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Important Note – These are descriptions to changes implemented in version 9.3 and may not reflect current program behaviour.
The following problems relating to bearing design have been corrected:
When the bearing width is set to a value other than the beam width, the program designed minimum required bearing lengths that become increasingly large from the leftmost support to the rightmost, even when the reactions at these supports are the same and the program should design the same minimum required bearing length at each support.
These required bearing lengths appear in the reactions and bearing table, and when bearing length is unknown, they affect the designed bearing length that is also shown in that table and in the beam drawing. They also affect the determination of design span if it is unknown and notch calculations. These problems have been corrected.
When point loads are located very near to the distance 'd' from the support, the program would exclude these loads in the design for Effect of loads applied near support (O86 5.5.7.3). However, these loads would be included when the program determined the minimum required bearing length for this design check. This could result in the minimum bearing length to be reported as longer than the specified bearing length, but the bearing check would report as passing.
The distance from the "d" point over which these loads were excluded was half the difference between the min. req’d bearing length and the actual bearing length.
For glulam beams as supporting members with unknown bearing length, the program was calculating a required bearing length for the supporting member that was too small due to problems in the iterative calculation for the supporting member's Kzcp factor. For designs where the supporting member bearing governs this resulted in the bearing design reporting a failed supporting member bearing design when it should have instead designed a slightly longer bearing length.
This problem could be circumvented by specifying a bearing length.
For SCL materials oriented as planks, the program did not use the weak axis Fcpy value for design, nor output it in the Modification Factors table of the Additional data. Because SCL has not been tested for oblique angles, for any angle between 0 and 90 the weak axis value now applies.
Furthermore, supporting members designated as sill plates now use weak axis Fcpy
When the member supported is a column, the program showed 0.69 for the supporting member wet service condition factor Ks in the Factors table of the Additional Data section of the Design Check Calculation Sheet, instead of 0.67 as per Table 5.4.2 of CSA O86-09. 0.69 is the Fc factor for parallel-to-grain compression, used for all the axial column checks. This is just a reporting issue that did not affect design
The following problems relating to O86-09 6.5.7.2.1 (a) and (b) for glulam shear design (O86-14 7.5.7.2) have been corrected. These are referred to as Case (a) and Case (b) in what follows.
The program was using 6.5.7.2.1 (b) for glulam shear design for beams smaller than two cubic metres in volume if Case (b) had a lower design ratio than Case (a) even if you had indicated via the design settings not to use Case (b). This has been corrected, and the program makes sure Case (a) is used when the setting for use of Case (b) is unchecked.
The program was also using Case (b) for columns when you had selected in the design settings to use Case (a), if it had the better design ratio. However, the option of using Case (a) for columns has been removed entirely (see Bug 3027, below).
In the Design Settings, the program allowed you to uncheck the use of 6.5.7.2.1 Case (b) for shear design of glulam columns so that the program was to use Case (a) for design. However, the design code stipulates that case (b) must be used for columns, and this option has been removed from the program. The output of case (a) has also been removed.
Because of bug 3028, described above) if the design ratio for Case (b) is better than Case (a), it is used regardless of whether you selected to use Case (a), so the incorrect use of (a) only occurred when it was advantageous when compared to (b).
Some users may have been misled by the Only when (b) > (a) terminology in the Design Settings into believing Case (b) is chosen for glulam shear when the resistance for b is greater, or the design response is greater (thus weaker). In fact, it is when the design response is smaller so this option is the stronger of the two methods. This setting has been changed to Only when (b) provides an advantage over (a).
The program shows "Wf = sum of all loads" in the CALCULATIONS section of the output for glulam shear design, even when indicating that Case (b) is the one that governs. Wf applies only to Case (a) so it has been removed for Case (b).
The Analysis vs. Design Table has been tidied up a little, by
The following problems relating to axial compression design for built-up columns using O86-09 5.5.6.4 have been corrected. Note that this is 6.5.6.4 in O86-14.
For axial compressive resistance of built-up columns, the program did not implement 5.5.6.4.5 for the case that the members aren't adequately connected, and you must always analyse a single ply and multiply by the number of plies, rather than using the full section width and factor for connection type.
The program now allows you to select Not adequately connected as the Connection type, and analyses using single ply for that choice. This connection choice appears in the material specification in the output reports.
When Not Adequately Connected is selected, the program forces the selection of the Design Setting for combined single-ply lateral stability analysis using O86 6.5.6.4, that is, not allowing the use of total width as in 5.5.4.2.1.
The program examines three cases when determining Pr : b-direction single-ply combined, b-direction full section factored, and d-direction. However, the program only output line of data. This was inconsistent with other checks like the multiple glulam shear checks and the multiple deflection checks. The equations are complicated in this case and it would be beneficial to see the calculations for each case.
The program now shows a line in the Analysis vs. Design for each of these cases, if applicable. For the b-direction, the program only shows the ratio for the more advantageous of the two cases, as 6.5.6.4.1 says you can use the greater of the two resistances from the methods, and if both were shown a failing design ratio could appear for the lesser of the two.
In the CALCULATIONS section, the program indicates which of the cases governs, outputs the slenderness ratio Cc for all three cases, and gives the connection factor used from 6.5.6.4.2-4.
When determining the combined strength Pr of the plies taken as individual pieces according to 5.5.6.4.1, the program used the full area A when determining the strength for a single ply, then multiplied that strength by the number of plies, effectively multiplying by the number of plies twice.
Since the KC factor is ordinarily quite low for single plies, using the full member width approach factored according to connection type (5.5.6.4.2-4) is often greater than the single ply value even when multiplied by the number of plies twice, so this was an issue only for shorter unsupported lengths, roughly 4 feet or less.
When determining the combined strength Pr of the plies taken as individual pieces according to 5.5.6.4.1, the program never considered the 1/50 limit on slenderness ratio from 5.5.6.2 when evaluating the single plies. This has been corrected, and the combined single ply option not evaluated if the slenderness ratio more than 1/50. Note that single ply analysis was unlikely to govern if there was such a high slenderness ratio.
The following problems with calculation of the lateral stability factor KL using O86-09 5.5.4.2 and 6.5.6.4 have been corrected. Note that these are 6.5.4.2 and 7.5.6.4 in O86-14, respectively. The design code references below refer to the 09 code in which the problems appeared, but have been corrected for O86-14 as well.
When using full member width to determine the lateral stability of built-up members, the program was using 4.0:1 as the highest b/d ratio for which KL = 1, from -09 5.5.4.2.1. However, the program should have been using the ratio 2.5:1 from 6.5.6.3.1, because 5.5.4.2.2 indicates that this clause should be used for built-up members.
This value is used only when the Design Setting is set to using full member width for built-up lateral stability calculations. If single ply is used, the 4:1 ratio is used using the single ply dimensions.
As the program now allows you to select Not Adequately Connected as the built-up column connection type (Bug 3009, above), when you do so, the program forces the selection of the Design Setting for combined single ply lateral stability analysis using O86 6.5.6.4, that is, not allowing the use of total width as in 5.5.4.2.1.
When the Design Settings for conditions satisfying KL = 1 and for use of single ply width for KL are both set, the program used the full member width to determine whether the d/b ratio is greater than 9, so that KL must be calculated regardless of the KL = 1 setting , as per 7.5.4.2.
The program now uses the single ply width to determine this ratio if single ply is set to be used for KL calculations in the Design Settings.
You could simultaneously specify that an interior support or supports are not laterally restrained, and the Design Setting that the Conditions for KL = 1 are true, and in this case the program set KL = 1 without calculating. However, O86 6.5.4.2.1 says that in order to assume KL = 1, one of the conditions required is that the member is laterally supported at all points of bearing.
The program now overrides the KL = 1 setting when any interior support is not set, similar to the override for d/b rations greater than 9 . The note that appears by the lateral support input in beam view when KL = 1 has been modified accordingly.
Note that the program now allows users to specify that interior supports are not laterally restrained (see Feature 212, Version 9.1, Item 1 below), despite the condition in 6.5.4.2.1 about lateral support at points of bearing. However, this is only allowable on the assumption that the bending moment value is penalized by a longer unrestrained length in the calculation of KL, hence the override of the KL = 1 setting.
The following problems affected the lines in the Calculations section of the Additional Data output that give the values for unsupported length ℓu, effective length ℓe, slenderness ratio CB from O86-09 6.5.6.4, and the design settings that affect this calculation. These were reporting problems only, and did not affect design. They have been corrected.
The program was showing identical lines for positive and negative moment for columns if such moments existed. As we assume both edges of a column are supported the same way, this was unnecessary, and one of the lines has been removed. In the case that there is only a positive moment, the "(+)" symbol has been removed.
The program no longer outputs a this line when KL = 1.0 because the ratio d/b is less than 4.0 for sawn lumber (O86 09 5.5.4.2.1) or 2.5 for glulam (6.5.6.3.1) or built-up members (5.5.4.2.2). Previously it was showing values it calculated but did not use.
The phrase output at the end of the line indicating the Design Setting for Unsupported length ends at points of zero moment had the following problems:
The value for the lateral stability factor KL was not appearing in the Factors table of the Additional Data output for columns; instead a dash was appearing. Note that columns usually have a KL factor of 1.0 due to their squarish shape and low d/b ratio, so in most cases 1.0 now appears instead of the dash.
When determining whether to output a design note indicating the condition the program must satisfy in 5.5.4.2.1 under the Design Setting specifying that KL = 1 is to be used, for built-up members the program always used the width of a single ply. However, when deciding which of the conditions to put in the note, the program used the full width of the member. As a result, the note was rarely output.
The program now uses single ply for both if the Design setting says single ply is to be used for slenderness factor, and full member width if the Design setting says it should be full member width.
When the Design setting is set to use single ply width for lateral stability calculations, the phase about required fastening has been removed from the Design Note for built-up members.
The design setting to decide whether full member width or single ply width is to be used for lateral stability calculations of built-up members referred only to the slenderness ratio and associated clause 6.5.6.4.3. However, the setting also applies to the b/d ratio used to determine whether the lateral stability factor KL = 1 using 5.5.4.2, and the wording of the Design setting has been modified to reflect this.
The note that is meant to indicate the Design Setting that KL is to be calculated as per O86 6.5.6.4 for sawn and SCL has been removed when the design ratio is less than 2.5 for glulam and built-up members and less than 4 for sawn and SCL. In these cases 6.5.6.4 is not actually used, as per 5.5.4.2.1.
For sawn lumber and SCL, the note giving the restraint conditions at bearing supports from the first paragraph of 5.5.4.2.1 is now given in addition to the note indicating the Design Setting which says KL is calculated as per O86 6.5.6.4. Previously these notes were mutually exclusive, however, the support conditions in (a) to (f) are in addition to the first paragraph, not instead of it.
(The "Alternatively" in 5.5.4.2.1 is indented and therefore is alternative to (a) to (f), not alternative to first paragraph. For glulam, 6.5.6.4 says "when no additional support…" and 6.5.6.3.1. requires restraint at bearing even when KL is calculated, so one can assume the same is true for sawn lumber.)
The note about lateral restraint required at points of bearing could contradict the recently added Design Setting for which we allow interior supports not to be supported. In this case, an additional note is added: This beam is restrained at end supports only.
A separate design criterion for shear at a notch from CSA O86-09 5.5.5.3 is shown in the Force vs. Resistance table, but there was no corresponding line in the Factors table of the Additional Data. As a result, the ff = 0.50 MPa value and the KSf = 0.7 service condition factor for 5.5.5.3 were not shown in the output, and the 0.87 KSv service factor, the KZ size factor and the fv value from 5.5.5.2 were shown even if the notch provision governed rather than the values shown.
This has been corrected, and separate lines for Ff from 5.5.5.3 and Fv from 5.5.5.2 are shown in the table.
The program only performs joist vibration under certain circumstances for which NBC A-9.23.4.2 (2) is valid, but this is was not apparent to users of the program. The program now disables vibration controls and places an explanatory note in the Vibration line of the Analysis vs. Design table if
Starting with version 10.2, for built up members loaded on the weak axis (d-face), the program used the sum of the thicknesses of the plies as the depth used for determination of section modulus Sy in the expression for bending moment resistance Mry from O86 5.5.4.1 and 6.5.6.5.1, and for the moment of inertia Iy in the stiffness EI used in deflection calculations. However, this assumes that the plies are rigidly connected, as with glue. As full composite action cannot be achieved by fastening members with bolts or nails, the program once again uses the single ply thickness to calculate S and I for each ply, then sum these values for a composite S and I to determine Mr and EI, respectively This results in a lower bending resistance and greater deflections than the program had been calculating.
For a beam with a left end cantilever and a notch at the far right support, the program would crash when a design is run. This has been corrected
The program no longer outputs the volume of steel beams in the materials specification, as it is not relevant to W-section steel beams.
In the Critical Load Combinations section of the Additional Data, the program was showing a bearing load combination at the free end of a cantilever. This has been removed.
There design note describing the construction of built up members broke part way through one line and continued on the next. This has been corrected.