Building Derived Materials—Sand Mixture as a Backfill Material

The growing interest in utilizing waste materials in civil engineering applications has opened up the possibility of constructing reinforced soil structures with unconventional backfills. According to World Bank reports (2012), generation of Construction and Demolition Waste (CDW) will reach 5 billion tons by 2025 globally, out of which major generators are Asia-pacific and North America regions. Improper handling and disposal of this inert waste create environmental hazards and also occupy land space. Recycling and reuse of CDW may help to attain a sustainable ecosystem. CDW comprises wood, concrete, and brick, glass, tiles, out of which concrete and brick forms a major part and is termed as Building Derived Materials (BDM). A series of triaxial tests are conducted to investigate the stress–strain relationship and strength of BDM and a mixture of sand and BDM. The laboratory test results are used to establish the parameters required for the hyperbolic modeling of these materials. Hyperbolic parameters are varying with an increase in confining pressures and with percentage addition of BDM. Plastic properties of sand–BDM are computed with this model and well matching with experimental data. The analysis indicates that the performance of sand–BDM mixture, being both lightweight and reasonably strong, compared well with that of sandy gravel, as a backfill material.