New features in Diamonds 2011 - ENdownloads.buildsoft.eu › pdf › en › New features in... · Diamonds 2011 release info © BuildSoft NV Page 2/18 Table of Contents 1. Introduction

Release info

2011

Diamonds 2011 release info © BuildSoft NV Page 2/18

Table of Contents 1. Introduction ..................................................................................................................................... 3

2. Modeling.......................................................................................................................................... 4

2.1. Import of multiple Diamonds projects into one global project .............................................. 4

2.2. RIGID LINK elements ................................................................................................................ 4

2.3. Eccentric beam elements ........................................................................................................ 6

2.4. Variable stiffness connections ................................................................................................. 8

2.5. Arbitrary cross-sections (Section Utility) ............................................................................... 10

2.6. More efficient & extensive section library ............................................................................ 11

2.7. Import of PowerFrame section & material libraries ............................................................. 12

2.8. Support of consequence classes & design reference period ................................................ 12

2.9. Support of sub-loadcases ...................................................................................................... 12

2.10. Definition of concentrated loads & moments along bar elements ................................... 14

3. Analysis .......................................................................................................................................... 15

3.1. Extra scenario for calculation of bar elements’ buckling length ........................................... 15

4. Design ............................................................................................................................................ 16

4.1. Steel ....................................................................................................................................... 16

4.1.1. Support of EN 1993-1-3 ................................................................................................. 16

4.1.2. Support of AISC-LRFD .................................................................................................... 16

4.1.3. Import of variable connections stiffness from PowerConnect ..................................... 16

4.2. Timber ................................................................................................................................... 16

4.2.1. Support of EN 1995-1-1 ................................................................................................. 16

5. User environment .......................................................................................................................... 17

5.1. German & Polish user interface ............................................................................................ 17

5.2. Definition size of characters, symbols, loads & results ......................................................... 17

5.3. More structured access to load groups & combinations ...................................................... 17

5.4. Changes to the detail results window ................................................................................... 18


1. Introduction

This document reviews the extensive number of new functions which are released as part of the new

Diamonds 2011 version. The overview does not necessarily cover all changes in detail, but rather

attempts to provide a brief description of the major product innovations so as to make all users

aware of those new functions.


2. Modeling

2.1. Import of multiple Diamonds projects into one global project

Diamonds 2011 has been extended with a new import capability. This new capability enables the

user to import, step by step, multiple Diamonds projects and to group them into 1 new global

Diamonds project. With each import operation, the user can specify an insertion point for the newly

inserted model (see screen capture below). During the import, the origin of the imported Diamonds

model will be positioned at the insertion point as specified by the user.

2.2. RIGID LINK elements

In a structural design analysis model, bar and plate elements are described by means of their neutral

axis or neutral plane, to which the user assigns a number of structural properties. To enable the

transfer of internal forces between structural elements, those elements should be interconnected. In

most cases, the transfer of internal forces will we achieved through a number of nodes shared by

adjoining structural elements. In case of highly eccentric structural elements however, it is

recommended to adapt the modeling approach. Eccentric structural elements will not necessarily

share a common set of nodes, but will be interconnected by means of rigid link elements defined

between adjacent nodes. Rigid link elements do not have any specific physical properties (like, for

example, cross-section or material properties), but rather define a mathematical relationship

between both connected nodes (whose relative position is assumed to remain unaffected at all

times).


To define rigid link elements in Diamonds 2011, proceed as follows:

• draw a line between the 2 points which need to be connected through a rigid link element

• select the line (or a number of lines) and assign rigid link properties to the selection by

means of the icon . It should be noted that the use of this icon does not call a new

dialogue window, as no further parameters are needed to complete the definition of a rigid

link element. It is therefore sufficient to just use the icon once in order to

automatically assign the rigid link property to the selected line elements.

In case the Diamonds geometry model is being visualized using volume rendering techniques, it

should be remembered that rigid link elements are being shown as cylindrical bars. This does not

imply however that rigid link elements have any physical properties – it merely is a symbolic

representation of the rigid link elements. It should also be noted that Diamonds will automatically

assign a unique TYPE to all rigid link elements, allowing for a straighforward simultaneous selection

of all rigid link elements (for instance, to exclude them from the model display by making them

invisible).

To remove rigid link elements from the Diamonds model, the user should simply delete the

corresponding line element. To replace rigid link elements by bar elements with physical properties,

it is sufficient to just select the corresponding line elements and to assign the requested section and

material properties.

As already outlined before, rigid link elements do not have any physical properties, but rather define

a mathematical relationship between both connected nodes of which the relative position remains

unaffected at all times. As a consequence, rigid link elements will transfer all internal forces (bending

moment, torsion moment, longitudinal force, shear force) from one node to the other, taking into

account the eccentricity between both nodes (or in other words: the length of the rigid link element).


The rigid link element as such will have no internal forces, as this element does not have any physical

properties.

It remains however possible to change boundary conditions at one or both ends of rigid link

elements, just like this is possible for physical bar elements (see screen capture below). In particular,

it is possible to eliminate the transfer of bending/torsion moments from one node to the other and

to limit the transfer to longitudinal and shear forces only. A typical example are multi-span joists

which are supposed to transfer only a vertical “reaction force” to the supporting structure, and for

which the transfer of bending and/or torsion moments is prohibited by the detailed design.

2.3. Eccentric beam elements

Rigid link elements as described in the previous section, can be defined between any pair of non-

coincident points. In case this type of elements is used to connect joist elements to a number of

supporting structural elements just below the joist elements, the neutral axes of the joist elements &

the supporting elements will need to be drawn with the appropriate eccentricity (equal to the

distance between the neutral axes). In case the section dimensions of the joist elements or of the

supporting elements change at a later time (and therefore also distance between the neutral axes

changes), this should be taken into account in the analysis model by repositioning neutral axes.

This procedure can however be quite time-consuming (and error-prone), but luckily its use can be

avoided through the application of eccentric beam elements. Referring again to the example

described above, the neutral axes of the joist elements and the supporting structural elements can

now be drawn with ZERO eccentricity – as a result of which the neutral axes will intersect at a

number of positions where both elements are assumed to be interconnected. In case the joist


elements are now selected by the user, the icon will enable the user to assign an eccentricity

to the selected joist elements. The reference lines of the joist elements will be unaffected by this

operation, and will now be drawn by means of a semi-dotted line. The actual (off-set) position of the

joist elements will be drawn by means of a full line, and between both lines rigid link elements will

automatically be added at the appropriate positions (which will be drawn by means of dotted lines).

In case one or multiple joist elements are selected, the reference axis (semi-dotted) as well as the

actual position (full line) and the rigid links (dotted line) will be selected.

It should be noted that also in this case it remains possible to change the boundary conditions at one

or both ends of the auto-generated rigid link elements (see screen capture below).


The eccentric beam elements as described can also be used to account for an eccentricity between

beam and plate elements - thus replacing the approach of previous Diamonds versions, based on the

Steiner hypothesis. The Steiner-based approach works quite well as long as the neutral axis of plate

and beam remains relatively close to the neutral axis of the plate by itself. In case however the beam

elements become dominant with respect to the plate element, this hypothesis is no longer fulfilled

and the Steiner-based approach will no longer deliver accurate results. The new approach based on

eccentric beam elements through rigid links will not suffer from this limitation – and the user will

actually notice an increasing contribution of longitudinal forces in both plate and beam elements as

the eccentricity increases.

Important remark:

To guarantee absolute compatibility of existing Diamonds projects with the new approach for

eccentric beam elements, both the mesh data and the analysis results of a Diamonds 2010 project(or

a project saved with any previous version) will be deleted when such a project is opened by the new

Diamonds 2011 version – also in case the Diamonds 2010 project does not contain any eccentric

beam elements.

2.4. Variable stiffness connections

Starting from Diamonds 2010, the rotational spring stiffness at bar ends can be defined by

differentiating between positive and negative bending moments along the section’s major axis. As

from Diamonds 2011 onwards, the capabilities for the definition of boundary conditions at bar ends

has been considerably increased.

For all boundary conditions, the user can freely choose between following possibilities:

• rigid connection (transfer of all internal forces),


• free connection (no transfer of internal forces),

• elastic connection (transfer of internal forces evaluated on the basis of a user-defined

stiffness value),

• connection defined by means of a user-defined stiffness curve (see screen capture below).

In case the user chooses to define boundary conditions at bar ends by means of a user-defined curve,

the user will initiate the definition of the curve by means of the icon and will specify a unique

user name for the curve. Either, the user can choose between following options for both positive

and negative values of bending moments:

• rigid connection (“fixed”)

• free connection (“free”)

• elastic connection (“value”)

or the user can define the stiffness diagram manually (see below). It should be noticed that this

approach allows to introduce plastic hinges into the analysis model by means of a stiffness diagram

which includes one or more horizontal thresholds.


2.5. Arbitrary cross-sections (Section Utility)

Diamonds 2011 allows to assign “arbitrary” sections (sections which are freely defined by the user) to

bar elements. To do so, the user should select one or more bar elements and then start the section

definition by means of the icon . From the list of available section types, the free-form type

should be chosen, after which Section Utility can be launched by means of the icon .

By using Section Utility’s drawing capabilities or by import of a DXF-file, the user can define any type

of cross-section and have its properties calculated automatically (see screen capture below).


It is interesting to observe that the above method is also available from within the dialogue window

which allows to define the Diamonds section library (menu MODIFY – SECTION LIBRARY…). Thus, the

user can easily add self-defined sections to the Diamonds section library.

2.6. More efficient & extensive section library

Access to the Diamonds section library has considerably been improved by a new design of the

library as an actual database. Furthermore, the section library has been extended with cold-formed

sections from the SADEF portfolio. Section properties have been calculated and validated by SADEF.

In case use is being made of a section from the SADEF portfolio, the steel code check will

automatically switch to the relevant standard EN1993-1-3 for cold-formed sections.


2.7. Import of PowerFrame section & material libraries

The IMPORT function in the above dialogue window enables the user to import both EFS and EFM

files. EFS files contain section libraries for use with PowerFrame, where-as EFM files contain

PowerFrame material libraries. For those users who have built custom libraries for PowerFrame (or

who have completed existing libraries with custom data), it now becomes possible to add those data

to the Diamonds section & material libraries.

2.8. Support of consequence classes & design lifetime

EN1990 supports the concepts of “consequence classes” and “design lifetime”, which relate the

safety factors to be used during structural design analysis to the economical and/or social

importance of the building structure. Depending on the national annex, in some countries (like

Belgium, for example) an approach is used based on consequence classes – while in other countries

(like the Netherlands, for example) the approach is based on the design lifetime. Depending on the

national annex selected by the user, Diamonds will present the appropriate option and will

incorporate the parameters defined by the user into the procedure for the generation of design

combinations.

2.9. Support of sub-loadcases

Diamonds 2011 supports an entirely new concept of sub-loadcases. Sub-loadcases are being

activated by selecting the option “SEVERAL CASES PER GROUP” in the dialogue window below. Next,

the number of sub-loadcases can be defined in the column with header #.


This new concept can be used following 2 different scenarios:

• sub-loadcases - permanent load type

In this case, the icon is selected in the column headed “TYPE”. All sub-loadcases which are

part of the load group will be assumed to be present simultaneously. The total permanent load is

thus defined as a sum of permanent sub-loads – which may make it easier to change the entire load

in case only one of the sub-loads is actually changing.

• sub-loadcases - service load type

In this case, the icon is selected in the column headed “TYPE”. All sub-loadcases which are part

of the load group will be assumed to be mutually exclusive. A practical example is the definition of

wind loads, in which the loads corresponding to different directions or different internal pressure

coefficients will automatically be made incompatible without the need for any manual intervention

by the user.


This way of working allows to limit the total number of load groups and design combinations. In

particular, results access will only be available on the level of the entire load group and not on the

level of each individual sub-loadcase. Results will therefore automatically be presented as envelopes

including contribution from all individual sub-loadcases. In case the user also wants access to the

results of individual sub-loadcases, the user should actually avoid to use this new concept of sub-

loadcases – but rather continue to use to define the “sub-loadcases” as load groups. It should then

not be overlooked to still declare those load groups as being incompatible.

2.10. Definition of concentrated loads & moments along bar elements

The loads tool bar includes a number of new functions to allow for the definition of concentrated

loads & moments along the axis of bar elements.

With previous Diamonds versions, concentrated loads & moments could only be defined at existing

geometry points. To define such a load along the axis of a bar element, it was thus necessary to first

split the bar element in order to create the point which was needed for the definition of the load.

Those extra steps are no longer needed with the new, direct approach.


3. Analysis

3.1. Extra scenario for calculation of bar elements’ buckling length

Diamonds 2009 introduced the capability to calculate the buckling length of bar elements according

to 2 different scenarios:

• non-displaceable nodes – for use with a 2nd

order analysis or for use with a 1st

order analysis

of non-sway frames

• displaceable nodes (taking into account the stiffness of the adjacent structure) – for use with

a 1st

order analysis of sway frames

From Diamonds 2011 onwards, this has been reviewed so as to provide the user a choice between 3

different scenarios for buckling length calculation of (a selection of) bar elements:

• non-displaceable nodes – for use with a 2nd

order analysis or for use with a 1st

order analysis

of non-sway frames

• displaceable nodes (neglecting preservation of stiffnesss of the adjacent structure, assuming

all compression bars fail due to simultaneous buckling) – for use with a 1st

order analysis of

sway frames based on a conservative buckling length assessment

• semi-displaceable nodes (preserving the stiffness of the adjacent structure) – for use with a

1st

order analysis of sway frames

The buckling length calculation is performed using a fictitious unit load applied on the bar element,

both along the major and the minor axis of the section – taking into account the grouping of the bar

elements as defined by the user.


4. Design

4.1. Steel

4.1.1. Support of EN 1993-1-3

In addition to support of EN1993-1-1, Diamonds 2011 now also offers support of EN1993-1-3 for

cold-formed profiles. Depending on the type of profile (hot-rolled or cold-formed), Diamonds will

automatically select the relevant section of the EN1993 standard. In case of cold-formed profiles, the

design check will most often be based on the effective section properties of the cold-formed profile.

Those properties have been included in the Diamonds section library for profiles from the SADEF

portfolio. It should be remarked that those properties are not necessarily valid for profiles with the

same dimensions, but from another supplier.

4.1.2. Support of AISC-LRFD

4.1.3. Import of variable connections stiffness from PowerConnect

Diamonds 2010 already offered the possibility to introduce the rotational stiffness of moment

connections into the 3D model based on a PowerConnect analysis of the connection. During the

import of the stiffness characteristics into Diamonds, it was possible to select different stiffness

values for positive and negative bending moments. However, the user still needed to decide whether

to import the initial stiffness (“elastic stiffness”) or a reduced stiffness (“plastic stiffness”).

Diamonds 2011 offers much more advanced capabilities through the import of the entire

PowerConnect stiffness diagram into the 3D Diamonds model. As a consequence, the user must no

longer decide between elastic & plastic stiffness at the time of import, because Diamonds will

automatically select the appropriate stiffness value based on the value of bending moment

calculated at the connection node. As the stiffness depends on the value of the bending moment

(and will, for instance, be different from one loads combination to another), the calculation will

become an iterative one.

4.2. Timber

4.2.1. Support of EN 1995-1-1

Diamonds 2011 offers full support for design analysis of structures with timber members. The

EN1995-1-1 design checks take into account the so-called modification factor kmod. This factor takes

into consideration the humidity, characterised by a climate class, and the longevity of the loads

applied to the member. Both climate class and longevity of the load must be specified with the

definition of the load groups. For each load combination, the actual kmod factor will be derived to

calculate the reduced strength characteristics of timber (also taking into account the material factor).


5. User environment

5.1. German & Polish user interface

5.2. Definition size of characters, symbols, loads & results

With previous Diamons versions, the size of characters and symbols or the size of loads & results

could only be changed in the window configuration dialogue as initiated by the icon . Diamonds

2011 offers direct access to those settings within the actual working environment, as can be seen in

the screen capture below. The factors which can be defined by the user should be interpreted as

multiplication factors which are applied to the base settings that are still accessible through the icon

.

5.3. More structured access to load groups & combinations

To access design analysis results, Diamonds 2011 first prompts the user to select the type of load for

which results must be assessed:

• load groups

• ULS combinations

• SLS combinations

Depending on the choice made by the user, a further selection will need to be made to access a

specific load group or combination . This new procedure offers 2 major advantages:


• the name of load groups or load combinations can be reduced to a minimum (as a prefix to

indicate the type of combination is no longer needed), which significantly improves

readability,

• the potentially extensive list of load groups & combinations is very much reduced by splitting

it up per type of combination, again improving the overview by the user.

5.4. Changes to the detail results window

The Diamonds detail results window can be used to inspect in more detail the results on individual

bars, groups of collinear bars, individual plates or groups of coplanar plates. This detail window has

been extended with ZOOM & PAM functions, similar to the functions available in de 3D Diamonds

working window – in case the detail results window is being used to visualize results on plates.

Documents

New features in Diamonds 2011 - ENdownloads.buildsoft.eu › pdf › en › New features in... · Diamonds 2011 release info © BuildSoft NV Page 2/18 Table of Contents 1. Introduction