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March 28, 2005 - Concise Beam version 4.34 is now available for download

Version 4.34 includes the following changes;

• The flexure design reports now summarize the maximum positive and negative critical moments along the beam as well as summarizing the maximum positive and negative applied factored moment. The maximum critical moment is defined as the highest ratio of the factored moment to the moment resistance (strength).
• The material resistance factors are now explicitly shown in the flexural design table for the CSA code. Also the strength reduction factor for flexural is now shown explicitly in the flexural design table for ACI 318-99.
• The number of decimal places shown for beta (gamma in AS3600) and alpha in the flexural design tables has been increased to three.
• Changed the minimum offset from the top or bottom of the beam from 25mm (1") to half of the strand or rebar diameter. This means a minimum clear cover of zero.
• The column headings of the FINAL CAMBERS/DEFLECTIONS report have been corrected. The headings of all of the deflection reports have been adjust for readability.
• The span/deflection column in thee NET CAMBERS/DEFLECTIONS AT ALL STAGES report has been changed to two reports for DL growth + LL and LL alone to match the deflection table in the Summary Report.
• Corrected a problem with the FLEXURAL DESIGN - STRAIN COMPATIBILITY DETAILS report where the results of debonded strands are not always shown where the strand is bonded. Similarly for partial length rebar.

March 14, 2005 - Concise Beam version 4.33 is now available for download

Version 4.33 includes the following changes;

• Prior versions of Concise Beam have required that a Windows subsystem called OpenGL be working properly on your computer. Any incompatibilities between Windows and OpenGL can prevent Concise Beam from starting up. These incompatibilities are caused by some older video cards or, potentially, the upgrade to Windows XP SP2. In both cases updating your video drivers will cure the problem. Starting with Concise Beam version 4.3 a properly operating OpenGL subsystem shouldn't be required except to allowing printing of the 3D beam image. This may cause interaction with the 3D image to slow down, but this shouldn't be noticeable except on some old computers (7+ years old). If you find that the 3D image moves too slowly please contact us so that we can tell you how to speed it up. This may cause previous problems to reoccur.
• Updated the license key certificates for future releases.
• Corrected the amount of additional longitudinal torsion steel required.
• Corrected the calculation of beta1 in the shear calculations for AS3600.
• Corrected the labeling of the table in the Topping dialog (h1 & h2 changed to t1 & t2).

March 5, 2005 - Concise Beam version 4.32 is now available for download

Version 4.32 includes the following changes;

• Adjusted the calculation of strand development lengths under the AS3600 code. Corrected a problem with the application of a factor to lengthen the transfer and development length for strands at the top of the beam under AS3600.
• Corrected a unit conversion problem with the reported value of the specified f'ci in the Concrete Stress table of the Summary Report.
• Removed the addition of offsets along a prestressing strand at the ends of debonding lengths.

March 2, 2005 - Concise Beam version 4.31a is now available for download

Version 4.31a includes the following changes;

• Corrected a problem with the illustration of the prestressing in the prestressing dialog for strands with debonded ends.
• Corrected a problem with the order of magnitude of the Y axis of some graphs. The problem could lead to a crash after opening the Units dialog and rechecking the graph.

March 1, 2005 - Concise Beam version 4.31 is now available for download

Version 4.31 includes the following changes;

• Corrected a problem with the loss parameters dialog whereby the program would save garbage values when using "Save the Loss Settings as Default". I have also added a button that will allow the user to reset the settings to the factory settings built into Concise Beam.
• Corrected the labeling of the concrete stresses in the custom code dialog for the ACI codes. Clarified the overstress notes in the summary report.

February 27, 2005 - Concise Beam version 4.30 is now available for download

Version 4.30 includes the following changes;

• Concise beam now supports the Australian Concrete code AS3600-2001. This support also includes a number of recommendations from NPCAA, the National Precast Concrete Association of Australia. Material libraries specific to Australia have also been added as detailed in the NPCAA Precast Concrete Handbook. These libraries use metric units though as before the user is free to work in either metric or Imperial (English) units. The support for AS3600 is added along side the existing support for CSA A23.3-94, ACI318-99 & ACI318-02. All users will have access to each of these codes. Like the other codes AS3600 can also be used as the basis for a customized design code.
• A new file format has been created for the problem files to accommodate additional data used by the program. It still uses the *.con extension but cannot be read by versions of Concise Beam prior to version 4.30. Version 4.30 will read files created by Concise Beam versions 3.x, 4.0x, 4.1x & 4.2x. Files will now be saved in the new file format.
• A new cracked section analysis facility has been implemented for the serviceability limit state. This will make cracking and deflection calculations more accurate.
• The cracking and deflection calculations have been rewritten to use the new cracked section facility.
• The graph windows now show a vertical line that will move to the right or the left with the mouse to specify a particular position along the beam (as shown on the x-axis). The ordinate (value) of each curve in the graph at this x position is given in the legend beside the description of the curve. The actual location of the mouse pointer is still shown at the bottom of the main Concise Beam window.
• Inverted the moment diagrams for the CSA and AS codes. Positive moments are now downward. Positive moments are still upwards for ACI users.
• Added a calculation option that affects the flexural strength reduction factor, Ø, under ACI 318-02. ACI 318-02 requires that the strength reduction factor be a maximum of 0.75 within the development length of a strand. This can cause a sudden drop in flexural capacity at the end of the development length. To address this problem ACI has proposed changing this reduction to a linearly varying reduction from a maximum of 0.75 at the start of the development length to the full tensile factor (usually 0.9) at the end of the development length. This change will occur in ACI 318-05. This calculation option will allow the user to use this variation in Ø under ACI 318-02 in advance of the release of ACI 318-05. Note that if a section is compression controlled Ø may be as little as 0.65.
• The user will now be asked to confirm whether or not they would like to exit most dialogs when they hit the Esc key or select Cancel.
• A new check box has been added to the Shear Reinforcing dialog labelled "Symmetrical about Center of Beam". When selected this option causes any modification or addition of a shear stirrup region at one end of the beam to be mirrored symmetrically about the centre (mid-length) of the beam.
• An option has been added to the Shear Reinforcing dialog which allows the user to specify that the beam is part of a slab system. With this option selected Concise Beam will not calculate minimum shear stirrup requirements for the beam.
• A new parameter has been added to the Loss Parameters dialog to allow the user to specify the base shrinkage strain for use with the Detailed (CPCI) Loss Method or the AS3600 Loss Method. The program had previously used an average default value for normal density and strength concrete. This value will still be the default but it can now be changed if more accurate information is available for a specific concrete.
• Previous versions of Concise Beam have based the concrete shear strength, under ACI 318, on the best of either the detailed calculation method of the simplified method, if applicable. While this gives the best possible shear strength values it also leads to an inconsistent concrete shear strength curve which doesn't agree with references. In this release we have turned off the automatic checking of the simplified method. By default only the detailed method will be calculated. If a user still wants to check the simplified method they can turn on a new option in the Calculation Options dialog of the Options menu.
• For prestressed beams, the decompression force on each section is now reported in the "Prestress Force Levels" report. The decompression report includes the decompression force in any non-stressed rebar. This report also shows the percentage of the prestress at each section which is transferred to the concrete (i.e. not lost to slippage in the transfer length).
• Increased the precision of data stored to file and used in calculations throughout the program.
• Added a new command to the view menu to allow the user to open the window showing the 3D image of the beam if it had previously been closed. If that window is closed without any other windows (i.e. a graph window) being open then the whole problem file is closed and has to be reopened.
• Cleaned up some of the section editor controls. Some of the edit modes, such as adding polygons or circles and moving or copying polygons, will now turn off after a single action. Corrected the Tab order in the Grid/Snap dialog.
• Removed the "Save Current Settings" from the Options menu. Default settings are now automatically saved or there is an options to save the defaults in specific command dialogs, such as the Libraries dialog.
• Most of the Calculation Options (Options menu) are now saved with the problem file. If you set a particular option you can now send you file to another user and ensure that they are using the same options for that problem file.
• The way standard library files are selected is now easier. The user is simply asked which standard file group to select instead of basing it on the current unit settings. Apart from being easier to use this change was required to distinguish between the Canadian and Australian libraries which are both metric.
• Corrected a number of problems that could cause crashes.
• Corrected a problem where a full length line load is not extended when a beam is extended in length. This can occur when the user makes more than one change to the beam segments each time they enter the beam dialog.
• Corrected the stress tensile stress limits under ACI for beams with lower density concrete. A density factor was mistakenly being applied (only required by CSA).
• Corrected a problem with the prestressing dialog that could prevent allowing the addition of new strands. The program complained that the added strands lay outside of the beam when leaving the dialog.
• Corrected a bug that affected the accuracy of the positive moment capacity and the depth of compression, c.

October 28, 2004 - Concise Beam version 4.24a is now available for download

Version 4.24a includes the following changes;

• This is a maintenance release while we further test and update version 4.30.
• Added the depth of concrete in tension at transfer to the stress reports at transfer.
• In the Loss Parameters dialog the air content can now be zero.
• Adjusted the calculation of bw, shear width, in the Edit Concrete Section Library dialog to avoid any chamfer or slopes on the top and bottom of the section. When searching the depth of the section for the minimum width the program will now ignore the top and bottom 50mm or 2", or 25% of the section depth whichever is less (for slabs 100mm or 4" thick or less).
• Made a correction to the anchoring of strand.
• Corrected a problem in the load analysis when the left and right intensity of a line load differs in sign.

October 15, 2004 - Concise Beam version 4.24 is now available for download

Version 4.24 includes the following changes;

• This is a maintenance release while we further test and update version 4.30.
• Updated the software protection certificates for use in future years.
• Corrected the calculation of "Prestress carried by Rebar". This is a temporary fix since it is being rewritten for version 4.30.
• Improved the detection of rebar and strand at the extreme right end of the beam.
• Changed the behaviour of the section editor so that edited sections are no longer automatically moved to lie on the X and Y axis (in the first quadrant).

September 30, 2004 - Concise Beam version 4.23f is now available for download

Version 4.23f includes the following changes;

• All previous version of Concise Beam have limited the maximum fps at ultimate to 98% of the strand strength, fpu. This is standard practice for Canadian and Australian users but apparently not for ACI users. This limit has been removed for ACI users. This will lead to a slight increase in the flexural strength, up to 2%. The next major release of Concise Beam, version 4.30, will include an option to allow users to turn this limit on or off.
• Corrected the calculation of beta for the ACI codes.

September 22, 2004 - Concise Beam version 4.23e is now available for download

Version 4.23e includes the following changes;

• Corrected a problem with the prestressing results which lead to spikes and inappropriate scales in the graphs.
• Remove an inappropriate reference to Conformance Note [1] in the shear interface table when it isn't required.
• Corrected the display of the conformance notes in the shear table.

September 12, 2004 - Concise Beam version 4.23c is now available for download

Version 4.23c includes the following changes;

• The program will now perform more checks in whether a concrete material has been defined for the topping before proceeding with the design check.
• Eliminated the inclusion of the prestress load case, P, in the list of ultimate limit state load cases in the summary report.
• Corrected a problem that allowed previously defined strands to be visible in a newly created problem file.
• Corrected a problem in the stress diagrams and section properties.
• Corrected a problem with the shear interface design where a peak negative moment at the end of the beam could be missed.
• Corrected a situation where a flexural resistance can be underestimated within the development length of a rebar or debonded strand under ACI 318-02. When this occurs the section is being found to be compression controlled when it should be tension controlled leading to a higher strength reduction factor.

August 25, 2004 - Concise Beam version 4.23b is now available for download

Version 4.23b includes the following changes;

• Corrected a problem in the prestressing dialog that could cause a crash when adding strands.
• Improved the determination of whether strand development lengths need to be extended due to tension within the development length. Previous versions checked for cracking at the end of the transfer length only. The program now checks for serviceability tension anywhere along the development length, including the transfer length, before extending.

August 14, 2004 - Concise Beam version 4.23a is now available for download

Version 4.23a includes the following changes;

• Corrected a problem in the moment calculations that could cause a sharp drop in the moment resistance at a single hold-down. This problem also occasionally affected the hold-down forces reported and the interface shear.

August 10, 2004 - Concise Beam version 4.23 is now available for download

Version 4.23 includes the following changes;

• Hold-down forces have been added to the prestressing table in the Summary Report.
• If a beam is lengthened any previously defined line loads will now be extended with the beam.
• Added a note to the shear/torsion stirrup table to note whether the required longitudinal steel is based on minimum stirrup requirements and not on a specified stirrup size and spacing.
• The wind load case can now be used for any vertical earthquake loading as well. This has always been true but now it's explicit. The standard load factors are still based on wind loading. Special load cases will have to be added for any earthquake loading.
• The governing cracking calculations are now given on the top and bottom of the beam.
• The interface shear calculations have been adjusted to ensure that the contact area of the slab/beam interface isn't wider than the beam if no haunch is specified.
• Corrected the calculation of the reinforcement ratio provided in normally reinforced concrete beams.
• Corrected a logic problem that prevented the calculation of longitudinal torsion steel if the stirrup size is specified but not the spacing.

July 30, 2004 - Concise Beam version 4.22g is now available for download

Version 4.22g includes the following changes;

• Corrected a unit conversion problem that could cause a crash while viewing analysis results before a beam is detailed.

July 28, 2004 - Concise Beam version 4.22f is now available for download

Version 4.22f includes the following changes;

• Corrected a inaccuracy in the shear calculations that could mistaking show that the level of prestressing drops below 40% in the transfer zone. This can mean that the simplified method of shear strength is not applicable. Concise Beam checks both the simplified (if applicable) and the detailed method and takes the larger result.

July 16, 2004 - Concise Beam version 4.22e is now available for download

Version 4.22e includes the following changes;

• Corrected a bug in the loss calculations which may be evident in the incorrect scaling of some of the graphs and an incorrect summary of stresses and cracking.

July 13, 2004 - Concise Beam version 4.22d is now available for download

Version 4.22d includes the following changes;

• Corrected a bug which would cause deflections at midspan to go to zero when the "Summary Report at Midspan/Tip of Cantilevers" calculation option is turned on.
• The Options menu contains a new command labelled "Diagnostic Reports". This command is still under development and should only be used if requested by Black Mint technical support. It isn't covered in the on-line documentation yet.

(NOTE: version 4.22c was not released publicly)

July 6, 2004 - Concise Beam version 4.22b is now available for download

Version 4.22b includes the following changes;

• Corrected a bug that can cause rebar at the right end of a beam from being recognized in the moment resistance calculations.

July 1, 2004 - Concise Beam version 4.22a is now available for download

Version 4.22a includes the following changes;

• A few users have found that the new moment resistance calculations based on full strain compatibility in the development length can lead to no moment resistance within approximately 600 mm (2 ft) of the ends of some slabs. This generally affects thin slabs like hollowcore with only a few strands. Adding additional strands solves the problem. The program was finding that there is insufficient development length to develop any stress in the strands beyond the decompression stress (prestress) resulting in a slip at cracking. Until this behaviour can be investigated further we have disabled strain compatibility within the development length of non-debonded strands (at the beam ends). The strength of the strands will now be linearly prorated along the development length. This will provide a moment resistance close to, if not the same as, that determined by strain compatibility. Full strain compatibility is still checked for rebar and debonded strands.

June 25, 2004 - Concise Beam version 4.22 is now available for download

Version 4.22 includes the following changes;

• The moment resistance calculations have been rewritten to allow a proper determination of the resistance at sections where some or all strands or rebar are not fully developed. Concise Beam uses strain-compatibility to determine the moment resistance. Prior to this release the program used the standard practice of linearly prorating the stress in a strand along it's development length (bilinear variation in the case of strand). This does not satisfy strain-compatibility within the section, particularly in the case of debonded strands and partial-length rebar. The program now checks whether each strand or rebar may slip (i.e., not developed sufficiently for required stress). If a slip is detected then the section is reanalysed firstly with the strand or rebar discounted (slipped), and secondly with the ultimate concrete strain reduced to prevent the slip. The program will iterate through each potentially slipped strand or rebar. The higher resulting resistance is taken as the final moment resistance. This can result in a lot of iterations in beams with a lot of strand or rebar groups. A short delay in viewing the text reports or graphs may now be noticeable when the moment resistance has to be recalculated. A new text report has been created to report the results of the moment resistance calculations in detail.
• The user-defined losses now affect each individual strand group instead of the total. The program will now report the losses at each point along the beam with user-defined losses (at transfer and final only). There is also now an option in the Calculation Options dialog that causes the program to use the user-defined loss as a minimum loss. The actual losses along the beam will vary from the minimum to account for concrete stresses. This option is ON by default. Turning the option OFF will force the program to use the user-defined losses along the full length of the beam despite the variation in concrete stresses, with the exception of the transfer lengths.
• Prestressing strand is now counted when determining the amount of steel available to resist tension in the precast beam at transfer. This is particularly important when unstressed strands are used as reinforcing in hollowcore slabs.
• Adjusted the check of the condition where the transfer and development length of strands needs to be doubled. The program had previously checked whether the precast concrete experienced any tension at service loads anywhere along the beam. It now checks whether the precast beam cracks in the development length. The transfer and development lengths re only doubled if the beam is cracked within the development length.
• The shear and torsion stirrup graph has been reintroduced with a comparison of the amount of shear and torsion stirrup steel area per unit length required versus the amount provided, if specified.
• The prestressing transfer and development length table in the Summary Report has been rearranged to show more detail. The effective and ultimate prestress used to determine the transfer and development lengths is now determined for each strand group.
• Increased the size a load that can be input to greater than 100000 to allow the use of pounds for large point loads.
• Corrected a problem with the shear stirrup dialog that prevented a user from deleting/clearing all of the shear stirrup data.
• Corrected a problem determining stresses in the calculation of Vci and Vcw under the ACI code.
• Corrected a problem with the conformance notes for the shear stirrup table.
• The long. steel required for torsion now accounts for the actual stirrup spacing if specified.
• Adjusted the minimum offset to the centre of a strand. It is now half of the diameter of the strand. The default offset for a new strand is still 25mm or 1".

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