A dynamic leaching method for the assessment of tracemetals release from hydraulic binders using continuous concentration ofleachates.

With respect to sustainable development, the leachability of trace metal from solid materials in contact with water has focused much attention over the years. Portland cements produced in industrial kilns generally contain from 10 to 300 mg/kg of trace metals. The behaviour of these endogenous metals has been, in this regard, the target of different leaching studies. Many of these researches concluded that heavy metals release are lower than analytical detection limits. Although satisfying from an environmental point of view, it induces a lack in the knowledge about the trace metals behavior during the leaching of cement based material. Accordingly, we designed the CTG-LEACHCRETE device, a dynamic leaching system (modified Soxhlet type) that overcomes this difficulty and allows long term monitoring. The experimental procedure is presented and preliminary results are discussed

Codes and standards on earth construction

Earthen structures provide solutions to build green and sustainable buildings. Any engineered construction needs guidelines on the production of materials, construction of the structural elements, quality control methods and design guidance. There is lack of universally accepted standards on the production of earth construction materials and construction methods as compared to the standards available on conventional materials. The paper attempts to review the existing standards and norms on the earth construction, and bring out the need for comprehensive standard codes on earth construction. An analysis of the existing standard codes on earth construction has been provided. There are about 70 standards, but there is lack of coherence among the standards and globally acceptable terminology. The paper highlights the points needing attention while developing comprehensive globally applicable standards on different types of construction methods.(undefined