International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 05 Issue: 08 | Aug 2018 www.irjet.net p-ISSN: 2395-0072 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 1015 DEVELOPING OF AN EQUIVALENT RECTANUGLAR COLUMN FOR AN L-SHAPED RC COLUMN HAVING SIMILAR ULTIMATE LOAD MOMENT CHARACTERISTICS Ms. Kavyashree 1 , Mr. Subrahmanya R.M 2 , Mr. Shanmukha Sheety 3 , Dr.B.G Naresh Kumar 4 , Ms. Ramya K 5 1 M.Tech Student, Department of Civil Engineering, Sahyadri College of Engineering & Management, India. 2 Assistant Professor, Department of Civil Engineering, Vivekananda College of Engineering & Technology, India. 3 Assistant Professor, Department of Civil Engineering, NITTAE, India. 4 Professor & Principal, Maharaja Institute of Technology, India. 5 Assistant Professor, Department of Civil Engineering, Sahyadri College of Engineering & Management, India. ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - The structural characteristics of rectangular and circular columns can be easily analysed because the axis of centre of gravity lies within the section of the columns, whereas the centroidal axis lies outside the section in case of L shaped columns. Due to this, the section characteristics of L sections vary when compared to the other type of normal sections i.e.; rectangular and circular columns. Therefore this work deals with the study and analysis of strength parameters and nature of L section with respect to the rectangular column. This is a work on L column, as there is a lack of adequate codal provisions of this type of columns. In this project the behaviour of L shaped Columns are interpreted in the form of Interaction Diagrams. In this work an attempt is made to obtain interaction curve for symmetrical L-shaped column and compare with that of equivalent rectangular column of different B/D ratio. Key Words: Xu , Pu, Mu, NA, Interaction curve. 1. INTRODUCTION Columns are important elements which support the structures. They are the compression members and their failure may cause damage to the whole building. A column located in the building corner. In recent days irregular shaped columns are providing at the building corners and at enclosure of elevator shafts. The column may be of the shapes rectangular, circular, square, L shaped, T (tee) shaped etc. The size and cross section of the column depends on structure, height of the building and the loads acting on the structural member. The main aim of providing column is to resist against axial compression(P) and bending moments(M x M y ).These load and moment develop due to external loads, such as dead load, live load, and lateral forces resulting from wind load and seismic action and by unbalanced moments at connecting beams, vertical misalignments. IS code (IS 456-2000) and design aid (SP-16) follows the strength criteria as a support for designing reinforced concrete columns wherein the failure is defined when it comes to a limiting strain and stress in concrete and the reinforcement. An interaction diagram may be plot for any column including given specifications such as grade, percentage of steel, reinforcement detailing pattern, dimension and shape of column by evaluating strain at various locations within the column considered, there by evaluating stress that return provides load and moment values, such numerous values of ultimate load and moment resisting capacity could be evaluated at different locations once the set of ultimate load and moment resistance values are obtained it could be graphically represented as an interaction diagram where load moment envelop serves as a failure curve implying that any combination of load and moment that falls within the envelop is safe and the load- moment combination that falls on the curve as the maximum load-moment resisting capacity of the section. Therefore interaction diagrams are one of the importance factor in design of columns. 2. INTERACTION DIAGRAM Interaction diagram shown in fig-1 is a graph illustrating the capacity of a structural concrete member to resist a range of combinations of moment and axial force. The interaction diagram of the columns is drawn with a view to determine if the maximum axial load and moment exceeds the strength of the column. By changing the location of the neutral axis, giving different size of compressive and tension zones, each case will lead to a different capacity calculated from the strain distribution. Each point on the curve show design strength values of P u and M u linked to a specific eccentricity of loading wherein; P u : ultimate load carrying capacity of concrete. M u : ultimate moment carrying capacity of concrete.