A new version of STAAD Foundation Advanced (Version 7.2) is just released. This will be the last version of V8i generation product before we move to our next generation CONNECT edition. Like last release (version 7.1), it was released as a minor update. However, it contains four new foundation types and enhanced interoperability. A vast majority of users who use “Mat” foundation module will surely like ISM interoperability for mat foundation.
Detailed discussions on all new features are beyond the scope of this document. But we will briefly discuss a few items which are cornerstones of this release. For a complete list of new features and enhancements, please refer to What’s New document included with the installation of the program.
Horizontal vessel foundation: supported on piles
Now STAAD Foundation Advanced offers capabilities to design horizontal vessel foundation supported by either soil or piles. To be consistent with the wizard based input, additional pages for pile arrangement page gets added to the wizard navigation tree. If the combined footing option is chosen “Pile Cap Geometry Page” gets added at the end of the navigation page.
Similarly, if isolated option is chosen, two additional pages gets added at the end of the navigation tree to define pile arrangement for Channel end and Shell end.
Program can generate rectangular pile arrangement based on column and row spacing through simplified input wizard and then parametrically creates pile cap geometry with other inputs like edge distance and pile-in-pile cap. It is important to note, for combined pile cap, pier forces are resolved at pile cap centroid and individual pile reactions are calculated for all piles supporting the cap. As a result, calculated pile reactions are further used for design force calculations. For individual / isolated pile cap, respective pier load is directly passed on to the centroid of pile cap.
Based on popular demand, STAAD Foundation Advanced v7.2 now offers specialized foundation type which is popular in South East Asian market known as Ribbed Beam Foundation. It is a combined footing with grade beam spanning from edge to edge of the foundation. The configuration can be best described as an inverted T foundation. At the moment, the program supports Indian code only as it is a popular regional practice in India. As expected, in addition to common required design parameters for a combined footing, beam design related parameters are also required as shown below. It also includes an option to apply additional surcharge load on the beam.
The design philosophy of a ribbed beam foundation is little different than of a traditional combined foundation. So, it is important to discuss the basic design steps for a better understanding. As mentioned above, the configuration is similar to an inverted T-beam. The flange part of the T is the footing slab which is resized for geotechnical design or in other words to meet bearing capacity requirements and pass stability checks which is similar to combined footing design.
However the strength design is a bit different. It is assumed that the foundation slab (or flange portion of the T) won’t be designed for major axis moment rather entire bending resistance will be provided by the grade beam. So, the beam will be designed as a rectangular beam with longitudinal reinforcement and share stirrups. The cantilever portions of the slab on both sides of the beam is designed for transverse reinforcement and minimum reinforcement is provided for longitudinal direction.
The program supports Australian code for a few years now but pile cap design was missing from the list supported foundation types for Australian code. The new version of the program now can design pile caps for Australian code. It is based on AS 3600 2001 with amendments 1 and 2. Like pile cap design for other supported codes, pile arrangement can be created from a predefined set of configurations or can be generated through parametric rectangular or circular arrangement. Pier force is applied at the center of the cap and pile reaction is calculated which is eventually used to calculate design forces. Calculation sheet displays all detailed design steps with relevant code clause numbers and equations.
Now STAAD Foundation Advanced supports ISM interoperability for mat foundation geometry. It can either create a new ISM repository or update an ISM repository with all geometric entities including mat boundary, holes, control regions, pedestals and grade beams.
In conclusion, new version of STAAD Foundation Advanced is not just about bug fixes rather it includes many new features and enhancements. All users are recommended to upgrade their STAAD Foundation Advanced software to the currect version (version 7.2).