THE POSSIBILITY OF UTILIZING THE CONCRETE BUILDINGS DEBRIS FOR A SUBBASE ROAD LAYER
Abstract
This paper investigates the use of construction and demolition waste in road subbase. After the end of the daesh war and the liberation of the city of Mosul in Nineveh Governorate, large amounts of rubble of destroyed buildings appeared. Official statistics from the analysis of satellite images and field assessments conducted by United Nations organizations indicate that the amount of rubble resulting from the war in the city of Mosul, the center of Nineveh Governorate, is estimated More than 11 million tons
In order to get rid of this debris in a scientific and thoughtful way, a study has been made to study wastes for a layer that is under the foundation of the roads (subbase) which considered as recycled materials. Experiments and examinations of mixtures of aggregates extracted from building rubble were carried out and the clay type betonies was used for stabilization. The values of the California bearing ratio (CBR) were measured in addition to the tests of pressure, indirect tension, gradation, Swelling and Atterberg limits.
The average Specification for grading class the (A) and (B) were taken from the Iraqi specifications for Roads and bridges (SORB). research to design the subbase layer for the road, clay has been used as a binder for recycled aggregate. The percentages of clay used are 5%, 6.4%, 7.3%, and 8.7% for class (A) .10%, 12.6%, 14.3%, and16.6% for class (B). The laboratory tests were performed that include (physical examinations, durability tests, and strength tests)
The results obtained from maximum dry density test suggested that the waste materials could be compacted to reach the desired density. The approaches of this research show that the CBR test’s results value obtained from recycled concrete is significantly higher than those CBR values obtained from the ordinary subbase. The atterberg tests showed that the waste concrete material is satisfying Iraqi specifications for roads and bridges (SORB). Accordingly, the rubble extracted from the destroyed concrete buildings and stabilized with betonies clay, can be used in a sub- base layer of the road with success. This leads to a beneficial disposal of the debris of destroyed buildings.
