building
my home-made prototype reusable compression cylinder.
Jan 17th... I'm laid up with a bad back that has persisted for the last three weeks!
A real bore as it is preventing me from getting on with any physical work. But I'm trying to use the time constructively doing research and, particularly in these next few days, prepare for the first major presentation to the Saanich building inspectors on Wednesday Jan 20th...
Last time I wrote, about six weeks ago, I had just picked up the ingredients necessary to begin compression testing for the material to be used in the rammed earth wall. Since then there have been some interesting developments.
At the beginning of December I met with the head of the technology department at Camosun College (Interurban Campus) - Peter Burrage - and was granted access to their engineering labs in order to use their compression tester.
This was great news as it will spare me the expense of using a commercial lab thereby allowing me to experiment with different soil / aggregate / insulation mixes in order to find a combination balances adequate strength with increased insulation.
Immediately after my meeting at Camosun Clifton Schooley and I began making our first batch of test samples. Unfortunately, my relationship with Clifton came to a disappointing end when the first set of samples, made under his instruction and supervision, turned out to be an expensive and virtually useless wate of time.
The first batch of samples failed because Clifton assumed that the rammed earth would set in the plastic cylinders. This system works for cement which is 'hydraulic' and sets in the presence of water. But lime needs to absorb CO2 from the air in order to set.
Consequently, when the samples were removed from their molds after 14 days, they were still as wet as when they had been made and, not surprisingly, failed to develop any compressive strength.
Those first samples made me realise that I had to come up with a different and more effective method for creating samples. (see the photo above)
So, in mid December, I set about researching and designing my own system which will allow me to make samples and allow them to set for about 5 days inside the molds. They will then be removed and allowed to dry normally for 14, 28 or 56 days as required before doing a crush test. This system much more closely replicates the actual process of making rammed earth walls.
I have received tacit agreement from my inspections department to try out this method.
Since then Christmas has come and gone with its usual disruptions and, on Christmas eve, I put my back out so further development of the new cylinders and making of samples ground to a halt!
But progress has been made on the building designs and we are now poised to take the project into the next phase. Having redesigned and recalculated the supporting structure numerous times, we are now ready to present them to the building inspectors on Jan 20th.
This is a very exciting (and somewhat intimidating) prospect for me!
The purpose of this meeting is to present the overall design, introducing all the materials and techniques that we propose to use. Following this we will discuss in more detail the main structural elements of the foundation and supporting timber frame.
Hopefully, we can answer all the questions and address all the concerns raised by the inspectors with a view to taking the project a step closer to applying for a building permit!
A real bore as it is preventing me from getting on with any physical work. But I'm trying to use the time constructively doing research and, particularly in these next few days, prepare for the first major presentation to the Saanich building inspectors on Wednesday Jan 20th...
Last time I wrote, about six weeks ago, I had just picked up the ingredients necessary to begin compression testing for the material to be used in the rammed earth wall. Since then there have been some interesting developments.
At the beginning of December I met with the head of the technology department at Camosun College (Interurban Campus) - Peter Burrage - and was granted access to their engineering labs in order to use their compression tester.
This was great news as it will spare me the expense of using a commercial lab thereby allowing me to experiment with different soil / aggregate / insulation mixes in order to find a combination balances adequate strength with increased insulation.
Immediately after my meeting at Camosun Clifton Schooley and I began making our first batch of test samples. Unfortunately, my relationship with Clifton came to a disappointing end when the first set of samples, made under his instruction and supervision, turned out to be an expensive and virtually useless wate of time.
The first batch of samples failed because Clifton assumed that the rammed earth would set in the plastic cylinders. This system works for cement which is 'hydraulic' and sets in the presence of water. But lime needs to absorb CO2 from the air in order to set.
Consequently, when the samples were removed from their molds after 14 days, they were still as wet as when they had been made and, not surprisingly, failed to develop any compressive strength.
Those first samples made me realise that I had to come up with a different and more effective method for creating samples. (see the photo above)
So, in mid December, I set about researching and designing my own system which will allow me to make samples and allow them to set for about 5 days inside the molds. They will then be removed and allowed to dry normally for 14, 28 or 56 days as required before doing a crush test. This system much more closely replicates the actual process of making rammed earth walls.
I have received tacit agreement from my inspections department to try out this method.
Since then Christmas has come and gone with its usual disruptions and, on Christmas eve, I put my back out so further development of the new cylinders and making of samples ground to a halt!
But progress has been made on the building designs and we are now poised to take the project into the next phase. Having redesigned and recalculated the supporting structure numerous times, we are now ready to present them to the building inspectors on Jan 20th.
This is a very exciting (and somewhat intimidating) prospect for me!
The purpose of this meeting is to present the overall design, introducing all the materials and techniques that we propose to use. Following this we will discuss in more detail the main structural elements of the foundation and supporting timber frame.
Hopefully, we can answer all the questions and address all the concerns raised by the inspectors with a view to taking the project a step closer to applying for a building permit!