More Water Under The Bridge

The relaxing sound of water accompanies this short slideshow of photos of Kay's Bridge taken by John MacLeod around March 11th 2011 after a couple days of rain. The water flows freely under this dry stone bridge which we built last October at the DSWAC Rocktoberfest event held in Landon Bay Park near Gananoque Ontario.

We first visited this Canada Parks Biosphere property over a year ago to see about building a dry stone bridge there for our four-day international dry stone walling festival and coincidently that day the creek level was at the highest John had ever seen it.

John showed us the place where he thought a bridge would look good and I took a few pictures.

The sound and sight of the rushing water was quite spectacular.

Later that week I took some time and did this preliminary rendering of what a bridge might look like there, to use in promotional material to advertise the special October bridge building event. I just went back in my files and found this picture and am pleased to see that it's not that far off what it actually ended up looking like. The volume of water in both pictures is about the same.

Maybe the rails on the drawing are not the same and the arch is not as flat as the one we ended up building but everything else is pretty much water under the bridge.

Lending A Hand

We had a challenging time figuring out how to build the dry stone greenhouse design I came up with a few years ago for a good client out west. The design called for two, four foot thick, tapered gabled walls, spaced proportionately to create the feeling of an old stone potting shed. A beam would be added later for sheets of clear glazing to be fixed to as a permanent covering and so still provide light inside. I really liked the angle design and was excited about being able to do it this year.

Several wallers, when I showed them my sketchup design (see above) at the Symposium in Ventura, said it wouldn't work and that it would spread apart or cave inwards. I invited walling expert Sean Adcock to join us on this project and together we took a lot of time thinking out how we were going to do it. At least a day and a half was spent measuring and setting up our guide posts and lines. We knew the quoins and voussoirs needed to be beefy, and that there could be no variance of the batter, or the 45 degree angle of the stone coursing, and that all the rows had to be 90 degrees to the pitch of the wall, if it was to look as good as I envisioned it.

Sean had to leave before the project was completed but I wanted to include here some of his thoughts he wrote in an email concerning the various tensions and pressures exerted on this unusual structure from the pics I sent him of the continuing building progress. Those of you who have met Sean will know he has a complex mind and analyzes things quite thoroughly in his own inimitable way.

The master with his tools- levels, squares, lines and batter frames.

"First, further thoughts re pressure on jambs. Several of my copes just sat there until I built UP to them. held in place by friction. Friction means that not all the weight/mass of stone on the incline is necessarily acting on the diagonal. Basically if its not sliding, there wont be a diagonal force. It's in equilibrium, even if it slides a little its still not 100% down the diagonal. However it still has mass which is going somewhere. Gravity suggests this is down. Basically there must be a vertical component its just a question of if/when this is transferred into a shear force by a FIXED diagonal. Do we have fixed diagonals, maybe.

If the force is vertical rather than sheer it might just mean it adds to the force becoming sheer on the next diagonal and ends up in the jamb lower in a more concentrated form, but it might just as well end up downwards. Even if it is more concentrated this should not be a concern provided the mass of the arch above the new point of action is greater than the mass acting on it from the side. If the point has moved down then there is more weight from above so it should sort of cancel.

Some of this might have implications on the bottom. The forces on the end /base boulders seem very complex. However if we assume 20" around the arch is pretty much a stable fixed mass, (we're banking on it) then looking at pics there is really very little stone in the diagonals to worry about (as it develops I am increasingly confident there is little to worry about in this respect). But as you see it develop I look at the stone and think that it's more likely that a mass could come to act just on those bottom stones.

If you tilt all the stonework in an image manipulator to form a column, then all the coping and a band of stone are acting on the bottom sandstone boulder. That is not what is happening because of the incline. However, I cannot get my head around what is happening. Some of the force from the stone cannot be acting diagonally. It must have a vertical component; how much and how this is transferred is beyond me. My gut feeling at the moment is that the end stones have greater potential to move than the arch (which would actually mean there is less pressure on the arch). I need to think more, but I've run out of whisky....

I think it is a good idea to have the heavy beam linking the apexes of the pyramids. Whatever might or might not happen roof wise. This will knit the structures visually and will also increase the load on the arch theoretically making the arch more stable. Of course I'm not that worried about the strength of the arches anyway... "

I would like to thank Sean for all his help, and of course Peter, Evan Oxland, Akira Inman and Dave Claman, who all lent a hand to complete this first stage of the potting house structure.

iMovie eClips

Inspired by the exciting news that tomorrow's winter solstice will coincide with the full eclipse of the moon, (something that apparently hasn't happened in nearly 500 years) I thought I would commemorate the event by trying my 'hand' at visualizing what a synchronization of the words 'Solstice' and 'Eclipse' might look like. After all, it seemed like they had enough of the same letters in them to attempt 'merging' the two words in a short animation.

These e-clips were created on Sketchup 7 and edited in iMovie.

As this seems a bit of a departure from 'thinking with my hands' and 'building with stones', I decided it would be appropriate to try to have the letters in both words be represented as monumental three-dimensional dry stone structures. The second half of the clip morphs back into the simpler black and white megaliths.

What do you think - crazy?

Twisted Sisters.

The twisted Sketchup preliminary drawing

The real twisted thing, completed yesterday.

Twisted brothers and twisted sisters.

Pillars of the Perverse

Speaking of twisted things, here is a photo I just came across recently of our dry stone helix being built in Garden Hill, Ontario, an unusual structure which I designed and was fortunate enough to have skilled members of the DSWAC ( Reid Snow, Evan Oxland, Patrick Callon and Stephen Nevin ) come and try to build it at the 2008 Northumberland Dry Stone Wall Festival. Like the two pillars we are building today, this was very tricky to figure out, especially how much to 'twist' the two walls as they curved upwards. The ten flat long stone rungs held the ascending walls in place and stopped the 'rubble helix' from falling over.

Our two twisted pillars were coming along well, but every stone has to be placed and shaped and repositioned several times before feeling good about it actually looking 'right'. (As if a twisted pillar can ever actually look right?) But seriously, this has turned out to be more awkward than we first realized. Recently we have been doing a lot of weird pillars. Entrance gate columns with curving Japanese style contours at one job, another one that had water flowing out from the top of it, two others that were over 6 feet tall and 4 feet thick. I'm thinking of calling this chapter in my life Pillars of the Peverse.

As promised, here are two visualizations I drew yesterday in Sketchup of this new 'twisted' project, to try to figure out how it would look - and, based on what we saw, how we would go about building it.

Below is a picture of how far we have come today on one of the pillars.

It looks like who ever was building this pillar was drunk! We have ended up using rebar as batter guides, twisting them clockwise and held in place at the top with a square piece of plywood rotated 45 degrees to the base and held with duct tape (you cant see that in this picture) Bungee cord string-lines help us to line up our stones with the 'splayed' geometry of the twisted sides.

Happy Marriage of 'Rendering' and 'Realization'.

On the theme of Sketchup once again, I include the picture of the design (in Sketchup done in February of 2008) and a photo of the finished Church Ruins which we completed the first phase of that same year at the end of May 2008. We were pleased to see how close the dry stone folly looked to the drawing.

The idea for the church with gothic windows and door was presented to me by Rick and Dale Doner. It was to be the backdrop for their son's wedding. The Doners sent me lots of pictures of walls and churches in Ireland that they had visited and liked and Rick did a rough drawing of what he envisioned.

I was new to Sketchup and played around trying to visualize it in three D and then 'locate' it (actually 'stick' it on a satellite image of the property) on Google maps. It was very gratifying not only to get the church ruins drawing as exact and pleasing looking using the Sketchup program, but also to get the structure built to match that drawing so accurately. I had to climb up a high extension ladder (in real life) on the day we finished the first phase of the ruins, in order to get the same birds-eye shot for the comparison photo, an angle which is far less difficult to achieve with a mouse, using the 'orbit tool' in Sketchup.

Thanks to the vision of the Doners and the tremendous work Joe and Evan put into it, with some great help from other wallers like Dean,Reid,Mike and Phil, the 'church ruins' dry stone project ended up looking really stunning.

The wedding, which was held later that summer apparently was a great success too. Rick and Dale sent me several pictures of the event, and while this one shot seems a little over the top, it does give an indication of how the new/old dry stone ruins fit in and how monumental a part it played in the whole marriage ceremony.