Feeds:
Posts
Comments

Posts Tagged ‘cast stone’

Fabric formed concrete

Fabric formed concrete


Fabric formwork provides the potential to produce forms that are both structurally efficient and architecturally compelling in a relatively inexpensive and practical manner. By careful shaping of the fabric it is possible to produce complex shapes that would otherwise be too costly to create using traditional formwork.

Chandler describes the work as “a research program that seeks to establish techniques that address complex issues of technical production, risk management and advanced passive energy control, but also accept the legitimate responsibility to be comprehensible and relevant to everyday construction and everyday use. The use of fluid responsive formwork is a technique of constructing which allows the behavior of material to engage with and influence the building process itself.”

During the research, some outcomes were surprising as different fabrics used produce varying textures and finishes on the concrete, some rough, some smooth and everything in-between. Others leave patterns on the concrete that can be reproduced time and time again. The versatility of this formwork is staggering.

Source: International Society of Fabric Forming

Read Full Post »

HiTech Lightweight Concrete made of foamed geopolymer

HiTech Lightweight Concrete made of foamed geopolymer


A new range of building products based on a novel form of foamed geopolymer is currently being developed by the CSIRO on behalf of the Company. The geopolymer-based products will add to Hitech Lightweight Concrete’s range of technologically superior building materials.

This geopolymer range of products currently under development delivers lightweight product with significant greenhouse benefits (in contrast to cement-based concrete). The green credentials of this product will position this product range very favourably compared with the high-level greenhouse gas emissions profiles of many current building materials.

Source: Loxley Intertrade.com

Read Full Post »

Foamed cement by Allied Foam Tech

Foamed cement by Allied Foam Tech


“Foamed concrete or lightweight concrete derived from Allied’s aqueous foams are suitable for both precast and cast-in-place applications. Some of the highly insulative cementitious foams at densities 48 kg/m3(3 pcf) to 645 kg/m3(40 pcf) or higher can be used as block fills, lightweight roof deck and void-fill materials. Good strength characteristics with reduced weight make lightweight concrete based on Allied’s aqueous foams suitable for structural and semi-structural applications such as lightweight partitions, wall and floor panels, and lightweight blocks. Cementitious foams derived from Allied’s premium systems are suitable for thin layer coating applications where specific performance criteria are required.

Foamed concrete and foamed cement made with Allied’s foam have very fine pore structure, unlike that made with conventional proteinaceous and surfactant foams. The pore structure of Allied’s foams hardly show any sign of deterioration as the density of the foamed cement decreases to below 160 kg/m3 (10 pcf). At densities below 160 kg/m3, the pore texture of foamed cement derived from conventional foam agents becomes so coarse that most of them show severe structural collapse….”

Source: Allied Foam Tech

Read Full Post »

No spaces between stones indicates they may have been cast in place with geopolymer.

No spaces between stones indicates they may have been cast in place with geopolymer.


There’s been a lot of interesting discussion on a previous blog post No Spaces Between Stones about building a model to show how ancient structures were made with geopolymer. To my knowledge this would be the first experiment of its kind. LeRoy Martinez, one of our readers, wants to build a small stone to test this theory. LeRoy has a background in mold making and believes he can pull this off using primarily local materials. Some of his comments are pasted below.

“I wish I had known of Davidovitz’s theory before I visited Machu Picchu. I would have certainly spent more time checking the stone texture and fit. I have a mold making background so I can see how some of these could have been cast in place.

Picture this: First they made a 4 sided box from wood and made it large enough so a person can get inside of it. There is no top or bottom. Then he covers the inside of the box with clay and he can be as artistic as he wants. He is making the reverse side of the rock. He only has to make the 4 sides of the stone. The bottom can be flat and the top is open. Then he will press decomposed granite or whatever stone they want to reproduce into the clay. When he has finished he climbs out of the box (mold) and laborers can make multiple pours of the decomposed granite and sodium carbonate solution being sure to coat all of the clay substrate that has the granite surface embedded in it. When it has cured the box (mold) is removed and the stone is finished and in place. All that remains to be done is to wash and brush off the clay.

The decomposed granite that was pressed into the soft wet clay has become the outside surface of the stone. It will provide the texture because it is decomposed granite reconstituted.

The mold can then be set on top of that stone and the procedure done all over again. No two stones will be the same because the sculptor is good at his trade and has his reputation at stake.”

You can read the entire discussion (still ongoing) here.

Read Full Post »

No one is sure why granite stones in Carnac, France weighing 100-350 tons were cut and placed in such unusual arrangement.

Read Full Post »

Tihuanaco is estimated to be over 17,000 years old, perhaps the oldest city in the world. Nearby Puma Punku is a field of ancient stone ruins that defy explanation. The stones have been carved with machine-like precision into interlocking shapes. The stones are granite and diorite. Diorite is the second hardest stone, which means only diamond tipped tools could cut the stone. Some stones weigh over 800 tons. How were they carved and moved into position from 10 miles away?

Read Full Post »

Here’s another example of ancient stonework that defies explanation. Ancient man cutting granite with the precision of today’s CNC machines (.002”). Was this done with simple hand tools? However it was done — whether carved stone or cast geopolymer — would be nearly impossible.

Read Full Post »

Older Posts »

Follow

Get every new post delivered to your Inbox.

Join 56 other followers