Contents
Overview
ADC 7.2 offers the analysis and design of reinforced concrete beams (AdRib),
ribbed slabs (AdRib) and flat, one-way spanning slabs (AdSlab). The design is
carried out to satisfy BS8110 or BS8110 (Hong Kong) requirements.
Status
These release notes are issued with ADC version 7.2. This is a general issue
of ADC.
Note that DOS ADC data files cannot be read by this version of ADC.
Differences between DOS and Windows ADC
There are a number of factors which are different from the DOS version and
these may lead to differences in the details. Some of these are as follows:
- The analysis solution uses the GSA solver and details of the modelling
may be slightly different.
- For a sway frame model the wind loads are applied in a different manner
to DOS ADC. The wind load is applied either at the beam level or at the
level above as outline in BS8110.
- There is an option in the General Specification dialog to allow the
support moments to be adjusted to take account of the width of the
support. This option rounds the peaks on the bending moment diagram.
- The redistribution is carried out only on the DI/DI/DI/... load case.
- The area of steel is calculated based on the recto-parabolic stress
distribution rather than the simplified stress block.
- The minimum factor on the area of steel is applied only to the mid-span
sagging moment, as this factor is to allow for the maximum error in the
moments due to interpolation at 21 discrete points along the span.
- Fewer large bars are preferred to satisfy the area requirements instead
of more small bars.
- The number of bars that can be fitted into a beam section are calculated
on the basis of a cover + link diameter + link radius and adjusted for
the column steel. This can led to a different selection of bars compared
with the previous version. The maximum number of bars will be affected
by the maximum bar size allowed.
- The bar arrangements are selected using the following scheme:
- one layer - bars not bunched
- two layers - bars not bunched
- three layers - bars not bunched
- one layer - bars bunched
- two layers - bars bunched
- three layers - bars bunched
In slabs there is a maximum of a single layer.
- If a bunched solution is required the maximum number of bars per layer
is based on the sum of the equivalent diameter not exceeding 40% of the
beam width. The bars are assumed to be bunched in a maximum of threes
for beams and ribs and a maximum of two for slabs.
- A bunched bar solution will not produce mixed diameters.
- Curtailment calculations are based on establishing the position at which
the bars are no longer required and adding an anchorage length beyond
that. If it is not possible to provide the required anchorage so the
curtailment position is adjusted to be at the cut-off point and the area
of steel in the end zone is increased from 50% to 100% of the main
steel.
- Slabs can be designed using the Simplification of load arrangements in
BS8110 (3.5.2.3) but the user should check that this is valid for his
particular case.
- An option allows for the design to conform to the Arup "Reinforcement
Detailing Manual"
- The support conditions for ribbed and flat soffit slabs have been extended
compared with the DOS versions.
New features in Windows ADC
There are a number of new features in the Windows version of ADC. Some of
these are as follows:
- A wizard allows the initial definition of the model.
- File locking has been introduced to prevent accidental use by more
that one user.
- Output view can now be tailored without having to close the view and
open a new view.
- Self weight can be included in the calculation. This is switched on
in the "General Specification" and is applied based on the weight
density of the concrete.
- Additional checking has been added to ensure that the loads are
applied on the beam and not in space off the end of the beam.
- Rib sections are checked to ensure that the depth is less than four
times the rib width.
- File locking has been introduced to prevent accidental use by more that
one user.
There are a number of new features in ADC 7.2 compared with previous versions
of ADC 7:
- Both code prescribed and user defined loading can be defined. Either or
both can be used in the analysis and design.
- Option to open ADC file created in GSA for beam design.
- Unlock option to clear imported results.
- Includion of notional horizontal loads (BS8110 cl 3.1.4.2).
- Export of DXF files.
Design procedure
The beam design is split into three phases:
- Analysis
- Redistribution
- Design
The design phase is structured as follows:
- Identification of critical sections
- Set number of layers
- Calculate the area of steel required
- Check continuity requirements
- Check compatibility requirements
- Preliminary shear checks
- Select main bar arrangement
- Select links
- If no bar arrangement found
- if number of layers < 3 go to 2
- If number of layers = 3, reset number of layers and go to 2,
but look for bunched solution
- Check the effective depth
- Calculate the curtailment
- Check the span-depth ratios
Bugs Fixed
The following bugs in 7.1.3 have been fixed in this version.
-
Exporting GSA data from ADC results in an empty GSA model.
[7.1/03]
-
Selecting the option to allow mixed bar sizes could cause AdBeam to fail
to design the section when the best bar arrangement involved single bar
sizes only at a certain span position.
[7.1/04]
-
AdRib designs are being treated as beam design (using a beam template).
This applies beam design limitations on the rib design. The specific
case in which this was observed was in not allowing a single bar to
reinforce a rib, but other issues may be affected.
[7.1/05]
-
AdSlab designs were using a beam template (similar to the problem with
rib design above). This led to missing information in the slab design.
[7.1/06]
-
ADC will sometimes encounter problems with the vertical element tolerance
for analysis of the subframe. This results in incorrect axial loads in
columns. The correct column axial loads can be calculated from the sum of
the span shear forces.
[7.1/07]
Bugs Outstanding
The following bugs were known to exist at the time of release.
General
Restrictions
The following restrictions were known at the time of release.
General