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This module allows you to design concrete shear walls of several physical layouts:

 

1- Multi-Story wall with no openings but with up to five levels of differing length, height and thickness.

 

2- Single story wall with openings.

 

Soon to be added will be a concrete solid wall with cast in end columns and also "special boundary elements" per ACI.

 

Also to be added will be masonry and wood shear walls with similar capabilities.

 

 

Walls with Openings

The ability to specify openings in a rectangular wall is allowed for the Wall with Openings wall type. You have the ability to specify opening locations anywhere you like. The module analyzes the wall and creates piers that divide the wall into rectangular elements. The Sketch tab provides a drawing of the piers that the module has determined from the input data. See below:

 

 

The analysis starts at the top of the wall and moves downwards. Applied loads and wall self weight (if selected) are determined in each pier and the forces and moments are calculated.

 

The module can distribute loads from a single pier above to multiple piers below (or multiple piers at the same level to a single connecting pier) either by proportional rigidity of the piers or by tributary length. The Results tab provides you with a good view of how the load distribution progresses. In the screen capture below note that for the load combination each pier is listed, the proportional shear value for a pier and the applied, self weight and loads from above to that pier are shown.

 

 

In the two screen captures above take a look at P4. It will transfer load to piers P6 and P7. Note that the table shows that P6 will take 10.1% of the shear load and P7 will take 89.9% of the shear load. Those values were arrived at from the relative rigidities of P6 and P7. When considering the distribution of vertical loads to piers P6 and P7 in the image above, the load is distributed in proportion to the tributary width from the pier above. For vertical loads, the program arrives at a distribution of 30% to P6 and 70% to P7.

 

General Tab - Multi Story Solid

If you wish to design a wall up to five levels high but without openings, click the [Multi-Story Solid] button. The tab will change to display the entries shown below:

 

 

Height specifies the total height of the wall. On the next tab you can divide that total height into up to five different wall portions.

 

Ec is the bending modulus of elasticity and Ev is the shear modulus of elasticity.

 

 

General Tab - Wall with Openings

When you want to design a solid wall with openings click the [Wall w/ Openings] button:

 

 

Length, Height & Thickness define the overall wall dimensions. The length you enter is used for the length of the bottom-most portion of the wall. Within those dimensions you will specify the openings on the next tab labeled Openings.

 

SDS is used to calculate the in-plane portion of the wall weight to be applied as a seismic load.

 

Ec is the bending modulus of elasticity, and Ev is the shear modulus of elasticity.

 

The Default Rebar Size & Spacing are used in the calculated bar requirements when the reinforcing due to shear is less than code minimums.

 

 

Multi-Story Wall Tab

This tab is where you specify the distinct wall levels for the multi-story wall.

 

 

Analysis Height locates the bottom edge of the wall section and is where the maximum shear and bending stress will be calculated.

 

Wall Offset is the distance that this wall section is offset from the left-most edge of the bottom-most wall section.

 

Wall Length is the length of the wall section. Maximum length is the overall wall length - offset.

 

Wall thickness is the thickness of this wall section.

 

Effective Depth locates the tension rebar in the panel, and is used to calculate "shear depth" for calculation of actual shear stresses

 

 

 

Checkboxes

 

Analysis Height

This is the user-defined height at which the analysis of a particular wall section will be performed. All moments, shears, and vertical loads at this height will be calculated using all applied lateral and vertical loads and the wall self weight above this point. The other wall data items specified in the same column will be used between this analysis height and the next higher level indicated in the column to the right.

 

ALWAYS WORK WITH THE HIGHER ANALYSIS HEIGHT IN THE COLUMN TO THE RIGHT OF A LOWER HEIGHT. This is needed due to the manner in which the module calculates the heights by comparing heights of adjacent sections.

 

Total Wall Height

Enter the total height of the wall. This height is used by the module to determine the total height that the topmost Analysis Height wall section should extend to for determining the weight of that uppermost section.

 

Wall Offset

Please refer to the diagram to further understand this item. Because this module can be used with a walls that have their length changes with height, you must enter the offset from the bottom wall section to the LEFT EDGE of the wall section. This enables the module to calculate the actual X-Distance to the center of gravity of the wall.

 

Wall Length

Enter the length to be used in the analysis of the particular wall section. Please note that if the Wall length + Offset is greater than the Wall Length + Offset for the level below, this indicates that the section OVERHANGS the section below it. This is not allowed.

 

Wall Thickness

Enter the thickness to be used in the analysis of a particular wall section. This thickness will be used only between the Analysis Height for that section up to the analysis of the next higher section (or Total Wall Height if it is the highest section).

 

d:Effective Depth

The module considers the effective shear length of the wall to be 0.8 * wall length. If you leave this entry blank, it will be filled in for you automatically.

 

 

 

Openings Tab - Perforated Wall

This tab allows you to enter the wall openings.

 

Openings are defined by the distance of the lower-left corner of the opening from the lower-left corner of the wall.

Opening width and height are measured upwards and to the right.

 

 

Use the [Add] and [Edit] buttons to specify the dimensions of the opening. Clicking either button displays this window:

 

 

 

Loads Tab - Multi-Story Wall

This main tab has four sub-tabs that allow you to enter four types of loads.

 

Vertical loads can be of dead, live, roof live and snow types.

 

Lateral loads can be of seismic and wind types.

 

Add wall weight to dead loads will tell the module to calculate the weight of the wall above each analysis height and include it in the vertical dead loads to calculate applied axial stress. It also is used for footing design when that option is selected.

 

Add wall weight as SEISMIC load will calculate the wall self weight, apply the lateral weight seismic factor and "E" load combination factor. The resulting load will be applied at the wall center to calculate shear and overturning due to that portion of the wall. This is used for values at the analysis height, for the effect of that level's seismic weight on the levels below, and for footing overturning and sliding calculations.

 

Vertical Point Loads

Use this tab to apply point loads to the wall. You can specify an "X" and "Y" distance from the lower-left corner of the lower wall so that the load can be located anywhere on the defined walls.

 

 

 

Use the [Add] and [Edit] buttons to change the values of applied loads. Clicking either button displays this window:

 

 

 

Vertical Uniform Loads

Use this tab to apply uniform loads to the wall. You can specify a "Y" distance from the bottom of the lower wall so that the load can be located at any height.

 

 

 

Use the [Add] and [Edit] buttons to change the values of applied loads. Clicking either button displays this window:

 

 

 

Lateral Point Loads

Use this tab to apply point lateral loads to the wall. You can specify a "Y" distance from the bottom of the lower wall so that the load can be located at any height.

 

 

 

Use the [Add] and [Edit] buttons to change the values of applied loads. Clicking either button displays this window:

 

 

 

Lateral Uniform Loads

 Use this tab to apply uniform lateral loads to the wall. You can specify a Start and End location to define the extent of the lateral load.

 

 

 

Use the [Add] and [Edit] buttons to change the values of applied loads. Clicking either button displays this window:

 

 

 

Loads Tab - Perforated Wall

This main tab has four sub-tabs that allow you to enter four types of loads. The module will correctly apply the loads you specify to the portions of wall to which they are applied. Any loads that exist within an opening will be ignored.

 

Vertical loads can be of dead, live, roof live and snow types.

 

Lateral loads can be of seismic and wind types.

 

Add wall weight to dead loads will tell the module to calculate the weight of the wall above each analysis height and include it in the vertical dead loads to calculate applied axial stress. It also is used for footing design then that option is selected.

 

Add wall weight as SEISMIC load will calculate the wall self weight, apply the lateral weight seismic factor and "E" load combination factor. The resulting load will be applied at the wall center to calculate shear and overturning due to that portion of the wall. This is used for values at the analysis height, for the effect for that levels seismic weight on the levels below, and for footing overturning and sliding calculations.

 

 

Vertical Point Loads

 

Vertical Uniform Loads

 

Lateral Point Loads

 

Lateral Uniform Loads

 

 

Footing Tab

You also have the option to specify a footing under a shear wall by selecting the Specify a Footing checkbox.

The dimensions of the footing are specified using Distance @ Left and Distance @ Right.

 

Distance @ Left is the distance that the footing projects past the left edge of the wall (meaning the lower wall level for a multi-story type wall).

Distance @ Right  is the distance that the footing projects past the right edge of the wall (meaning the lower wall level for a multi-story type wall).

 

Rebar is assumed to exist only at the bottom of the footing to resist tensile forces from the vertical loads and increased pressure due to overturning forces. Tension in the top of the footing in cases where no upward soil pressure exists and the footing weight creates a downward net force IS IGNORED.

 

 

 

Load Combination Tab

The typical load combination tab for strength design of concrete is provided.

 

 

 

Multi-Story Wall Summary - Stresses Tab

For multi-story walls the module provides a summary of each level.

 

In the top portion you will see the calculated shear, moment and axial loads at the analysis height you have specified. These values are due to wall self weight and applied vertical and lateral loads from that analysis height and above.

 

In the bottom portion of the screen, the unit shear stresses, shear steel required and end reinforcing for bending tension in that wall section are reported. All calculations are per ACI.

 

 

 

Multi-Story Wall Summary - Forces Tab

This tab provides the detailed force values for each wall level and for each load combination.

 

Pier Summary Tab - Wall with Openings

When a wall with openings is selected a list of resulting information for each rectangular analysis portion is provided.

This table is the condensed results of the Pier Forces tab and shows only the governing load combination values for shear load and reinforcing for each pier.

 

 

Pier Forces Tab - Wall with Openings

This tab shows the detailed analysis information for each pier. Because piers are numbers from top to bottom of the wall you can roughly see how the loads are transferred downwards.

 

Shear % values are the calculated portion of shear that each pier will receive from the level above based on the stiffness of that pier and others acting in parallel with it.

Applied values are the loads that the user has entered that are found to be applicable to that pier given their dimensioned locations.

Self Weight values are the calculated self weight of the pier if the user has selected to have the module auto calculate them.

From Above values are what is applied to that pier from the pier connected to the top of that pier.

Vertical % values are the calculated portion of vertical load that each pier will receive from the pier attached above. This % is based on tributary lengths.

 

 

 

Pier Details Tab - Wall with Openings

This tab is a simple summary of the module-generated piers and a small sketch of each.

 

 

Footing & Stability Tab

This tab provides the calculated service and factored load soil pressure, one-way shear and bending at the end of the wall.

 

 

Sketch Tab - Multi-Story Solid

 

 

Sketch Tab - Wall with Openings