Section Properties

Section List
Display section data contained in the existing fn.MCB file.

Selected List
Select section data to be imported and register them in the Selected List.

Note 

If a fn.MCB is selected, all the section data contained in the existing fn.MCB file are registered in the Selected List.

Numbering Type
Specify the Import mode for section numbers.

Keep ID

Import the data keeping the same section numbers.

New ID

Assign new numbers to the imported section data.

Start number

Assign a new starting number for the material to be modified.

Increment

Enter the increment for numbering material property numbers.

Change element's material number

Modify a material property number. Using this option will modify the previously defined material property number. If this option is not checked, the selected material having previously defined number will become undefined and the additional user-defined material number will be created without any assigned elements.

Offset : Specify the section Offset from the location options shown in the figure below.

Horizontal Offset : Specify the Offset in the transverse direction. "to Extreme Fiber" assigns the offset to the outer-most point. For a specific location of Offset, select 'User"and enter the distance from the "Centroid" to the desired Offset location. Unless the Offset is "Center-Center" the Horizontal Offset can be entered as the "User" type. For a tapered (non-prismatic) section, data input for the J-end also becomes activated.

Vertical Offset : Specify the Offset in the vertical direction. "to Extreme Fiber" assigns the offset to the outer-most point. For a specific location of Offset, select "User" and enter the distance from "Centroid" to the desired Offset location. Unless the Offset is "Center-Center" the Vertical Offset can be entered as the "User" type. For a tapered (non-prismatic) section, data input for the J-end also becomes activated.

Note 1

When Offset distance is specified, a positive (+) sign applies to Center-to-outward for Centroid reference and Extreme-to-inward for Extreme Fiber reference.

User Offset Reference : When section offset distance is specified as the "User" type, define the reference location.

Centroid : Specify the offset distance relative to the centroid of the section.

Extreme Fiber(s) : Specify the offset distance relative to Left/Right & Top/Bottom.

Note 2

When User type is specified, the Offset distance and direction are entered relative to Centroid irrespective of the Center option (Centroid or Center of Section). For example, specifying "Offset: Left-Center", "Center Loc.: Center of Section" and "Horizontal offset: 0.5 " User type" will result in an Offset 0.5" to the left of the Centroid. And if the Offset option is "Left-Center" and the Center option is Center of Section the User type for Horizontal offset becomes activated and the User type for Vertical offset becomes inactivated. The Horizontal offset defined as User type here becomes the Centroid, and the Vertical offset fixed to Center becomes the "Center of Section"

Note 3

When FCM Wizard is used, and "Apply the Centroid of Pier Table Section Option" is selected, the node locations of the girder will be changed as follows :

Offset : Center-Top

User Offset Reference: Extreme Fiber(s)

Vertical Offset: User, Offset Distance (i & j) = Pier Table section height-Centroid of Pier Table section

Note 4 Usage tip of Section Offset

The Display Offset Point button : Display the Offset specified from the Change Offset dialog box in the guide diagram of Section Data window.

Area : Cross sectional area

Asy : Effective Shear Area for shear force in the element's local y-direction

It becomes inactive when Shear Deformation is not considered.

Asz : Effective Shear Area for shear force in the element's local z-direction

It becomes inactive when Shear Deformation is not considered.

Ixx : Torsional Resistance about the element's local x-axis

Iyy : Moment of Inertia about the element's local y-direction

Izz : Moment of Inertia about the element's local z-direction

Cyp : Distance from the section's neutral axis to the extreme fiber of the element in the local (+)y-direction

Cym : Distance from the section's neutral axis to the extreme fiber of the element in the local (-)y-direction

Czp : Distance from the section's neutral axis to the extreme fiber of the element in the local (+)z-direction

Czm : Distance from the section's neutral axis to the extreme fiber of the element in the local (-)z-direction

Qyb : Shear Coefficient for the shear force applied in the element's local z-direction

Qzb : Shear Coefficient for the shear force applied in the element's local y-direction

Peri : O : Total perimeter of the section

Peri : I : Inside perimeter length of a hollow section

y1, z1 : Distance from the section's neutral axis to the Location 1 (used for computing combined stress)

y2, z2 : Distance from the section's neutral axis to the Location 2 (used for computing combined stress)

y3, z3 : Distance from the section's neutral axis to the Location 3 (used for computing combined stress)

y4, z4 : Distance from the section's neutral axis to the Location 4 (used for computing combined stress)

Zyy : Plastic Section Modulus about the element local y-direction

Zzz : Plastic Section Modulus about the element local z-direction

The cross-sectional area of a member is used to compute axial stiffness and stress when the member is subjected to a compression or tension force. Figure 1 illustrates the calculation procedure.

Cross-sectional areas could be reduced due to member openings and bolt or rivet holes for connections. midas does not consider such reductions. Therefore, if necessary, the user is required to modify the values using the option 2 above and his/her judgment.

Area = +dA = A1 + A2 + A3 = (300 x 15) + (573 x 10) + (320 x 12) = 14070

Fig. Example of cross-sectional area calculation

The effective shear areas of a member are used to formulate the shear stiffness in the y- and z-axis directions of the cross-section.

If the effective shear areas are omitted, the shear deformations in the corresponding directions are neglected.

When midas computes the section properties by the option 1 or 3, the corresponding shear stiffness components are automatically calculated. Figure 2 outlines the calculation methods.

Asy : Effective shear area in the ECS y-axis direction

Asz : Effective shear area in the ECS z-axis direction

Fig. Effective Shear Area calculations

Torsional resistance refers to the stiffness resisting torsional moments. It is expressed as

<Eq. 1>

where,

Ixx: Torsional Constant

T: Torsional moment or torque

G: Shear Modulus of Elasticity

θ : Angle of twist

The torsional stiffness expressed in Eq. 1 must not be confused with the polar moment of inertia that determines the torsional shear stresses. However, they are identical to one another in the cases of circular or thick cylindrical sections.

No general equation exists to satisfactorily calculate the torsional resistance applicable for all section types. The calculation methods widely vary for open and closed sections and thin and thick thickness sections.

For calculating the torsional resistance of an open section, an approximate method is used; the section is divided into several rectangular sub-sections and then their resistances are summed into a total resistance, Ixx, calculated by the equation below.

<Eq. 2>

for a e b

where,

Ixx: Torsional resistance of a (rectangular) sub-section

2a: Length of the longer side of a sub-section

2b: Length of the shorter side of a sub-section

Figure 3 illustrates the equation for calculating the torsional resistance of a thin walled, tube-shaped, closed section.

<Eq. 3>

where,

A : Area enclosed by the mid-line of the tube

ds : Infinitesimal length of thickness centerline at a given point

t : Thickness of tube at a given point

For those sections such as bridge box girders, which retain the form of thick walled tubes, the torsional stiffness can be obtained by combining the above two equations, Eq. 1 and Eq. 3.

Torsional resistance:

Shear stress at a given point:

Thickness of tube at a given point: ts

Fig. Torsional resistance of a thin walled, tube-shaped, closed section

Fig. Torsional resistance of solid sections

Fig. Torsional resistance of thin walled, closed sections

Fig. Torsional resistance of thick walled, open sections

Fig. Torsional resistance of thin walled, open sections

In practice, combined sections often exist. A combined built-up section may include both closed and open sections. In such a case, the stiffness calculation is performed for each part, and their torsional stiffnesses are summed to establish the total stiffness for the built-up section.

For example, a double I-section shown in Figure 8(a) consists of a closed section in the middle and two open sections, one on each side.

<Eq. 4>

<Eq. 5>

<Eq. 6>

Figure 8(b) shows a built-up section made up of an I-shaped section reinforced with two web plates, forming two closed sections. In this case, the torsional resistance for the section is computed as follows:

If the torsional resistance contributed by the flange tips is negligible relative to the total section, the torsional property may be calculated solely on the basis of the outer closed section (hatched section) as expressed in Eq. 7.

<Eq. 7>

If the torsional resistance of the open sections is too large to ignore, then it should be included in the total resistance.

(a) Section consisted of closed and open sections

(b) Section consisted of two closed sections

Fig. Torsional resistance of built-up sections

The area moment of inertia is used to compute the flexural stiffness resisting bending moments. It is calculated relative to the centroid of the section.

<Eq. 8>

-Area moment of inertia about the ECS z-axis

<Eq. 9>

: area

: distance from the reference point to the centroid of the section element in the z-axis direction

: distance from the reference point to the centroid of the section element in the y-axis direction

: first moment of area relative to the reference point in the y-axis direction

: first moment of area relative to the reference point in the z-axis direction

Fig. Example of calculating area moments of inertia

The area product moment of inertia is used to compute stresses for non-symmetrical sections, which is defined as follows:

<Eq. 10>

Sections that have at least one axis of symmetry produce Iyz=0. Typical symmetrical sections include I, pipe, box, channel and tee shapes, which are symmetrical about at least one of their local axes, y and z. However, for non-symmetrical sections such as angle shaped sections, where Iyz`0, the area product moment of inertia should be considered for obtaining stress components.

The area product moment of inertia for an angle is calculated as shown in Figure 10.

Fig. Area product moment of inertia for an angle

Fig. Bending stress distribution of a non-symmetrical section

The neutral axis represents an axis along which bending stress is 0 (zero). As illustrated in the right-hand side of Figure 11, the n-axis represents the neutral axis, to which the m-axis is perpendicular. Since the bending stress is zero at the neutral axis, the direction of the neutral axis can be obtained from the relation defined as

<Eq. 11>

The following represents a general equation applied to calculate the bending stress of a section:

<Eq. 12>

In the case of an I shaped section, Iyz=0, hence the equation can be simplified as:

<Eq. 13>

where,

Iyy : Area moment of inertia about the ECS y-axis

Izz : Area moment of inertia about the ECS z-axis

Iyz : Area product moment of inertia

y : Distance from the neutral axis to the location of bending stress calculation in the ECS y-axis direction

z : Distance from the neutral axis to the location of bending stress calculation in the ECS z-axis direction

My : Bending moment about the ECS y-axis

Mz : Bending moment about the ECS z-axis

The general expressions for calculating shear stresses in the ECS y and z-axes are:

<Eq. 14>

<Eq.15>

where,

Vy : Shear force in the ECS y-axis direction

Vz : Shear force in the ECS z-axis direction

Qy : First moment of area about the ECS y-axis

Qz : First moment of area about the ECS z-axis

by : Thickness of the section at which a shear stress is calculated, in the direction normal to the ECS z-axis

bz : Thickness of the section at which a shear stress is calculated, in the direction normal to the ECS y-axis

The first moment of area is used to compute the shear stress at a particular point on a section. It is defined as follows:

<Eq. 16>

<Eq. 17>

When a section is symmetrical about at least one of the y and z-axis, the shear stresses at a particular point are:

<Eq. 18>

<Eq. 19>

where,

Vy : Shear force acting in the ECS y-axis direction

Vz : Shear force acting in the ECS z-axis direction

Iyy : Area moment of inertia about the ECS y-axis

Izz : Area moment of inertia about the ECS z-axis

by : Thickness of the section at the point of shear stress calculation in the ECS y-axis direction

bz : Thickness of the section at the point of shear stress calculation in the ECS z-axis direction

The shear factor is used to compute the shear stress at a particular point on a section, which is obtained by dividing the first moment of area by the thickness of the section.

<Eq. 20>

<Eq. 21>

Fig. Example of calculating a shear factor

midas calculates the stiffness for a full composite action of structural steel and reinforced concrete. Reinforcing bars are presumed to be included in the concrete section. The composite action is transformed into equivalent section properties.

The program uses the elastic moduli of the steel (Es) and concrete (Ec) defined in the SSRC79 (Structural Stability Research Council, 1979, USA) for calculating the equivalent section properties. In addition, the Ec value is decreased by 20% in accordance with the EUROCODE 4.

- Equivalent cross-sectional area

- Equivalent effective shear area

- Equivalent area moment of inertia

where,

Ast1 : Area of structural steel

Acon : Area of concrete

Asst1 : Effective shear area of structural steel

Ascon : Effective shear area of concrete

Ist1 : Area moment of inertia of structural steel

Icon : Area moment of inertia of concrete

REN : Modular ratio (elasticity modular ratio of the structural steel to the concrete, Es/Ec)

- Equivalent torsional coefficient

1. Divide the section into four quadrants.

2. Assign the positions furthermost from the centroid in each quadrant for checking stresses.

If the webs of a section are extensively sloped as in the above diagram, the points furthermost from the centroid may not be the lowest points of the section. Use caution that the stress checking positions of quadrants 3 & 4 may be selected differently from the expectation.

The section data can be entered by the following 2 methods in the dialog box :

1. Select a section from the DB (database) of the standard sections for a country.

2. Enter the main dimensions of a standardized section shape.

Section Shape List: Select a section shape (Angle, Channel, H-Section, T-Section, Box, Pipe, Double Angle, Star-battened Angle, Double Channel, Solid Rectangle, Solid Round, Octagon, Solid Octagon, R-Octagon, Track, Solid Track, Half Track, Cold Formed Channel, U-Rib & Inverted T-section).

User : Enter the main dimensions of a standardized section shape.

H, B1, ... : Refer to the dimension information diagram in the dialog box.

DB: Select a section from the DB of the standard sections for a country.

AISC2K(US) : American Institute of Steel Construction, 2000 US Unit : lb, in

AISC2K(SI) : American Institute of Steel Construction, 2000 SI Unit : kN, m, mm

AISC : American Institute of Steel Construction

CISC02(US) : Canadian Institute of Steel Construction (US Unit : lb, in)

CISC02(SI) : Canadian Institute of Steel Construction (SI Unit : kN, m, mm)

BS(S) : British Standard

Note

BS indicates BS4-1 revised prior to 1993.

BS4 - 93 : British Standard / BS 4-1 : 1993

DIN : Deutches Institut fur Normung e.v

UNI : Italian National Standard

GOST : Russian National Standard

STO_ASChM : Russian National Standard

JIS2K : Japanese Industrial Standards 2000

JIS : Japanese Industrial Standards

KS : Korean Industrial Standards

GB-YB05 : Guojia Biao Zhun-Yejin Bu Biao Zhun

Pacific(SI) : Bentley Pacific Standards (SI Unit : kN, m, mm)

IS84 : Indian Standards

GB-YB05 : Guojia Biao Zhun-Yejin Bu Biao Zhun(2005)

CNS91 : Taiwan Standards

Sect. Name : Enter directly a DB section name or select a desired DB from the Section list. When the section name is directly entered, it must correspond to the format of the DB section names.

Ex) AISC: W36x280, BS: UB 406x178x54, DIN: HD400x288

Note

When specifying Double Angle or Double Channel sections, assign the sectional shape in the list and select User. Then, select DB and Sect. Name from Get Data from Single Angle (or Channel) or directly enter the main dimensions of the section.

The section data data can be entered by the following 3 methods in the dialog box :

1. Select a section from the DB (database) of the standard sections for a country.

2. Enter the main dimensions of a standardized section shape.

3. Import a section generated from SPC module.

Section Shape List : Assign a section shape to use.

Built-Up Section : Fabricated section

Note

Check in the case of a built-up section and leave it blank in the case of a rolled steel section. The data is referred to for strength verification for steel members and compiling material quantities in BOM.

Size

H, B1, ... : Refer to the diagram denoting section dimensions in the dialog box.

The structure can be analyzed only with the stiffness data even if the section dimensions are not specified.

Section Properties

The main section dimensions entered in Size are used to calculate and display the section stiffness.

Area : Cross sectional area

Asy : Effective Shear Area for shear force in the element's local y-direction

It becomes inactive when Shear Deformation is not considered.

Asz : Effective Shear Area for shear force in the element's local z-direction

It becomes inactive when Shear Deformation is not considered.

Ixx : Torsional Resistance about the element's local x-axis

Iyy : Moment of Inertia about the element's local y-direction

Izz : Moment of Inertia about the element's local z-direction

Cyp : Distance from the section's neutral axis to the extreme fiber of the element in the local (+)y-direction

Cym : Distance from the section's neutral axis to the extreme fiber of the element in the local (-)y-direction

Czp : Distance from the section's neutral axis to the extreme fiber of the element in the local (+)z-direction

Czm : Distance from the section's neutral axis to the extreme fiber of the element in the local (-)z-direction

Qyb : Shear Coefficient for the shear force applied in the element's local z-direction

Qzb : Shear Coefficient for the shear force applied in the element's local y-direction

Peri : O : Total perimeter of the section

Peri : I : Inside perimeter length of a hollow section

Note

The value of Peri:I is '0' for an I-shaped section since the section is not hollow.

Cent : y : Centroidal distance in ECS y-axis

Cent : z : Centroidal distance in ECS z-axis

y1, z1 : Distance from the section's neutral axis to the Location 1 (used for computing combined stress) The user may specify the location of the stress display.

y2, z2 : Distance from the section's neutral axis to the Location 2 (used for computing combined stress) The user may specify the location of the stress display.

y3, z3 : Distance from the section's neutral axis to the Location 3 (used for computing combined stress) The user may specify the location of the stress display.

y4, z4 : Distance from the section's neutral axis to the Location 4 (used for computing combined stress) The user may specify the location of the stress display.

Zyy : Plastic Section Modulus about the element local y-direction

Zzz : Plastic Section Modulus about the element local z-direction

Enter the section property data for steel RC composite members in the dialog box.

Shape : Assign a section shape to use.

Note

New Cross I Section and Combined T-Section were incorporated.

Concrete Data : Enter the outer dimensions of the RC section of a steel-encased concrete section.

Steel Data : Enter the steel section data.

User : Enter the main dimensions of a standardized section shape.

H, B1, ... : Refer to the dimension information diagram in the dialog box.

DB : Select a section from the DB of the standard sections for a country.

AISC2K(US) : American Institute of Steel Construction, 2000 US Unit : lb, in

AISC2K(SI) : American Institute of Steel Construction, 2000 SI Unit : kN, m, mm

AISC : American Institute of Steel Construction

CISC02(US) : Canadian Institute of Steel Construction (US Unit : lb, in)

CISC02(SI) : Canadian Institute of Steel Construction (SI Unit : kN, m, mm)

BS(S) : British Standard

Note

BS indicates BS4-1 revised prior to 1993.

BS4 - 93 : British Standard / BS 4-1 : 1993

DIN(S) : Deutches Institut fur Normung e.v

JIS2K : Japanese Industrial Standards 2000

JIS : Japanese Industrial Standards

KS : Korean Industrial Standards

GB-YB : Guojia Biao Zhun-Yejin Bu Biao Zhun

Pacific(SI) : Bentley Pacific Standards (SI Unit : kN, m, mm)

IS84 : Indian Standards

CNS91 : Taiwan Standards

Steel Name: Enter directly a DB section name or select a desired DB from the Section list. When the section name is directly entered, it must correspond to the format of the DB section names.

Ex) AISC: W36x280, BS: UB 406x178x54, DIN: HD400x288, JIS, KS: H 400x200x8/13

Material : Enter material properties for steel and concrete constituting steel RC composite sections.

Click the Select Material from DB... button to select the material properties for steel and concrete stored in the DB for a country. The following items are automatically entered:

Es/Ec : Modulus of Elasticity Ratio of steel relative to concrete

Ds/Dc : Specific Weight (Density) Ratio of steel relative to concrete

Ps : Poisson's Ratio for steel

Pc : Poisson's Ratio for concrete

Combined Ratio of Conv. : Stiffness Reduction Factor of concrete [Default = 1.0]

Note

When RC is converted into steel for calculating the SRC section stiffness, Conv. Stiffness Factor is applied to reduce the stiffness of RC.

Replace : Assign Steel to be the reference when calculating stiffness of a composite section

Note

MIDAS/Civil converts RC into equivalent steel for SRC section stiffness calculation.

In this dialog box, enter the section properties for a combined section made up by two standard section types.

User : Enter the main dimensions of standardized section shapes.

DB : Select the sections from the DB of the standard sections for a country.

AISC2K(US) : American Institute of Steel Construction, 2000 US Unit : lb, in

AISC2K(SI) : American Institute of Steel Construction, 2000 SI Unit : kN, m, mm

AISC : American Institute of Steel Construction

CISC02(US) : Canadian Institute of Steel Construction (US Unit : lb, in)

CISC02(SI) : Canadian Institute of Steel Construction (SI Unit : kN, m, mm)

BS(S) : British Standard

Note

BS indicates BS4-1 revised prior to 1993.

BS4 - 93 : British Standard / BS 4-1 : 1993

DIN(S) : Deutches Institut fur Normung e.v

JIS2K : Japanese Industrial Standards 2000

JIS : Japanese Industrial Standards

KS : Korean Industrial Standards

GB-YB : Guojia Biao Zhun-Yejin Bu Biao Zhun

Pacific(SI) : Bentley Pacific Standards (SI Unit : kN, m, mm)

IS84 : Indian Standards

CNS91 : Taiwan Standards

Data 1, Data 2 : Enter the section data for individual components constituting the combined section.

Sect. Name : Enter directly a DB section name or select a desired DB from the Section list. When the section name is directly entered, it must correspond to the format of the DB section names.

Ex) AISC: W36x280, BS: UB 406x178x54, DIN: HD400x288, JIS, KS: H 400x200x8/13

H, B, ... : Refer to the diagram denoting section dimensions in the dialog box.

Note Applicable composite section DB for design

1. Design code : KSSC-ASD03, AISC-ASD89, TWN-ASD90

2. Section DB : H-T Combined Shape, 2T(Web Opened H), H-Shape with 2T or Web

In this dialog box, enter the section properties for both ends of a line element to define a non-uniform section (Non-prismatic Section/ Tapered Section) of identical shape.(Refer to Note)

Section Shape List : Applicable tapered section shapes are shown below. For PSC, Composite Type or General Section of Value type, pre-defined sections can be brought in from the Section DB.

DB/User : All sections except for the R-Octagon section

Value : All sections except for the R-Octagon section

PSC : All PSC Type sections

Composite : Typical 4 composite sections (Steel-Box, Steel-I, PSC-I & PSC-T)

Value : Assign value when the user directly enters the section stiffness data.

Enter the section dimensions for section-i and j separately and click the Calculate Stiffness button. Then, the user may modify the auto-calculated stiffness data or directly enter the stiffness data without entering the section dimensions.

User : Enter the main dimensions of standardized section shapes.

DB : Select the sections from the DB of the standard sections for a country.

AISC2K(US) : American Institute of Steel Construction, 2000 US Unit : lb, in

AISC2K(SI) : American Institute of Steel Construction, 2000 SI Unit : kN, m, mm

AISC : American Institute of Steel Construction

CISC02(US) : Canadian Institute of Steel Construction (US Unit : lb, in)

CISC02(SI) : Canadian Institute of Steel Construction (SI Unit : kN, m, mm)

BS(S) : British Standard

DIN(S) : Deutches Institut fur Normung e.v

JIS2K : Japanese Industrial Standards 2000

JIS : Japanese Industrial Standards

KS : Korean Industrial Standards

GB-YB : Guojia Biao Zhun-Yejin Bu Biao Zhun

Pacific(SI) : Bentley Pacific Standards (SI Unit : kN, m, mm)

IS84 : Indian Standards

CNS91 : Taiwan Standards

Section-i, Section-j : Enter directly each section name corresponding to the starting section-i and the ending section-j or select the desired DB from the section list to describe the tapered section. When the section names are directly entered, they must correspond to the DB section name format.

Ex) AISC: W36x280, BS: UB 406x178x54, DIN: HD400x288, JIS, KS: H 400x200x8/13

y Axis Variation : Dimensional variation affects the moment of inertia about the element local y-axis along the length.

z Axis Variation : Dimensional variation affects the moment of inertia about the element local z-axis along the length.

Linear : linear variation along the element local x-direction

Parabolic : parabolic variation along the element local x-direction

Cubic : cubic variation along the element local x-direction

Note 1

Calculation of section properties as per Dimensional Variation

Note 2

In the results produced in contours, diagrams and tables, dimensional variation in the axial direction affects the moment of inertia only. In Beam Detail Analysis, section properties are directly calculated at 1/4, 1/2 and 3/4 points using the shape information. As such, dimensional variation affects all the section properties (A, Asy, Asz, Ixx, Iyy & Izz).

In this dialog box, the sectional data pertaining to the "Analysis considering the section variation before and after composite actions in Composite Bridges" are specified.

Section Type : Assign a section type

Steel-Box : Structural steel Box Girder

Steel -I : Structural Steel I Shape Girder

User : Section properties defined as General Section in the Value Tab

Slab Width / Girder Num. & CTC

Slab Width : Total width of slab (used for calculating lateral flexure stiffness after becoming composite)

Girder

Num. : Number of girders within the total slab

CTC : Center to center spacing between girders

Note 1

In case when the number of girders is 1 in a structure, enter 1 for Number of girders (Num) and enter 0 for center to center spacing (CTC).

Slab 

Bc : Effective slab width for one girder

tc : Thickness of slab

Hh : Distance from the top of girder to the underside of slab

Girder

Material

Click [Select Material from DB...] button to select the material properties for steel and concrete stored in the DB for a country. The following items are automatically entered.

Es/Ec : ModulusRatio, steel to concrete

Ds/Dc : Density ratio, steel to concrete

Note

For the calculation of section properties of Composite Section, concrete is converted into steel. The self-weight is computed as follows:

The Weight of Composite Section = Steel Weight + Concrete Weight

If Ds/Dc = 0, concrete weight is ignored and only steel weight is considered.

Ps : Poisso's ratio of steel

Pc : Poisson's ratio of concrete