Structural Family Parameters

When creating a structural family parameter, specify the parameter type in the Parameter Properties dialog.

In the Family Editor, click Create tabProperties panel (Family Types). In the Family Types dialog, under Parameters, click Add. For Discipline, select Structural. For Type of Parameter, select one of the following.

Name	Description	Units
Force	Used to define the exertion of one object on another. Applies to Point Load force parameters.	force
Linear Force	Used to define the intensity of force per unit length. Applies to Line Loads force parameters.	force/length
Area Force	Used to define the intensity of force per unit area. Applies to Area Loads force parameters.	force/length^2
Moment	Used to define the tendency of a force to rotate an object about an axis. Mathematically moment of force is defined as the cross product of the lever-arm distance vector and the force vector. Applies to Point Load moment parameters.	force*length
Linear Moment	Used to define the intensity of moment per unit length. Applies to Line Loads moment parameters.	force*length/length
Stress	Used to define the physical quantity that internal force exerts upon an adjoining particles. Mathematically stress is defined as division of the force vector per area.	force/length^2
Unit Weight	Used to define the weight per unit volume of an object.	force/length^3
Weight	Used to define the force exerted on an object by gravity.	force
Mass	Used to define the quantity of matter in a object.	mass
Mass per Unit Area	Used to define the mass density per unit area of a surface of an object. Applies to the floor mass per unit area.	mass/length^2
Thermal Expansion Coefficient	Used to define the change in the length dimensions of an object to a change in temperature. For linear elements it is calculated as the material degree of expansion divided by the change in temperature for a unit length.	1 / temperature
Point Spring Coefficient	Used to define the ratio of force affecting the spring at a point to its resulting displacement. Applies to the Spring Modulus parameter in Point Boundary Conditions.	force/length
Line Spring Coefficient	Used to define the ratio of force affecting the spring along a line to its resulting displacement. Applies to the Spring Modulus parameter in Line Boundary Conditions.	force/length^2
Area Spring Coefficient	Used to define the ratio of force affecting the spring spanning an area to its resulting displacement. Applies to the Spring Modulus parameter in Area Boundary Conditions.	force/length^3
Rotational Point Spring Coefficient	Used to define the torque ratio of force affecting the spring at a point to its resulting displacement. Applies to the Spring Modulus parameter in Point Boundary Conditions.	force*length/angle
Rotational Line Spring Coefficient	Used to define the torque ratio of force affecting the spring along a line to its resulting displacement. Applies to the Spring Modulus parameter in Line Boundary Conditions.	force*length/angle/length
Displacement/Deflection	Used to define the linear distance between the start and end points of the motion of an object.	length
Rotation	Used to define the arc distance of a rotation.	angle
Period	Used to measure the duration of a single cycle of a repeating action.	time
Frequency	Used to measure the number of cycles of a repeating action in a unit of time.	1/time
Pulsation	Used to define the rate or arc distance traveled for a wave per unit of time.	2*Pi/time
Velocity	Used to define the rate at which the position of an object changes in time. Mathematically velocity is defined as division of the distance per time.	length/time
Acceleration	Used to define the rate at which the position of an object changes its velocity. Mathematically velocity is defined as division of the velocity per time.	length/time^2
Energy	Used to define the amount of force required to displace an object.	force*length
Reinforcement Volume	Used to define the assumed total volume of rebar in an object.	length^2
Reinforcement Length	Used to define the assumed total length of rebar in an object.	length
Reinforcement Area	Used to define the assumed total area of rebar in an object.	length^3
Reinforcement Area per Unit Length	Used to define the assumed total area of rebar per unit of a floor cross section length in an object.	length^2/length
Reinforcement Spacing	Used to define the assumed spacing between rebar in an object.	length
Reinforcement Cover	Used to define the assumed distance between rebar and the exterior surface of its host.	length
Bar Diameter	Used to define the assumed diameter of rebar used to reinforce the object.	length
Crack Width	Used to define the acceptable assumed widths of cracking in a reinforced object.	length
Section Dimension	Used to define a linear dimension of a framing element cross section.	length
Section Property	Used to define a detailing dimension of a framing element cross section.	length
Section Area	Used to define the area of a framing element cross section.	length^2
Section Modulus	Used to define a geometric proportionality between stress and strain of a framing element cross section. Mathematically, it is Moment of Inertia of the framing element section divided by the dimension to the external fiber from the section center of gravity.	length^3
Moment of Inertia	Used to define the mass property of a rigid body that determines the torque needed for angular acceleration about an axis of rotation. Applies to the section properties on a framing element.	length^4
Warping Constant	Used to define the consistent measure of stress used to calculate warping.	length^6
Mass per Unit Length	Used to define the linear mass density of a framing element object.	mass/length
Weight per Unit Length	Used to define the linear weight of a framing element object.	force/length
Surface Area per Unit Length	Used to define the linear surface area of an object. Applies to the painting surface area of a framing element per unit length.	length^2/length