Reactions Diagram

The Reactions Diagram is used throughout the modern platform to plot all the reactions for each support in a member. It uses diagram widget type "beamReactions".

Implementation

{
    "type": "sheetTemplateWidgets",
    "attributes": {
        "type": "diagram",
        "diagram": [
            {
                "type": "beamReactions"
            }
        ],
        "equation": [
            {
                "result": "{PARAMETERS}",
                "condition": "CONDITIONS"
            }
        ],
        "referenceId": "reactions_diagram"
    }
}

Plot Parameters

Parameter	Format	Default	Description
L	number	-	The length of the member
dispR	array of strings	`[]`	Example: `["UltMax", "UltMin", "G", "Q"]`. A list of the load types to plot in the reactions diagram. All load types, along with “Ult”, “UltMax”, and “UltMin” are available
dispTooltip	array of strings	`dispR`	A list of the load types to display in the tooltip
allR	array of dicts	`[]`	Example: `remote.plot.allR`. All of the reactions data from the solver
lenConvert	number	`1`	Conversion factor for length
lenUnit	string	`"m"`	Unit for lengths
bearingUnit	string	`"mm"`	Unit for length of bearing, if different
plUnit	string	`"kN"`	(defaults to `"kN"`) Unit for point reactions
mlUnit	string	`"kNm"`	(defaults to `"kNm"`) Unit for moment reactions
column	boolean	`false`	(defaults to `false`) Plots the reactions on a vertical axis and adjusts other text locations appropriately
scaleArrows	boolean	`true`	(defaults to `true`) Whether or not to scale the reaction arrows according to the absolute value of the ultimate maximum reactions
upstreamReferenceId	string	-	If you want to display a button to link the reaction to other sheets as an upstream sheet

Reaction Data Format

The allR parameter contains comprehensive reaction data from the solver:

allR: [
    {
        x: 0,                    // Support location
        supportType: "fixed",    // Type of support
        reactions: {
            "G": {               // Dead load reactions
                Ry: 45.2,        // Vertical reaction (kN)
                Rx: 0,           // Horizontal reaction (kN) 
                Mz: 0            // Moment reaction (kNm)
            },
            "Q": {               // Live load reactions
                Ry: 30.8,
                Rx: 0,
                Mz: 0
            },
            "UltMax": {          // Ultimate maximum
                Ry: 98.5,
                Rx: 0,
                Mz: 0
            },
            "UltMin": {          // Ultimate minimum
                Ry: 76.0,
                Rx: 0,
                Mz: 0
            }
        }
    },
    // ... more supports
]

Load Type Display

Use dispR to control which load combinations are displayed:

{
    dispR: ["G", "Q", "UltMax", "UltMin"],  // Show dead, live, and ultimate reactions
    dispTooltip: ["G", "Q", "W", "UltMax", "UltMin"]  // Include wind in tooltips
}

Common Load Type Codes

G: Dead loads (permanent loads)
Q: Live loads (imposed loads)
W: Wind loads
E: Earthquake loads
S: Snow loads
Ult: Ultimate load combination
UltMax: Maximum ultimate combination
UltMin: Minimum ultimate combination
SLS: Serviceability limit state

Example Implementation

{
    "type": "sheetTemplateWidgets",
    "attributes": {
        "type": "diagram",
        "diagram": [
            {
                "type": "beamReactions"
            }
        ],
        "equation": [
            {
                "result": "{
                    L: beam_length,
                    allR: remote.plot.allR,
                    dispR: [\"G\", \"Q\", \"UltMax\"],
                    dispTooltip: [\"G\", \"Q\", \"W\", \"UltMax\", \"UltMin\"],
                    lenUnit: \"m\",
                    plUnit: \"kN\",
                    mlUnit: \"kNm\",
                    lenConvert: 0.001,
                    scaleArrows: true
                }",
                "condition": "@default"
            }
        ],
        "referenceId": "beam_reactions",
        "label": "Support Reactions",
        "showInSuperSummary": true
    }
}

Column Mode

For vertical members, set column: true:

{
    "result": "{
        L: column_height,
        allR: column_reactions,
        dispR: [\"G\", \"Q\", \"UltMax\"],
        column: true,
        lenUnit: \"m\",
        plUnit: \"kN\"
    }"
}

Upstream Linking

The upstreamReferenceId parameter enables linking reactions to upstream sheets:

{
    "result": "{
        // ... other parameters
        upstreamReferenceId: \"linkMembersY\"
    }"
}

Tutorial: Upstream Linking VideoIf you want to display a button to link the reaction to other sheets as an upstream sheet, the value should be the type of reaction that the diagram represents such as linkMembersY.Clicking the button will open a modal with options of which sheets you can link to the reaction. Compatible sheets are those with templates where this upstreamReferenceId value is in the importReferenceIds array of the template.

Upstream Reference Setup

In the target template’s header, include the reference ID in importReferenceIds:

{
    "importReferenceIds": [
        "linkDL",
        "linkLine", 
        "linkMembers"
    ]
}

Arrow Scaling

Control reaction arrow scaling with scaleArrows:

{
    scaleArrows: true,   // Scale arrows based on ultimate maximum reactions
    scaleArrows: false   // Use uniform arrow sizes
}

Setting scaleArrows: true helps visualize the relative magnitude of reactions, making it easier to identify critical supports.

Best Practices

Load Selection: Choose appropriate load types for display based on design requirements
Units: Ensure consistent units for all reaction components
Tooltips: Include more load types in tooltips than displayed for comprehensive information
Linking: Use upstream linking for templates that feed loads to other calculations
Scaling: Use arrow scaling to help visualize reaction magnitudes

Only one upstreamReferenceId can currently be passed per diagram. If you need multiple linking options, consider using separate diagrams or custom implementations.

Integration with Beam Solvers

Reactions diagrams work seamlessly with beam solver results:

{
    "type": "sheetTemplateWidgets",
    "attributes": {
        "type": "remote",
        "solver": "beam",
        "equation": [
            {
                "condition": "@default", 
                "result": "{
                    L: beam_length,
                    r: support_data,
                    PL: point_loads,
                    DL: distributed_loads,
                    loadCombinations: load_combinations
                }"
            }
        ],
        "referenceId": "beam_analysis"
    }
}

The solver automatically generates the allR data structure with reactions for all specified load combinations.

Guides

Analysis Calculators

Design Calculators

Calcs Builder

Implementation

Plot Parameters

Reaction Data Format

Load Type Display

Example Implementation

Column Mode

Upstream Linking

Upstream Reference Setup

Arrow Scaling

Best Practices

Integration with Beam Solvers

​Implementation

​Plot Parameters

​Reaction Data Format

​Load Type Display

​Example Implementation

​Column Mode

​Upstream Linking

​Upstream Reference Setup

​Arrow Scaling

​Best Practices

​Integration with Beam Solvers

Implementation

Plot Parameters

Reaction Data Format

Load Type Display

Example Implementation

Column Mode

Upstream Linking

Upstream Reference Setup

Arrow Scaling

Best Practices

Integration with Beam Solvers