Comparison Study between the Use of Plastic and Concrete Pipes for Redesign and Reconstruction of Sanitary Sewer Network in Baghdad City (Hay Al Karadda –Sections 903-905)


Over the recent years, the emphasis on sewerage has increasinglyswitched from provision of new services to maintenance of existing service atacceptable levels. As a consequence the need is now to rehabilitate existingsystems rather than construct new ones.The common methods of rehabilitation consist lining of the sewer pipesand that was out of the question since it decreases the diameters of the alreadyunder size sewer lines.So that, hence, it was concluded that the best method for rehabilitating theexisting system was by total replacement of the undersize sewer lines. This shouldbe done using sewer pipes with better quality material, such as PVC, GRP or firstclass concrete pipes.Modern water and wastewater pipe is either organic or inorganic incomposition. Today's organic pipe is made of petroleum-derived plastic, whichcontains preservatives, antioxidants, and stabilizers to slow down the gradual lossin strength that occurs with organic materials[1].So that redesigned the existing sewer system in AL-Karadda districtwithin the city of Baghdad by computer with the use of QBasic language. Thedesign consist concrete pipes in once and plastic pipes in other to find the best.Based on the results, it was concluded that the plastic pipes neededgradient (Smin) less than concrete pipes (0.004 m/m for plastic, 0.005m/m forconcrete), the max. soil cover for plastic pipes was equal to (3.59 m) while forconcrete pipes it was equal to (4.25m).In addition the network redesigned on themin. commercial concrete pipe diameter equal to (200mm) while for plastic pipesequal to (250mm) and that will increasing the capacity of the network.