Only members specified as "Lateral" members in RAM Modeler are included in the frame analysis. The only exception is that gravity members (columns and walls) that support a two-way deck can be also included analysis. These gravity members are only used for gravity load cases and they are removed for lateral load cases (seismic and wind). This optional feature is provided in Story Diaphragm dialog.

The interaction between gravity and frame members is not accounted for except the loads from gravity members supported by frame members are considered, gravity beams provide lateral bracing to the Frame members, and loads on transverse gravity columns and walls are applied to lateral members for models with semirigid diaphragms.

Frame members must support frame members. For example, a gravity column cannot support a frame beam, and a gravity beam cannot support a frame column or wall. The Modeler DataCheck will indicate an error for this condition.

Some levels, such as a roof penthouse or mechanical platform, have minor lateral systems that are not part of the main structural lateral system. It is permissible to model these levels without specifying any of the members as frame members. By modeling them as gravity members only, their contribution to the gravity loads and masses of the building is accounted for without unnecessarily complicating the frame analysis. If the lateral system of these levels is included in the model, then all of their frame members must be supported by other frame members.

Sizes must be assigned to the frame members. RAM Frame does not automatically select optimum sizes. Sizes may be assigned to frame members either in the RAM Modeler, RAM Concrete or RAM Frame. Alternatively, the RAM Steel Beam and Column Design programs can automatically select preliminary sizes for the steel beams and columns. In these modules, the lateral members will be designed for the gravity loads they carry, assuming pinned end conditions.

Once a size is assigned to a Lateral member, either by the user or by the design modules, it becomes a User Size, i.e. it must be cleared using the Clear Size command in order for the gravity design programs to automatically redesign the section. When no size is assigned to a frame member, the Modeler DataCheck will indicate an error and the analysis will not run.

RAM Frame automatically meshes walls, considering any openings inside walls. Since openings are automatically accounted for during meshing process, it is no longer necessary to model "dummy" levels at the top and bottom of openings. It is also not necessary to break wall panels into small panels where shorter walls above sits on a longer wall below, nor when a frame column or beam frames into a wall. Such conditions are automatically handled by the program. The user can control the mesh quality (see Modeling Shear Walls). In some situations the program may not produce as regular of a mesh as desired; in that case the mesh can be further controlled by modeling long walls as a series of shorter panels. This is rarely necessary. It should be noted that the wall mesh density (either coarse or fine mesh) may have an influence on the analysis results.

When two lateral walls come together to form a T - shape, the wall that forms the "flange" of the "T" must be modeled as two separate walls. It is necessary to have a node line in the wall where the "stem" of the "T" frames in. The program does not automatically deal with this condition. The Modeler DataCheck will indicate an error when the condition is modeled incorrectly.

Member offset can be defined in the modeler and they are automatically included in analysis in RAM Frame. It should be noted that one can define member offset between beams, between beam and column, between beam and wall, between column and wall and between columns (member offset between walls not supported).

Lateral hanging columns are included in the analytical model. They are similar to standard columns except that gravity load distribution is carried out in such a way that a hanging column transfers gravity loads up to the member or diaphragm it is hanging from.

Other than calculating the floor loads that load a wall at a particular level and simply transferring the loads vertically down to supporting beams or walls, no analysis is performed on gravity walls by any of the RAM Structural System modules. Consider including all walls as part of the lateral system and performing a frame analysis to get the distributed force results for multi-level wall systems.

Multiple diaphragms per story can be defined in the Modeler. RAM Frame recognizes such configurations and calculates mass properties of each diaphragm and uses this information during analysis.

Diaphragms can be identified as Rigid, Semirigid, Pseudo-Flexible and Flexible\None. Diaphragm type is defined in Story Diaphragm dialog invoked by Criteria-Diaphragm command. Diaphragm provides more information for diaphragm types. Also in Semirigid Floor Diaphragms more information about analysis with Semirigid diaphragms is provided.

Models with one-way slabs or two-way slabs or both can be defined and analyzed in the program. Regarding one-way slabs, the program calculates effects of gravity loads based on tributary area method and apply these loads on lateral members located inside one-way slab areas. On the other hand, models with two-way slabs (for instance, concrete flat slabs or flat plate floors) are handled in such a way that gravity loads on these slabs are directly applied to diaphragms and thus, they are transferred to other members through diaphragm bending action (i.e., two-way load distribution). Also for semirigid diaphragms, lateral loads are transferred to lateral load resisting members through diaphragm in-plane stiffness. It should be noted that a diaphragm is meshed directly if any two-way slabs is found inside the diaphragm. Also, any diaphragm designated as semirigid (either containing one-way or two-way deck) is also meshed.

In models where a diaphragm is to be specified as Rigid, the extent of the rigid diaphragm is defined by the slab edge, opening edges, and penetrations. All columns, beams and walls inside the slab boundary are analyzed by RAM Frame as "connected" to the diaphragm; those outside of the slab boundary are analyzed as "disconnected" from the diaphragm. Members enclosed by an opening or penetration are "disconnected" from the diaphragm, by default. The user can "connect" or "disconnect" a member from the diaphragm by using the Assign – Nodes – Diaphragm Connection command.

Frame numbers can be assigned to each frame member. This is not necessary for analysis purposes, but is provided as a convenience. Report outputs are organized by frame number, and certain View and Print commands can be specified by frame numbers. Frame numbers can be assigned in any way desired; members within a contiguous frame do not need to be assigned the same frame number. For example, columns could be given a different frame number than the beams, or beams could be grouped by assigning different frame numbers to different groups.

Modeling of coupling beams for shear walls can be carried out by using either frame (beam) elements or shell (wall) elements. For deep coupling beams, it is recommended to use shell elements, which captures shear dominated behavior very well. For slender coupling beams, a beam element may be sufficient to capture bending action. On the other hand, for moderately deep coupling beams, using beam element alone may not be sufficient to capture both shear and bending actions. In these cases, it is recommended to use "Include Rigid Link at Fixed Beam-to-Wall Locations" option. If this option is selected, the program internally provides a rigid link at the location where a coupling beam frames into a shear wall. This kind of modeling provides a better load transfer between the beam and the wall. It should be noted that the rigid link is only functionally for the load transfer between the wall and the beam (otherwise, it does not alter stiffness of the wall or the beam).