch 0.0254 cm centimeter 0.01 ft foot 0.3048 m meter 1.0 Rotation rad radian 1.0 rad radian 1.0 deg degree p/180.0 deg degree p/180.0 mm millimeter 0.001 in inch 0.0254 Seção cm centimeter 0.01 ft foot 0.3048 m meter 1.0 Section Area mm2 0.000001 in2 inch2 0.02542 cm2 0.0001 ft2 foot2 0.30482 m2 1.0 Section inertia mm4 1.0e-12 in4 inch4 0.02544 cm4 1.0e-08 ft4 foot4 0.30484 m4 1.0 Force kN kilo-Newton 1.0 kip kilo-pound 4.448 N Newton 0.001 lb pound 0.004448 tf ton (weight) 9.81 Moment kNm 1.0 ft-k kip×foot 1.356 Nm 0.001 ft-lb foot×pound 0.001356 tfm 9.81 in-k inch×kip 0.11298 kNcm 0.01 in-lb inch×pound 0.00011298 Ncm 0.00001 tfcm 0.0981 kNmm 0.001 Nmm 0.000001 tfmm 0.00981 Distributed kN/m 1.0 k/ft kip/foot 14.593 Load N/m 0.001 lb/ft pound/foot 0.014593 tf/m 9.81 k/in kip/inch 175.1 kN/cm 100.0 lb/in pound/inch 0.1751 N/cm 0.1 tf/cm 981.0 kN/mm 1000.0 N/mm 1.0 tf/mm 9810.0 Temperature °C centigrade 1.0 °F Fahrenheit (T-32)×5/9 Elasticity MPa mega-Pascal 1000.0 ksi kip/inch2 6895.0 Modulus GPa giga-Pascal 1000000.0 psi pound/inch2 6.895 tf/mm2 9810000.0 k/ft2 kip/foot2 47.878 N/cm2 10.0 lb/ft2 pound/foot2 0.047878 kN/cm2 10000.0 tf/cm2 98100.0 Pa Pascal (N/m2) 0.001 kN/m2 kilo-Pascal 1.0 tf/m2 9.81 Specific Weight kN/m3 1.0 pcf pound/foot3 0.1571 N/m3 0.001 k/ft3 kip/foot3 157.1 tf/m3 9.81 lb/in3 pound/inch3 271.434 kN/cm3 1000000.0 k/in3 kip/inch3 271434.0 N/cm3 1000.0 tf/cm3 9810000.0 kN/mm3 1.0e+09 N/mm3 1000000.0 tf/mm3 9.81e+09 Thermal Expan. 1/°C 1.0 1/°F 1.8 Translational kN/m 1.0 k/ft kip/foot 14.593 Spring N/m 0.001 lb/ft pound/foot 0.014593 Stiffness tf/m 9.81 k/in kip/inch 175.1 kN/cm 100.0 lb/in pound/inch 0.1751 N/cm 0.1 tf/cm 981.0 kN/mm 1000.0 N/mm 1.0 tf/mm 9810.0 Rotational kNm/rad 1.0 ft-k/rad foot×kip/rad 1.356 Spring Nm/rad 0.001 ft-lb/rad foot×pound/rad 0.001356 Stiffness tfm/rad 9.81 in-k/rad inch×kip/rad 0.11298 kNcm/rad 0.01 in-lb/rad inch×pound/rad 0.00011298 Ncm/rad 0.00001 ft-k/deg foot×kip/deg 244.08/p tfcm/rad 0.0981 ft-lb/deg foot×pound/deg 0.24408/p kNm/rad 0.001 in-k/deg inch×kip/deg 20.3364/p Nm/rad 0.000001 in-lb/deg inch×pound/deg 0.0203364/p tfm/rad 0.00981 kNm/deg 180.0/p Nm/deg 0.18/p tfm/deg 1765.8/p kNcm/deg 1.8/p Ncm/deg 0.0018/p tfcm/deg 17.658/p kNm/deg 0.18/p Nm/deg 0.00018/p tfm/deg 1.7658/p