Insulation systems for structures on pile supports

Construction on problem soils or in permafrost conditions involves using of pile foundations with a ventilated space under the floor structure. In this case, additional thermal insulation is required under the first-floor structure (above the ventilated space). This problem is com-pounded by construction in cold regions. The goal of research was to develop insulation systems for buildings on pile foundations for different climatic zones, including conditions of the arctic region and other regions with a predominance of ever-frozen ground. With the help of the THERM computer program, the conditions of bidimensional heat interchange in the enclosing structures of a building with pile foundation were simulated. The construction of such buildings is practiced on problem soils. The resulting models were analyzed in terms of the thermophysical characteristics of the structures. As a result, the optimal version of the insulation system was chosen, effective both in the climatic conditions of the midland and in the especially cold conditions of Yakutia and Trans-Polar region (The Subarctic). This system included insulation with mineral wool slabs along the facade walls, with extruded polystyrene (XPS) foams along the basement part and the floor structure, and with roll polyethylene (PE) foams (with the formation of a seamless insulation shell) along the ventilated space under the floor structure and above, on top of insulation boards.

Chemical Stabilization of Black Cotton Clay and Laterite Soil Using Drycon Powder for Suitability as Construction Materials

This paper used drycon powder (DP) as stabilization additive for improving the engineering properties of problem soils, specifically, black cotton clay (BCC) and laterite soil (LS), for use as a road construction material. The study was carried out in some parts of the Greater Accra Region of Ghana, through the conduction of index properties tests such as gradation, Atterberg limits, California bearing ratio (CBR), Compaction characteristics and X-ray diffraction (XRD) on the problem soils. CBR, Atterberg limits and environmental quality tests were specifically conducted on DP stabilized soils for comparative analysis. Gradation results revealed 38% fines for BCC and 14% fines for LS. X-ray diffraction analysis revealed the presence of quartz and montmorillonite in BCC, and quartz and kaolinite in LS. Generally, the results of the various tests conducted revealed that DP has the potential of improving the engineering properties of problem soils with significant strength improvement. It can also be inferred from the results that, DP is environmental friendly soil stabilizer.