Paper Title
Review of the use of Nanotechnology in Construction Industry

Abstract
In Civil Engineering, vast improvement has been achieved through the production of materials with new purposes or by refining the performance of existing ones, today Nanotechnology is widely considered as one of the21st century’s important technologies, and its economic importance is gradually on the rise. In architecture and the construction industry it has possibilities that are already usable today, Such possibility can already be seen today through many current applications related for instance to surface coatings, self-cleaning capacity, and fire resistance, and others[1]. Nanotechnology is an extremely wide-ranging term. Most commonly, nanotechnology is defined as the understanding, control, and restructuring of matter on the order of nanometers i.e., less than 100 nm (the definition of which varies from field to field.) to create materials with basically new properties and functions [2].There are two main types of approaches to nanotechnology: The top-down approach and the ―bottom-up approach. The ―top-down‖ approach involves taking larger structures that are either reduced down in size until they reach the Nano-scale, or are deconstructed into their composite parts. On the other hand, the ―bottom-upapproach is where materials are constructed from the atomic or molecular components. So we can define Nano technology as: The science of engineering that deals with particles which are less than 100 nm in size. It is the study of manipulating matter on molecular and atomic scale. In recent years, nanotechnology showed its prospective in the field of biomedical [3,4].Electronics, robotics. In civil engineering and construction, the nanotechnology is applied in (i)concrete for reducing segregation in self-compacted concrete[5]., (ii) the use of copper Nanoparticles in low carbon HPS is remarkable[6]., (iii) the use of Nano sensors in construction phase to know the early age properties of concrete is very useful, [7]and (iv) its use in water purification system by replacing the use of granulated particles of carbon in filtration with purifiers like Nano Ceram-Pac (NCP) [8]. The present paper reviews the use of nanotechnology in many different construction fields. Keywords - Nanotechnology, carbon nanotubes (CNT’s), Self Compacting Concrete (SCC),Strengthened Concrete