Inspiration for Hack
One of our team members, Jason, was a concrete formwork designer for 4 years at a concrete contracting company. Jason spent most days analyzing structural concrete slabs, beams, columns within vertical high-rise buildings to determine the best procedure to install the temporary formwork to pour the concrete in a safe and cost-effective manner.
These structural calculations would take weeks to perform for high-rise buildings, and the data was difficult to communicate in a method in which it could be communicated to others.
It is critical to determine the early-age load strength of the floor slabs to avoid the possibility of partial or total failure of the structural system due to construction overload. Decision regarding the removal of forms and relocation of the shores are too often made without the benefit of a proper analysis of the structural effects, or in many cases, without any analysis at all.
Load Distribution Methodology Used
Apatos Reshoring automates the 'Simple Method' of concrete analysis by Grundy and Kabaila (1963), which includes the following assumptions:
- The deformations of concrete slabs are considered as elastic (shrinkage and creep of concrete are neglected)
- The shores are infinitely stiff relative to the supported slabs
- The reactions of the shores are assumed as uniformly distributed
- The lowest level of shores and reshores are supported on a rigid foundation at the beginning of the construction
- The loads applied to the slab/form system are distributed between the supporting slabs in proportion to their relative flexural stiffnesses.
Construction Load Safety Factors Recognized
- ACI 318 specifies load factors for specific combinations of design loads used in design of the permanent structure. It does not however, specify load factors for construction load factors.
- ACI 347 does not specify construction load factors.
- ANSI 10.9 recommends a combined load factor of 1.3 for both dead and live construction loads.
- SEI/ASCE 37 specifies a minimum load factor of 1.4 dead load when combined with only construction and matrerial loads, and 1.2 for all other combinations, and a load factor of 1.6 for construction live loads.
What our tech does
Our first ribbon command is "Create Visualization View" which generates new 3D-geometry within the existing model by effectively tracing out of all structural elements (slabs, beams, columns) and calculating the respective construction live load for each section. The command then generates a visualization based on our calculated distribution of loads carried by the concrete structure based on the estimated strength of the concrete members to resist the construction loads imposed.
Our second ribbon command 'Place Temporary Shoring' analyzes the imposed loads, and determines an appropriate layout of reshores based on the specific conditions per point. Schedules are generated
Our third ribbon command "Create Reshoring Layout Sheets" which analyze the building data by level as well as all levels above, and generate a layout of reshores using dynamic families to place and extend the reshores to the site specific conditions.
Lastly, the fourth ribbon command "Create Pour Sheets", generates layout plans for each pour (based on pre-defined) Revit scope boxes by floor. These are field deliverables for the actual deployment of the reshores.
How we built it
Due to the complexity of vertical high-rise structural concrete and temporary formwork, a LOT of requirements discussion with our team revealed a very challenging workflow that could be automated by using BIM data effectively. While working with the team to better understand the design requirements, we spent extra time putting together some deliverables for the field. We wanted to ensure we spoke to one of the most immediate issues we identified, ensuring the field gets the information, not just the office.
We used SimpleMind to map out our ideas and understanding of the existing workflows, our research into the engineering codes, risks, standards and guides commercially available. We leveraged Trello to aggregate our initial thoughts and resources, and then later moved to a Sharepoint to
When the complexity of the design problem was better understood, we were able leverage the Revit API and C# programming to generate some pleasing visuals in testing that seemed valuable for conversations about where demand is most heavily applied.
- Automated Structural Analysis and Temporary Reshoring placement based on Simple Method
- Generation of color-coded visualization sheets, indicating demands and capacity
- Automates Reshoring Layout Sheets (by level), with Dimensions and Schedules for Loads and Reshoring Bill of Materials
- Automates Pour Sheets (by pour sequence), with Dimensions and Schedules for Loads and Reshoring Bill of Materials
- Clear visuals, indicating where additional load is applied as load is distributed down the building
- Time Savings - Weeks of effort, automated into minutes
- Less manual data entry, less potential room for human error
- Model-based takeoffs and deliverable documents for field installation
Challenges we ran into
We attempted to use PowerApps to build a data architecture to interface with to collect building structural data, but ran into issues building the appropriate connections.
Accomplishments that we're proud of
- We solved the problem we aimed to tackle!
- We also built new Revit families of reshoring poles, that dynamically adjust to the models respective site conditions for the Clear Shore Height (CSH) that did not previously exist.