Joist errors
The "Errors" option, within the "Joists" menu on the "Results" tab, allows you to view the errors obtained following the analysis for each of the joists.
Once you have clicked on this option, any joists with deflection or shear errors, or any other issues, will be highlighted in red.
For more information about the specific error, left-click on the joist and read the message that appears. If the joist group has no errors, the text "No errors" will appear.
The "Previous" and "Next" buttons in the dialogue box allow you to navigate between the other floor joists on the floor that contain errors.
Description and solutions for joist errors
Below is a detailed list of the various errors that may occur in joists, along with recommended remedies:
| Error | Description | Solution |
| Dead load instant. deflection limit | The deflection limit has been exceeded. | Increase the floor slab depth, place a double joist or change the panel layout. |
| Live load instant. deflection limit | The deflection limit has been exceeded. | Increase the floor slab depth, place a double joist or change the panel layout. |
| Total instant. deflection limit | The deflection limit has been exceeded. | Increase the floor slab depth, place a double joist or change the panel layout. |
| Total long-term deflection limit | The deflection limit has been exceeded. | Increase the floor slab depth, place a double joist or change the panel layout. |
| Active deflection limit | The deflection limit has been exceeded. | Increase the floor slab depth, place a double joist or change the panel layout. |
| Positive moment at joist support | There is only positive moment at the support | There is only one positive moment at the support |
| Insufficient floor slab depth to resist the flexure | The top reinforcement works in compression. | Increase the floor slab depth or place a double joist. |
| The width of the rib does not allow for the reinforcement due to compatibility problems with the bar spacing and cover | The bottom reinforcement does not fit in the in situ rib width. | Increase the floor slab depth or the thickness of the rib. |
| No joist is found to cover the maximum positive moment | The maximum moment exceeds the maximum defined in the manufacturer's joist sheet. | Depending on the case, increase the stiffness of the beam where the joist bears, pin the panel at its edges, or study the continuity of the bottom reinforcement. |
| There are no sections in the series that do not fail for this floor slab and form geometry | This occurs in steel joists probably due to having inserted an excessive rib spacing with respect to the width of the form, in such a way that it is not possible to support it on the flanges of the section. | Place the appropriate rib spacing for the form or vice versa. |
| No section has been found in the series that does not fail for the calculated forces | The forces exceed the maximum that can be resisted by the joists of the series. | Change the section series. |
| The resistance checks fail | One or more resistance checks fail. | Review all the checks carried out using the "Check" option and make any necessary changes. |
| The fire resistance checks fail | One or more fire resistance checks fail. | Review all the checks carried out using the "Check" option and make any necessary changes. |
| The depth of the section is greater than the maximum allowable depth | The depth of the section is greater than the maximum allowable depth defined in the data of the floor slab. | Increase the floor slab depth. |
| No reinforcement has been found that meets the geometric and mechanical minimums | There is no reinforcement in the in situ joist reinforcement table that will meet the cited minimum ratios. | Edit the reinforcement table as required. |
| There is no entry in the bottom reinforcement table meeting the requirement that the partial additional reinforcement must be smaller than the rib length | A base reinforcement has been assigned to the in situ ribs, and the additional reinforcement calculated is longer than the joist. This is not allowed. | Increase the base reinforcement ratio, the rib width, or the floor slab depth. |
| There are no joists that do not fail when their bottom reinforcement is extended to their ends | The length of the calculated additional reinforcement is greater than that of the joist. This is not allowed. | increase the floor slab depth or place a double joist |
| There are no joists with sufficient base reinforcement to allow for the partial additional reinforcement to have a length smaller than that of the joist's | Trying to find sufficient base reinforcement to allow for the additional reinforcement to have a length smaller than the joist's. | Increase the floor slab depth or place a double joist |
| Insufficient section for negative moment | The compressed zone does not resist the stresses produced by the negative moment. Not even infilling will resolve this problem. | Increase the floor slab depth. |
| Excessive negative moment | The forces exceed the maximum that can be resisted by the manufacturer's joist sheet. The value of the moment is shown. | Increase the floor slab depth or place a double joist |
| Required top reinforcement area | Increase the floor slab depth or place a double joist | Increase the floor slab depth or place a double joist |
| Top reinforcement outside table rang | The top reinforcement defined in the tables is not sufficient, but the program calculates the necessary reinforcement anyway. | We recommend increasing the depth of the floor slab or installing double joists rather than modifying the reinforcement table. |
| Infill greater than twice the depth | To avoid the bottom reinforcement working in compression, since the concrete is at its limit, an infill is provided, but the program emits a warning when the infill exceeds this length. | Increase the floor slab depth. |
| Infill greater than 20% of the clear span | To avoid the bottom reinforcement working in compression, since the concrete is at its limit, an infill is provided, but the program emits a warning when the infill exceeds this length. | Increase the floor slab depth. |
| Fixed or continuous ends in this type of joists are not designed | Although steel joists are automatically pinned at the edges, in the case of cantilevered joists, the program gives continuity to the interior panel to achieve local equilibrium. The negative moment is not designed for. | Modify the defined conditions or the type of floor slab. |
| The calculated shear cannot be resisted | Increase the floor slab depth or place a double joist | increase the floor slab depth or place a double joist |
| Top reinforcement outside table range | The lateral cover is greater than the width of the support beam. | Increase the floor slab depth or place a double joist |
