20091125

Calculating Pour Volumes


I'm sort of a feral child, and people ask me questions to which there might already be perfectly good answers. This time, the question was "In Revit, is there a way for me to analyze large concrete pours for irregular concrete elements?" I never heard back if it was useful, so you can be the judge.
Lets say you have a large irregularly shaped concrete element, like one of these:


or these:


You need to model and schedule it not only as a single monolithic element, but also as a series of pours that will happen in stages. What to do?


First, make your irregular shape in an external family of whatever category makes sense for your use. Here I'm doing it as a generic model (you can start this way and change it to, say, structural foundation if you need).


Next, take the whole complex chunk and slice it up at regular horizontal intervals. To do this, go to an elevation view and make 2 reference lines with parameterized dimensions (label them "top" and "bottom") to the reference level. Make void geometry on the horizontal workplane of each ref line, one going up on the "top" ref line, the other going down on the "bottom" ref line. These voids should each be large enough to completely cut the base form.



Now cut the complex geometry with your voids.




You now have a basic rig to move this slice of your solid geometry up and down the form.

Make as many types as you will have pours. For this example I have only 6 ridiculously deep pours of 20 feet each: 6 types, called pour 1 to pour 6, you may require more, shallower slices. Pour 1 is going to be the slice starting at 0' and ending at 20'. So bottom dimension is set to 0' and top is 20'. Progress up through each pour at 20' intervals.




Also make yourself a type "whole", with bottom set at 0' and top set over the top of the form. This will give you one type that shows the whole form for you to continue making design changes.



Load the family into the project environment and place 6 copies of the family in the same location. Set each instance of the family as a different type so that you have an instance of each slice and so make a reconstituted whole.


In this way the entire monolithic element can be instantiated as a series of pours by a single loaded family with many types, and each pour can be scheduled independently.
The nice part about this is that you get your schedulable volumes that are still fully integrated with your original form. To make changes, simple go back to your loaded family and make alteration to the "whole" type and reload it into the project for updates.


Bonus exploration for those who are interested: REBAR! I have no idea how this would work with rebar, I don't do much in Revit Structure, but I suspect that it would work nicely.

20091108

Buy the Mug, Drink the Kool-Aide


I have succumbed to the pressure to commercialize. Now you too can own a buildz mug, complete with the best bizarro Revit journal comment.

Of course, with the holidays coming up, you will also want to stock up on buildz apparel:



20091105

Halloween Hangover


A word on pumpkins: We all seek perfection, whether it is in mathematics, words, community, whatever. In form and form making, the ancients found perfection in rational shapes: circles, squares, and triangles . . . and people, somehow. Frank Gehry likes fish, Frank Zappa likes tweezers and poodles. For me, it's pumpkins. They are earthy, but technicolored. Lumpy and irregular, but unmistakably characterized by a rhythmic segmentation. They embody the Vitruvian ideal of Firmness, Commodity, and Delight.
This is the pumpkin I did last week, with the "bulge" parameter at 16', 8', and 4':