Parametric Study of Dome Structure under Pulse Loading History of Blast Load

Transcription

1 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Paraetric Study of Doe Structure under Pulse Loading History of Blast Load Mohaed sahal M. Kazi 1, Dipali Y. Patel 2 1( Post Graduate Student (Structural Engineering), Departent of Civil Engineering, Chandubhai S. Patel Institute of Technology, Charotar University of Science and Technology, Changa, Gujarat, India) 2( Assistant Professor, Departent of Civil Engineering, Chandubhai S. Patel Institute of Technology, Charotar University of Science and Technology, Changa, Gujarat, India) Abstract :Now a days, due to increasing terrorist attacks, a need is arise to design the doe structures which can resist the blast loads. The bob explosion can cause vary serious daage on the doe structure. In this paper an attept has been ade to analyze the doe structure for different pulse history of blast load and to check the effect of sae by changing the thickness of doe. Soe critical four pulses like Half + and half triangular pulse, full cycle cosine pulse, rectangular pulse and irregular pulseare developed in C sharp. Analysis of doe is carried out to study the effect of four-critical pulse loading history with variable thickness of 1, 2, 2 and 3 with different blast explosion of.1 tonne,. tonne and 1 tonne. Thus, on the doe structure soe stresses and acceleration ay develop due to that pulses and the sae are critically assessed. Keywords:Spherical does, Pulse loading history, C sharp, es, acceleration. I. INTRODUCTION The pre-einence of Does is in their strength and stiffness that they stand without support of coluns. Curvatures rotate about central axis to for a surface characteristically used as a roof to create a doe. Most of the are created by revolution of surfaces. It creates axiu aount of space with iniu weight which leads to be very econoical in ters of constructional aterials. They are ost efficient structure specially as roof structures. The axial behavior of does and coupling aong the bending which ake the difficult to analyze. The function of does largely affected by geoetry and shape. The loads acting on does are resisted by its own weight. The does are one of the ost efficient shapes in the world. It is lightest structure to cover up the circular shape. R.C.C. does are water, fire and wind resistant. Doe structure is easy to aintain and also econoic then other buildings. The structure has any different accept that ake it the best choice in construction. The other buildings life easured in decades but the life of doe can be easured in centuries. Doe having arch shape often used for a concrete shell as they are naturally strong due to their shape. Different kinds of loads like DL, LL and WL are acting on structures during its entire life period but due to increasing nuber of terrorist attacks and the accident accurse in laboratories so it is very iportant to analysis and thedesignof doe structure to be safer against the blast load. Due to blast, air pressure generate on a structure above ground level is basically a single pulse and can frequently idealize by siple shapes. A blast is characterized as a sudden arrival of energy. These can be further set by physical, substance and atoic occasions. In physical blasts, vitality ight be discharged fro the calaitous disappointent of a barrel of a copacted gas, volcanic ejection or notwithstanding blending of two fluids at various teperatures. In an atoic blast, vitality is discharged fro the developent of various nuclear cores by the redistribution of the protons and neutrons inside the collaborating cores, while the quick oxidation of fuel coponents (carbon and hydrogen iota s) is the principle wellspring of vitality on account of cheical blasts. To coprehend the ipact of this blast on structure, we have to characterize the "Blast Wave". It is a pressure wave produced noticeable all around by quick arrival of vitality put away. This vitality can be put away as gas or vapor, either hot or frosty. The cases of blasts are disappointent of a high weight gas stockpiling vessel or boiler which offers ascend to an ipact wave in air. Nubers of researchers have acquired the developent of shock spectra for different pulse shapes using C sharp. Manav et al. (217) has worked on developent ofthe sock spectra for special ipulse excitation. Single degree of freedo (SDOF) syste used to evaluate the effect of daping on various shock spectra. To evaluate the response of syste, piece-wise differential equation ethod has been considered. The different shape of pulse like First half triangular pulse, second half triangular pulse, Full cycle sine wave pulse, Trapezoidal pulse are developed. %, %, 1%, and 2% daping ratios are considered. This shape of pulse developed to generate different shock spectra using C Sharp. For given value of ipulse load the dynaic agnification factor (DMF) is the axiu for Full sine wave pulse followed by trapezoidal pulse, first half 4 Page

2 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP triangle pulse and second half triangular pulse. Reductions see proportion for change in daping. Raise in daping reduce the dynaic agnification factor(dmf) values for all ipulse loads. Abdalla and Mohaed (28) have worked on the paraetric study of the relationship between reinforced concrete doe thickness, height, shape, and their dynaic characteristics, frequency of vibration. United Arab Eirates (UAE) is contiguous to the Iranian plateau which is one of the ost seisically active areas of the world. The large span of does with different shapes like ellipsoidal, spherical paraboloidal are considered. The behavior of large span reinforced concrete does under earthquake loading and the incorporation between these does and the rest of the structure is not studied. The first step towards the assessent of seisic vulnerability of building with large reinforced concrete does. For study concluded that the increase in the doe thickness, increases the frequency of vibration of both paraboloidal and spherical does. The increases in doe height decrease the frequency of vibration of both paraboloidal and spherical does. II. MODELING AND ANALYSIS (A) Analysis of doe with variable thickness Analysis of doe for blast paraeters due to the detonation of 1 tonne,. tonne and.1 tonne explosive, situated at 3 fro ground zero. - Doe Structure data Diaeter (D) Height (H) Radius (R) Material property Weight per unit volue (Concrete) = 2 kn/ 3 Modeling = 3D odel in SAP2 version19 (t) Material and Doe Type (R.C.C) Spherical - Following are the different blast pulse acting on the doe structure which ay be created in C sharp in for of tie vs. acceleration. 1. Half + and Half Triangular Pulse 2. Full Cycle Cosine Pulse 3. Rectangular Pulse 4. Irregular Pulse Page

3 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP (1) Half + and Half Triangular Pulse Acceleration (2) Full-Cycle Cosine pulse tie Acceleration (3) Rectangular Pulse tie Acceleration (4) Irregular Pulse tie Acceleration tie III. ANALYSIS RESULTS AND DISCUSSION 1 tonne explosive analysis result Table 1 es for Half + and Half triangular pulse for 1 tonne blast explosion () (N/ 2 ) Doe Half + and Half triangular pulse Page

4 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Half + and Half - Triangular Pluse Table 2 Acceleration for Half + and Half triangular pulse for 1 tonne blast explosion Acceleration /sec Doe Half + and Half triangular pulse Half + and Half - Triangular Pulse Table 3 es for Full cycle cosine pulse for 1 tonne blast explosion N/ Doe Full cycle cosine pulse Page

5 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Full Cycle Cosine Pulse Table 4 Acceleration for Full cycle cosine pulse for 1 tonne blast explosion Acceleration /sec Doe Full cycle cosine pulse Full Cycle Cosine Pulse Table es for Rectangular pulse for 1 tonne blast explosion N/ Doe Rectangular pulse Page

6 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Rectangular Pulse Table Acceleration for Rectangular pulse for 1 tonne blast explosion Acceleration /sec Doe Rectangular pulse Rectangular pulse Table 7 es for Irregular Pulse for 1 tonne blast explosion N/ Doe Irregular Pulse Page

7 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Irregular Pulse Table 8Acceleration for Irregular Pulse of 1 tonne blast explosion Acceleration /sec Doe Irregular Pulse Irregular Pulse tonneexplosive analysis result Table 9 es for Half + and Half triangular pulse for. tonne blast explosion N/ Doe Half + and Half triangular pulse Page

8 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Half + and Half - Triangular Pulse Table 1 Acceleration for Half + and Half triangular pulse for. tonne blast explosion Acceleration /sec Doe Half + and Half triangular pulse Half + and Half - Triangular Pulse Table 11 es for Full cycle cosine pulse for. tonne blast explosion N/ Doe Full cycle cosine pulse Page

9 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Full Cycle Cosine Pulse Table 12 Acceleration for Full cycle cosine pulse for. tonne blast explosion Acceleration /sec Doe Full cycle cosine pulse Full Cycle cosine Pulse Table 13 es for Rectangular pulse for. tonne blast explosion N/ Doe Rectangular pulse Page

10 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Rectangular Pulse Table 14 Acceleration for Rectangular pulse for. tonne blast explosion Acceleration /sec Doe Rectangular pulse Rectangular Pulse Table 1 es for Irregular Pulsefor. tonne blast explosion N/ Doe Irregular Pulse Page

11 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Irregular Pulse Table 1 Acceleration for Irregular Pulsefor. tonne blast explosion Acceleration /sec Doe Irregular Pulse Irregular Pulse tonneexplosive analysis result Table 17 es for Half + and Half triangular pulse for.1 tonne blast explosion N/ Doe Half + and Half triangular pulse Page

12 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Half + and Half - Triangular Pulse Table 18 Acceleration for Half + and Half triangular pulse for.1 tonne blast explosion Acceleration /sec Doe Half + and Half triangular pulse Half + and Half - Triangular Pulse Table 19es for Full Cycle cosine pulse for.1 tonne blast explosion N/ Doe Full Cycle cosine pulse Page

13 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Full Cycle cosine Pulse Table 2 Acceleration for Full Cycle cosine pulse for.1 tonne blast explosion Acceleration /sec Doe Full Cycle cosine pulse Full Cycle cosine Pulse Table 21 es for Rectangular pulse for.1 tonne blast explosion N/ Doe Rectangular pulse Page

14 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Rectangular Pulse Table 22 Acceleration for Rectangular pulse for.1 tonne blast explosion Acceleration /sec Doe Rectangular pulse Rectangular pulse Table 23 es for Irregular Pulsefor.1 tonne blast explosion N/ Doe Irregular Pulse Page

15 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Irregular Pulse Table 24 Acceleration for Irregular Pulsefor.1 tonne blast explosion Acceleration /sec Doe Irregular Pulse Irregular Pulse IV. CONCLUSION Paraetric study of spherical doe structure is carried out for the different thickness of 1, 2, 2 and 3 with the blast explosive weight of.1 tonne,. tonne and 1 tonne. It is concluded after the analysis that the axiu stresses are developed in the doe with lowest thickness of 1. A doe with 1 thickness is safe for.1 tonne explosion of blast but for. tonne to 1 tonne explosion of blast the stresses are varying fro 21.8 MPa to 31.2 MPa and which exceed the perissible liit of 8. MPa as per IS 4: 2. 2 and 2 thickness of doe structure are safe for.1 to. tonne explosion of blast and not safe for 1 tonne explosion of blast as the stresses are and 17.2 respectively. They are beyond the perissible liit as per IS 4:2. 3 thickness of doe structure is safe for blast explosion of.1 to. tonne and the stresses are nearest to the perissible liit for 1 tonne explosion of blast Page

16 International Journal of Latest Engineering and Manageent Research (IJLEMR) Volue 3 - Issue 3 March 218 PP Increasing the acceleration due to the increasing of blast explosion and decreasing the thickness of doe structure. Maxiu acceleration is developed in 1 tonne explosion of pulse loading history in the doe structure with iniu thickness of 1. REFERENCES Journal Papers: [1] Manav Patel and Dr. V. R. Panchal (217), Developent of shock spectra for different pulse shapes using C sharp International Conference on Research and Innovations in Science, Engineering & Technology, pp [2] J.A.Abdalla and A.S.Mohaed (28), Dynaic characteristics of large reinforced concrete does The 14 th World Conference on Earthquake Engineering, Beijing, China. [3] Anil Kuar (214), Effect of daping on shock spectra of ipulse loads International Journal of Scientific & Engineering Research, Volue, Issue, ISSN , pp [4] Galawezh Saber and Ghaedan Hussein (213), Analysis and optiu design of curved roof structures 2 nd International Balkans Conference on Challenges of Civil Engineering, BCCCE, pp [] EuripidisMistakidis (214), Construction of the steel doe of the ultipurpose al-sadd sports hall in Doha, Qatar AKTOR S.A.P.O. Box 3718, Doha, Qatar. [] Ms. M.A.Jain (21), Paraetric Study of Doe International Journal for Scientific Research & Developent, vol. 4, pp Panchal, V. R. and Jangid, R. S. (27), Variable friction pendulu syste for seisic isolation of liquid storage tanks, Nuclear Engineering and Design, Vol. 238, pp [7] Anuj Chandiwala (214), Analysis and Design of Steel Doe Using Software International Journal of Research in Engineering and Technology, Eissn: , pissn: , pp [8] Nelson La and priyanmendis (24), Response spectru solution for blast loading Electronic Journal of Structural Engineering, volue 4, pp [9] Zubair Ian Syed (21), Effect of large negative phase of blast loading on structural response of RC eleents MATEC Web of Conferences, Owned by the authors, published by EDP Sciences, pp.1-8. [1] Shaik Tahaseen (21), Reinforced Ceent Concrete (RCC) Doe Design International Journal of Civil and Structural Engineering Research, vol. 3, pp Page