STUDY AND BEHAVIOR OF INFILLED VIERENDEEL REINFORCED CONCRETE FRAME WITH OPENINGS UNDER STATIC CYCLIC LOADING WITH P.C.C INFILLING

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 7, pp Article ID: IJCIET_8_4_65 Available online at aeme.com/ijciet/issues.asp?jtype=ijciet&vtyp pe=8&itype=3 ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STUDY AND BEHAVIOR OF INFILLED VIERENDEEL REINFORCED CONCRETE FRAME WITH OPENINGS UNDER STATIC CYCLIC LOADING WITH P.C.C INFILLING Raja S Post Graduate Student, Civil Engineering Department, SRM University,Chennai,Tamil Nadu Sudha C Assistantt professor, Civil Engineering Department, SRM University, Chennai, Tamil Nadu Lakshmipathy M Professor, Civil Engineering Department, SRM University, Chennai, Tamil Nadu ABSTRACT In this study, an experimental and analytical investigation is carried on the behavior of infilled reinforced concrete vierendeel frame with openings under static cyclic loading using plain cement concrete for infilling material. The key variable considered on this study are the type of material used for the infill which is plain cement concrete. A total of five reinforced concrete vierendeel frames were cast, among these one is bare frame and another one is fully infilled with plain cement concrete. The remaining three reinforced concrete vierendeel frames have been infilled with plain cement concrete have openings at center, compression diagonal and tension diagonal respectively. The diagonal bending behavior have been examined along compression and tension diagonal. For comparing experimental work with analytical results, STAAD Pro software have been used.key Word: Vierendeel frame, Plain cement concrete, static load Cite this Article: Raja S, Sudha C and Lakshmipathy M, Study And Behavior of Infilled Vierendeel Reinforced Concrete Frame With Openings Under Static Cyclic Loading With P.C.C Infilling, International Journal of Civil Engineering and Technology, 8(4), 7, pp IET/issues.asp?JType=IJCIET&VType=8&ITy ype= editor@iaeme.com

2 Study And Behaviour of Infilled Vierendeel Reinforced Concrete Frame With Openings Under Static Cyclic Loading With P.C.C Infilling. INTRODUCTION The analysis of vierendeel frames is based on elastic theory where it states that all the materials and members have homogenousproperty. The ultimate load of vierendeel girders having certain span and cross sectional properties is independent of the height of the frame. The ratio of height to span has an impact on the strength and stiffness of the frames. Vierendeel frames of having very ow height/span ratio subjected to huge amount of tensile forces in the lower chords produce full-depth tensile cracks. This tensile cracks must receive enough attention in their design []. The function of the diagonal members should be taken over by the other members that are subjected to flexural and shearing stresses. The analysis of the vierendeel frames is done by using various methods among them panel method gives accurate solution with minimum numerical work[]. Normally, vierendeel frames are highly indeterminate structures its exact calculation need more number of numerical equations. A statically determinate vierendeel systems is formed by introducing hinges at the midpoints[3]. The strength of the infill plays important influence in global performance of the structure. The structural behaviour of the frames is based on the type of material used for infill and their values of Young s modulus. The strength and stiffness of the structure is varied with the size of the openings provided in the infill[4].vierendeel system of structures are commonly used in buildings such as hospitals, laboratories where they require more flexibility for their mechanical network of pipes and ducts. And it is also used in buildings where large openings utilised for circulation[5]. A vierendeel type of frame offers maximum benefit when it is infilled and it also have more stiffness[6]. The composite action of Reinforced concrete beams with plain masonry walls have been studied. The load carrying capacity of the brick infilled frame is to be greater against larger deformation than ordinary frames with bracing[7]. The behaviour of infilled beams under cyclic loading have been investigated and found that the behaviour of infilled beam was similar to that of solid beam at low loads before cracking. The vertical stiffness and strength of two infilled beams similiar to that of vierendeel girders subjected to cyclic and reversed cyclic loading[8]. When vierendeel structures are infilled, the first crack load and ultimate load of the frames are increased. Based on the characteristics of the infill the stiffness and failure could be varied from frame to infill. Fibre concrete infill give better load carrying capacity and stiffness than brick infilled and ferrocement infilled vierendeel systems [8]. The right material for infill and its properties should be considered in the analysis and design [9]. The fundamental period, inter-storey drift ratios, infill stresses and the structural member forces in seismic design are influenced by the size of the opening of the infill. The larger size of the infill opening indicates that the decrease in stiffness is much more effective than the decrease in mass[]. This paper presents the modelling and analysis of a two bay single storey plain cement concrete infilled frame subjected to static cyclic loading. STAAD Pro software was used to perform analysis work. The effect of plain cement concrete used as infill under loading on the vierendeel frame has been studied.. MODELLING AND ANALYSIS The modelling and analysis can be done by using STAAD PRO software package. A total of five different reinforced concrete vierendeel frames were modelled in staad pro software. For easy comparison and understanding of outputs same span of 75mm x 7 mm was adapted for all frames, among these five models one is bare frame and another one is fully infilled with plain cement concrete. The remaining three reinforced concrete vierendeel frames have been infilled with plain cement concrete have openings at center, compression diagonal and tension diagonal respectively. The horizontal members of five models having a cross section of mm x mm and the cross section of vertical members are mm x 75 mm editor@iaeme.com

3 Raja S, Sudha C and Lakshmipathy M. DETAILS OF FRAME The horizontal and vertical members of the frame have been reinforced with 4 Numbers of 8mm dia. The members are enclosed by rectangular stirrups of 6mm at a spacing of 4 mm c/c A single storey two bay frame of respective dimensions are modelled in STAAD pro software and hinged supports are provided. The property of the materials used are shown in table Table Properties of materials Name of materials Density Modulus of elasticity (kn/mm3) (N/ mm) Poisson s ratio Concrete Steel x5.3 Plaincement concrete A single storey two bay frame of dimension 75mm x 7 mm are modelled in STAAD pro software and hinged supports are provided. A load of kn was applied at the top of the central vertical member. Figure Bare frame model The displacement of the frame varied with different loads were recorded. A graph plotted against load deflection values results in a convergence graph shown in Figure. The infilled frame was modelled with the same dimensions and the material properties used to model the infill namely plain cement concrete are given in Table. The infill portion of the frame was modelled by using the option called four noded surface elements. The thickness of the infill was taken as mmm in all frames. Then frame modelled first was fully infilled and a static load of kn was applied at the at the top of the central vertical member. The displacement values of the frames varied with different loads are observed and noted. Based on these values a linear graph is drawn shown in Figure. Then infilled frame modelled next having openings at centre and aload of kn applied at the top of the central vertical member. The infilled frame having openings at the compression diagonal and having openings at tension diagonal was modelled respectively and the respectivee load vs deflection curves were drawn figure 3 and figure 4. The displacement of the frame values varied with different loads are shown and the graph drawn with load vs deflection values results in a linear graph as shown in Figure editor@iaeme.com

4 Study And Behaviour of Infilled Vierendeel Reinforced Concrete Frame With Openings Under Static Cyclic Loading With P.C.C Infilling 4.5 DEFLECTON(MM) LOAD(kN) Figure Load vs deflection for bare frame 3. RESULTS AND DISCUSSION Figure 3 Infilled frame model The above graph showed thatt the stiffness of the bare frame is 7.33 kn/mm. From that the effective stiffness of the fully infilled frames having infilled with plain cement concrete and infilled frame having openings at centre were kn/mm and 9kN/mm respectively. Then the effective stiffness of infilled frames having openings at on load diagonal and openings at off load diagonal were 8kN/mmm and 6kN/mm. Typical load deflection curve for different frames were drawn, from that the stiffness of the five different frames are given in Table editor@iaeme.com

5 Raja S, Sudha C and Lakshmipathy M Figure 4 Infilled frame model with openings at centre Figure 5 Infilled frame model with openings at tension diagonal Figure 6 Infilled frame model with openings at tension diagonal editor@iaeme.com

6 Study And Behaviour of Infilled Vierendeel Reinforced Concrete Frame With Openings Under Static Cyclic Loading With P.C.C Infilling Figure 7 Maximumm principal stress contourdiagram for fully infilled frame Figure 8 Maximum principal stress contour diagram for infilled frame with openings at centre Figure 9 Maximum principal stress contour diagram for infilled frame having openings at on load diagonal editor@iaeme.com

7 Raja S, Sudha C and Lakshmipathy M Figure Maximum principal stress contour diagram for infilled frame having openings at off load diagonal DEFLECTION(MM) LOAD(KN) Figure Load vs deflection for fully infilled frame.5. DEFLECTION(MM) LOAD(KN) Figure Load vs deflection curve frame having openings at centre editor@iaeme.com

8 Study And Behaviour of Infilled Vierendeel Reinforced Concrete Frame With Openings Under Static Cyclic Loading With P.C.C Infilling DEFLECTION(MM) LOAD(KN) 3 Figure 3 Load vs deflection for frame having openings at tension diagonal.5.54 DEFLECTION(MM) LOAD(KN) Figure 4 Load vs deflection for frame having openings at compression diagonal Table. Comparison of stiffness TYPE OF FRAME STIFFNESS(kN/ mm) Bare frame 7.33 Fully infilled 7 Openings at centre 46 Openings at on load diagonal 34.4 Openings at off load diagonal CONCLUSION From the analytical results, the fully plain cement concrete infilled vierendeel reinforced concrete frames shows better stiffness compared with other frames. The behaviour of bare frame less efficient than other frames and among the infilled frames, frames having openings at the center is more efficient than the frame having openings at tension and compression side. The infilled frame having openings at tension side is less efficient than the frame having openings at compression side. The above results show that location of openings and loads in the infill has major impact on the stiffness.from this study it shows that the vierendeel frame having openings at compression diagonal side have high stiffness than frame having openings at the tension side of the frame. Generally, infilled vierendeel frames are used in hospitals and editor@iaeme.com

9 Raja S, Sudha C and Lakshmipathy M laboratories where these type of buildings require more flexibility of space for pipes. The above investigation prefers infilled vierendeel frame having openings at the tension diagonal is having better application compared with other infilled frames. 5. REFRENCES [] T.P.Ganesan,P.C.Varghese,H.Achyutha An investigation on the strength and behaviour of reinforced concrete vierendeelgirdres PhDthesis,Department of civil engineering,indian Institute of TechnologyMadras,Chennai 969. [] The Vierendeel David J. Wickersheimer Journal of the Society of Architectural Historians, Vol. 35, No. (Mar., 976), pp [3] An investigation on the strength and stiffness of infilledvierendeel girders N.Ganesan and A.Jaiferali Indian concrete journal vol.76,no.6,july,pp [4] Investigation of Infill Panels Made from Engineered Cementitious Composites for Seismic Strengthening and Retrofit Keith Kesner and Sarah L. Billington ASCE5 [5] Structural Modelling Of Vierendeel Beams With Semi-rigid Joints,Alexandre Almeida Del Savio XXVI Iberian Latin-American Congress on Computational Methods in Engineering,, 5 Paper CIL -633, Pg -63. [6] I. A. el Demirdash, (5), Statics of the Vierendeel girder, IABSE publications, pg [7] Brick infilledvierendeel girders as foundations for low lying,low bearing capacity soil terrain S.Sundaramurthy and A.R.Santhakumar ICJ,vol.79,no.,jan5 pp [8] An experimental study on reinforced concrete partially infilled frames Ozg ur Anil Sinan Altin July 6 science direct [9] Finite Element Micro-Modeling of Infilled Frames P.G. Asteris, Electronic Journal of Structural Engineering (8) 8 [] J. Dorji and D.P. Thambiratnam, (9), Modelling and Analysis of Infilled Frame Structures Under Seismic Loads, The Open Construction and Building Technology Journal, Issue 3, pg9-6. [] Behaviour of infilled girder with openings under static cyclic loading K.R.Dhineshraja,Dr.M.Lakshmipathy vol.4 IRJET vol.3,no.4,(6) p.p editor@iaeme.com