International Journal of Engineering Science Invention (IJESI) ISSN (Online): 2319 – 6734, ISSN (Print): 2319 – 6726 www.ijesi.org ||Volume 8 Issue 07 Series. I || July 2019 || PP 77-81 www.ijesi.org 77 | Page To calculate the most appropriate area of Thrust block on Tee junction with opposite face having same and different diameter Rohit Mishra 1 , Dr Sunil Kumar 2 1 Department of Civil Engineering, HBTU Kanpur, India 2 Professor in Department of Civil Engineering, HBTU Kanpur, India Corresponding Author: Rohit Mishra Abstract : Thrust block are the concrete block with nominal reinforcement which are provided to prevent the failure of underground laid pipelines due to force generated by moving water or due to surge condition. According to Water Agencies Standards (WAS) (2012) who have reported that Thrust blocks are basically installed on unrestrained pressure pipelines at all tees, wyes, reducers, horizontal bends, ascending vertical bends, and dead-ends, and shall bear directly against fittings and firm, wetted, undisturbed soil .So considering the present situation of water scarcity loss of water or treated water can cause serious problem of water scarcity. In the following abstract the optimum area of thrust block is calculated for tee junction with opposite face having same and different diameter. The method used for design is simple by calculating the resultant force and then considering the safe bearing capacity of soil the area of thrust block is calculated. The term safety of factor is taken to consider the case of surge condition .The present study is done in Kanpur Nagar which is situated in India and the following value of pressure is taken from the respective place. Keywords- Bearing capacity of soil, Kanpur Nagar, Thrust block, Tee, surge. --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 30-06-2019 Date of acceptance: 1 9-07-2019 -------------------------------------------------------------------------------------------------------------------------------------- I. Introduction In the present situation of the world water became one of the most valuable resources and the importance of this resource is increasing as the amount of clean water is decreasing day by day. Therefore the wise use of water is necessary as it may cost us in long run. The present paper is based on the design of thrust block which are installed at all tees, wyes, reducers, horizontal bends, ascending vertical bends, and dead-ends and design of such Thrust Block on Tee junction and calculate its optimum area is the main objective of this study. For example consider a situation in which a following underground laid pipeline is carrying treated water now suppose a condition of surge due to which the is a sudden increase in internal pressure which produces enough internal force to cause the movement of such pipes .Thrust block work on such places which prevent the movement of such pipeline through its weight and prevents the failure from such condition. According to Gupta S.C et al (2018) who studied the effect of centrifugal force generated in Pithoragarh district in the state of Uttarakhand, India, by moving water in pipeline which produces a horizontal thrust on the pipeline bends or at joints, according to them the resistance offered by Thrust Block contain mainly three component that is 1. Frictional resistance. 2. Passive earth pressure (Lateral resistance of soil). 3. Active earth pressure (Lateral earth pressure). While Anwar et al. (2016) used genetic algorithm for the design of thrust block for water and waste water industry in Nigeria based on traditional approach by Ductile Iron Pipe Research Association (DIPRA). Traditional method is achieved by choosing the block height such that the calculated block width varies between one and two times the height. Jeyapalan et al. (2015) studied the difference in design of thrust blocks for water pipelines and sewer force mains which vary from one pipe material or standard to another just like the design of pipe wall thickness. II. Materials and Methodology Thrust Block are simply concrete blocks made up of mixture of cement , sand and aggregate .The minimum grade of concrete used for design of Thrust block is M20 which consist of 1:1.5:3 ratio of cement , sand, aggregate. Talking about the steel Reinforcement HYSD bars are used and minimum amount of reinforcement used is 0.12% of total area. The method used in design of thrust block is simple by considering the bearing capacity of six types of poorly graded soil that is soft clay, silt, sandy silt, sand ,sandy clay, Hard clay and assuming the standard