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# Can multiple elements be assigned to a single member for accuracy of results?

## Question

Can multiple elements be assigned to a single member for accuracy of results?

You can assign multiple elements as a single member (single member) using the 'Member Assignment' function for accuracy of the results.

'Member Assignment' is a function that allows you to assign multiple elements (beam, truss, or frame elements) to a single member during the modeling process. This enables you to design the structure as a single member for analysis purposes even if it is divided into several elements.

When a single member is modeled as multiple line elements, assigning the Member and performing design and strength verification, the results for the single member can be output regardless of the number of divided elements. By designating the member, the design variables can be automatically calculated in the program for the designated member, making it easier to set the design variables for automatic design.

### Precautions

1) In case multiple elements are assigned as a single member, the element number is specified as the element number in Local Direction I of the elements that make up the Member, and that element becomes the representative element of the member. The design variables of the member are only applied when entered for the representative element of the member.

2) If the elements of a member have different material, cross-section, and local direction, they cannot be assigned as a single member.

3) When applying the function to assign a member of multiple elements and calculate the design variables automatically, the program calculates the design variables such as Effective Length Factor (K), Equivalent Moment Correction Factor (Cm), and Unbraced Length (L, Lb) by considering the connection state of the member. Therefore, it is possible to obtain accurate results.

4) Among the design variables, the values (Effective Length Factor (K), Equivalent Moment Correction Factor (Cm), Moment Magnifier (B1 / δb, B2 / δs), and Limiting Slenderness Ratio) are used from the representative element. In case of Unbraced Length (L, Lb), the values from each element are used.

For example, when designing a subway station and performing a cross-sectional review of a wall, the wall can be designed by assigning it as a single member, even if it is divided into multiple line elements.

As shown in the figure below, even if the wall is divided into six line elements, by using the 'Member Assignment' to assign it as a single member, it can be reviewed as a single cross section of the wall when conducting a cross-sectional review through UMD.

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