## 1 Introduction  
Egyptian governorates plan to construct linings in all canals connected to the Nile River. Canal linings are generally constructed from earth materials, such as different rock types, and the selection of suitable natural rock materials is therefore very important. Rock types are classified into three categories--igneous, metamorphic, and sedimentary--which differ in their physical and mechanical properties. Because rocks have such different characteristics, selection of the best method for evaluating them is paramount. The evaluation must focus on not only the mechanical and physical specifications, but also economic factors. Watercourse linings play a role in the sustainability of irrigation projects because they maintain the outflow features and maximize water conservation by reducing leakage. Thus, water can be used to expand and improve irrigation. Water canal linings in areas supplied by tube wells are particularly significant, because water supplied by pumps is comparatively expensive. Reduced water infiltration limits the rise in the subsoil water table, thereby increasing the vulnerability of the surrounding areas to water logging. Furthermore, due to the higher speed of the water in a lined canal, the width of the canal cross section can be reduced, which corresponds to reduced digging and stone work expenses. Liniings help in retaining the canal shape and result in improved control and a larger working head for power generation. Different materials contribute to constructing such linings, including cement, boulders, concrete, plastics, different types of stones and bricks, and compacted earth. The primary target of watercourse linings is the reduction of water loss caused by seepage. According to the strategic plan of the Egyptian Government, linings will be constructed in approximately 831 km of canals. A canal lining is an impermeable membrane that is added to the canal bed and sides to increase its life span and discharge capacity. Sixty to eighty percent of the water lost to seepage in an unlined canal can be saved by lining the canal. Watercourse linings are categorized into two major types according to the nature of their surface: earthen linings and hard-surface linings. Earthen linings are further divided into two categories: compacted earth linings and soil-cement linings. When appropriate earthen material is available close to the construction site or in situ, compacted earthen linings are the most suitable. However, if the appropriate earthen material is not available near the site, a compacted earthen lining is more expensive. Compactness undermines the soil pore volume by displacing air and water. The reduction of voids increases the density, compressive strength, and shear strength of the soil and reduces its permeability. Due to corresponding reductions in the volume and settlement of the surface, compactness is necessary to boost the stability and frost resistance, if needed. Moreover, erosion and seepage losses decrease. Soil-cement linings are made from mixtures of sandy soil, water, and cement, and are hardened to a concrete-like material. In general, for the construction of soil-cement linings, dry-mix and plastic mix methods are used. There are several lining methods that use cement concrete, such as a lining cast in situ, shotcrete lining, precast concrete lining, and cement mortar lining. In the case of a brick lining, bricks are laid using cement mortar on the sides and the canal bed. Thereafter, a smooth surface finish is added using cement mortar. The physico-mechanical properties of rock samples have a significant influence on their behavior in the application of canal linings. This study focused on the evaluation of different rock samples to determine an index and to classify the most suitable rock type with respect to a combination of their properties. Accordingly, ten samples of each type of rock were examined.