1. COMPARATIVE STUDY OF DIAGRID STRUCTURAL SYSTEM WITH A CONVENTIONAL STEEL FRAME BY: SHAIK EHETESHAMUDDIN M.Tech (S.E), JNTUH PROJECT GUIDE: P. SRI LAKSHMI ASSISTANT PROFESSOR, JNTUH PRC-1

2.  INTRODUCTION DIAGRID STRUCTURAL SYSTEM : The Diagrids are peripheral structural configurations characterized by a narrow grid of diagonal members. It’s load carrying mechanism involves both gravity and lateral load resistance due to triangulated configuration. Diagonalized applications of structural steel members provide efficient solutions both in terms of strength and stiffness. Due to increased redundancy of the structure as compared to a conventional frame; the lateral loads get transferred swiftly along the diagrids.

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7.  OBJECTIVE : Performance evaluation of a Tall building (Irregular) with Diagrid system and its comparison with a conventional steel frame by varying the storey heights. PREMISE : * To enhance the capacity of Lateral load resistance in High-rise buildings.

8.  LITERATURE REVIEW :  Khushbu Jani, Paresh V.Patel ( ELSEVIER, 2013 ) ETABS modelling software was used for modelling & Analysis of Diagrid structures of 50, 60, 70 & 80 storeys by considering a regular floor plan. Wind load analysis and Equivalent Static analysis was performed by considering all seismic load combinations. Graphs showing Time periods, Storey shear, Inter-storey drift were plotted and explained conclusions claimed : It was observed that the lateral loads were resisted maximum by the diagrids and that the Internal columns needs to be designed only for vertical loads.

9.  Nishith B.Panchal, Vinubhai R.Patel ( IJRET, Publication yr:2014 ) Comparative study of 20-Storey RCC Frame building with a Diagrid structural system was presented. Results of both the structures were compared in terms of Top storey displacement, Storey Drift along with Steel & concrete consumption in both the cases. Conclusions claimed:  Apart from lateral loads resistance, the Storey Drift & storey shear were found much lesser in diagrids compared to simple frame structure.  The difference in the consumption of materials for both the buildings was found to be 13.01% ( i,.e for concrete ) & 57.9% ( i.e for steel ).

10.  Raghumath D.Deshpande,Sadanand M.Patil, Subramanya ( IRJET,2015 ) Comparative study of 60-Storey conventional steel Frame with a Diagrid steel structure. Wind load analysis was performed for various Modules and the Tracking Nodes were found out. Conclusions claimed:  Diagrid performs better across all the criterions such as deflections, sustainability & expressiveness.  Structural weight was reduced to about 28% less in comparison to a steel frame.

11.  Femy Mariya Thomas, Binu M.Issac ( 2 nd International conference on science,Tech & Management ) To find the Optimum Configuration for the buildings & also the Optimum angle for a Diagrid system. A fixed plan area was considered and the same area was used for modelling different configurations such as Rectangle, Square & Circular. Conclusions claimed:  Optimum angle was found to be 67.38 o which give the least Max. Storey displacement & Inter-storey drift.  Square and circular had lesser displacements and drifts compared to rectangular and the circular configuration had the least from among all.

12.  Vinay A.C, Manjunath N.Hedge ( IRJET, Publication yr:2017 ) To know the desired angle of inclination of Diagrids for structural efficiency and flexibility in architectural planning. The Model was analysed for wind loads and the Time-History analysis was performed for different diagrid angles ( 30 o,45 o,55 o,65 o ) and compared with a conventional SMRF. Conclusions claimed:  There was a reduction in Time period in case of Diagrid systems.  The increase in Stiffness of Diagrids limited the displacements and Storey drifts. ( 54% less compared to a conventional SMRF )  The optimum angle for diagrids was found to be 65 o.

13.  METHODOLOGY Analysis of both the High-rise structures ( Diagrid & Conventional ) to be carried on ETABS software. Selection of Modules ( 2,4,6-storey ) each time to create different diagrid angles and also increasing the no. of storeys if required. All the structural members to be designed as per IS 800:2007; the Dynamic wind load & Equivalent static analysis to be carried out as per IS-875 (part3)1987 and IS-1893 (part1) 2002 respectively. The frame part of both the structures to be kept as non-regular.

14. o Progress, Future plan:  Started working on Analysis of simple steel frames for different seismic methods.  Would be planning to consider a non-regular structure and considering different Seismic zones for the same structure.

15. References :  Khushbu Jani and Paresh V. Patel, “Analysis and Design of Diagrid Structural System for High Rise Steel Buildings”, Published by Elesevier Ltd.  Nishith B.Panchal, Vinubhai R.Patel, ‘‘Strategies to reduce Lateral forces on High-rise buildings’’, Published by IJRET.  Raghumath D.Deshpande,Sadanand M.Patil, Subramanya, ‘‘Analysis & comparison of Diagrid and conventional structural system’’, Published by IRJET.  Femy Mariya Thomas, Binu M.Issac, ‘‘Performance evaluation of tall buildings with steel diagrid system’’, Published by University of Delhi.  Vinay A.C, Manjunath N.Hedge, “Comparative analysis of conventional steel structure with Diagrid structures of varied angles”, Published by IRJET.