AggreBind is a unique, environmentally friendly, cross-linked, water based, styrene acrylic polymer with proprietary tracers. AggreBind is available in a wide range of colors to produce roads from insitu materials and for the manufacturing of blocks, bricks and pavers, for buildings and homes without using any cement.
“…with AggreBind, there exists the possibility to explore sustainable, cost effective ways of building that can benefit 3rd world countries while being sophisticated, flexible and relevant enough to also be used in 1st world countries.”
-Assistant Professor, Mark McKinney of IIT
……the result of a 25 year journey of development
Don Hawkridge, Inventor,
Managing & Technical Director of Constructive Innovations Ltd., UK
I moved to South Africa in 1975 and during the following five years I visited a number of rural sectors, townships and outlying areas. There was an obvious lack of rudimentary housing and passable roads . The overt need for affordable housing and usable rural roads was my personal motivation to seek viable solutions.
Following the 1976 riots in Soweto and the ensuing unrest, it was impossible for me to conduct meetings with the local population to discuss their needs and aspirations. As a personal alternative, I became the Marketing Director for a publication called Black Enterprise. In this position I had the unique opportunity to meet with the emerging public leaders and new businesses.
The need for affordable housing and usable rural roads remained urgent. In 1983 I was asked to find alternatives to cement for the construction of roads and affordable housing. The main reasons for this request were the cost and availability of cement and similar construction products, as these products are always controlled by a few businesses and/or individuals.
Our first alternative effort was in a fertilizer-based solution. It was tested and it had many problems including obnoxious odours and the curing process was activated by an accelerant that generated strong heat. During one of the installation contracts, the fertilizer-based solution set into a solid block within the spray tank. Needless to say, fertilizer-based solutions were not an acceptable alternative.
The quest for alternatives continued with a series of other formulations involving naturally occurring substances which most often required a high clay content to be effective. Even today many of the so-called competitors in the alternative road stabilising field rely on the binding properties of clay. From a pragmatic view of “alternatives”, a clay-based solution was ruled out 30 years ago, since clay is not always an in situ material.
Bitumen based solutions were also vigorously investigated and then later discarded, as bitumen does not meet today’s environmentally friendly requirements and on-site objectives. Both the environmental requirement and on-site objective have been my goal since I started this search for “alternatives”.
In the late ‘80s and early ‘90s I began researching “polymer-based”’ products and we carried out numerous contracts in South Africa and Botswana. Some of the early polymer-based products did increase the compressive strength of in situ soils but did not augment the soil’s tensile strength.
We did surface spraying of mine dumps in Johannesburg to prevent highly contaminated airborne dust from covering the adjacent township areas during the windy season.
We experimented with wood and timber framed structures for affordable housing but this structural concept was rejected by the local population. To the locals, the walls sounded hollow and they were concerned that the house would not be secure.
Testing was also carried out on GRC panels (glass reinforced cement) with an insulated infill. This approach failed because of jointing issues due to the high temperature variations between the inner and outer surfaces.
The road trials with various polymer formulations continued. While we were achieving solid results on compressive strength we still had the question of increasing the tensile strength of the stabilised soil.
Using the materials on hand to make bricks in Botswana we used desert sand and fly-ash. Borne out of necessity, this usage of sand and fly-ash actually laid the foundation for today’s efforts in remediation projects and converting waste products and hazardous waste products into newly purposed products and projects, such as bricks and roads.
My twenty years in South Africa taught me many things. You had to build and create from what is on hand, what is in situ. You do not always have the ability or luxury of importing first-world construction products into third-world environments. The need for affordable housing to safely and securely raise a family and the need for rural roads to move products to market, children to schools and people to medical care facilities should not be a luxury. These are the most basic of expectations in any modern society.
In 1997 I decided to return to the United Kingdom to progress this important research.
Working with a creative and experienced chemist within the most advanced laboratories imaginable I finally produced a product that significantly improved the load bearing capabilities of all soils and also increased the soil’s tensile strength. AggreBind, a crossing linking, water-based, environmentally friendly, styrene acrylic polymer was created.
Engineers and specifying authorities understood the potential impact of this new product. They requested some method to trace the quantity of AggreBindwithin any given area of the treated soil.
Again, after extensive research a tracer-element was created and became part of today’s AggreBind, a crossing linking styrene acrylic polymer with tracers. With this tracer engineers and specifying authorities now have the necessary tool to empirically assess “quality and quantity” of any installation.
In that continued quest for affordable housing, AggreBind has produced non-fired clay bricks that meet or exceed internationally recognized strength standards for blocks and international strength standards for Adobe handmade bricks and blocks. Reports are available.
In addition to our on-going business of roads and bricks, specific testing is underway on the use of AggreBind for the manufacture of bricks, blocks and roofing tiles from waste materials. Preliminary meetings have been held to examine AggreBind as a remediation treatment for a wide range of extremely hazardous materials.
Self-help community programs, for houses, schools, clinics, and job creation will feature prominently in our objectives for creating a better and healthier future for everyone.