Abstract

Magnitudes that have the epicentrical distance from7 to 343 kilometers. The focal depth ranges from 20-100 km. The seimograms which are used in this study.

Abstract

Saturation area E and porisity paramenter using new data set recorded by the Gujarath sesmic network of India.

Abstract

day by day increasing cost of vehicle transport service for petrolium product, made pipeline as more affordable mean

Abstract

Ports are lifeline systems that function as storage and maintaning facility for the transport of cargos. The port structures are frequently exposed to failure under

Abstract

Symatically analyzied b- value variation in space as well as in time

Abstract

Ports are lifeline systems that function as storage and maintenance facilities for the transport of cargos. The port structures are frequently exposed to failure under severe seismic loading, for example, 1995 Kobe, 1989 Loma prieta, 1999 Kocaeli and 2001 Bhuj earthquakes. The scenario is more critical if the port sites are located within the seismically vulnerable area like Gujarat state of India. This clearly indicates the importance of port buildings and stability that can withstand natural disasters particularly earthquakes. The main objective of this paper is to perform the nonlinear dynamic analysis of Kandla port building subjected to ground motion. Ground motions generated by Institute of Seismological Research (ISR), Gujarat at four locations on Katrol Hill Fault (KHF) and Kachchh Mainland Fault (KMF) were used in the analysis. Finally, the damage of the Kandla port building is estimated though fragility curves. The damage values obtained from fragility curve are 0.46, 0.17 and 0.88 for KHF Mandvi, NKF Jodiya and KMF Jhangi ground motions respectively.

Abstract

Masonry is one of the most common types of construction materials in India. It is commonly used for infill walls in Ordinary Moment Resisting Frames. The strength based design in the code considers the masonry wall as non-structural element and its load is considered on the corresponding elements. The numerical modeling of infill is completely disregarded during analysis of the structure. To design a building realistically, the behaviour of all the primary components is needed and the load carrying capacities are required to be properly assessed. Apart from the strength based design adopted in the code of practice, the modern and advanced approach to design, the performance based design, needs a proper understanding of the behaviour of all the structural elements. Analytical modeling of infill is attempted by many researchers using equivalent strut and tie models which can idealize the behaviour of masonry infill to some extent. The effect of masonry wall on RC frame can be well understood by continuum modeling. Numerical modeling of masonry infill wall is done using Finite Element Method. This paper attempts to simulate the nonlinear behaviour of URM infill frames with varying storeys using Applied Element Method (ARM). Two bay ordinary moment resisting frame is considered with and without infill and capacity is obtained using Nonlinear Static Pushover analysis. One, two and three storey frames with and without openings are also analyzed to understand the differences in drift ratios and the strength of the frame. It is observed that the bare frame carries lesser drift when compared to the frame with infill. This clearly proves the increase in ductility of the frame when provided with infill. In the analyses of infill frame without door and window openings, the maximum base shear of the frame decreased and the drift carrying capacity increased with the increase in number of storeys. Almost the similar behaviour is observed when the infill frame with openings is analyzed.

Abstract

The usefulness of shear walls in the structural planning of multi-story buildings has long been recognized. When walls are situated in advantageous positions in a building, they can be very efficient in resisting lateral loads originating from wind or earthquakes. Reinforced concrete framed buildings are adequate for resisting both vertical and horizontal loads acting on them. Extensive research has been done in the design and analysis of shear wall highrise buildings. However, significance of shear wall in highrise irregular structures is not much discussed in literature. A study on an irregular highrise building with shear wall and without shear wall was studied to understand the lateral loads, story drifts and torsion effects. From the results it is inferred that shear walls are more resistant to lateral loads in an irregular structure.

Abstract

Modern research in India on dams has entered a distinct phase subsequent to the damage to Koyna dam, located in hitherto considered stable continental part, due to an earthquake on 11th December, 1967 in Koyna district, India. Out of about 5,100 large dams in India, a significant number are in moderately high and high seismic zones. As such they may be prone to probable instability to the dam’s structure due to earthquake resultant impacts. Even though none of the dams other than Koyna got damaged in India due to high magnitude earthquake activity, since 1967, it is felt necessary to understand the behaviour of dams due to water load coupled with dynamics of faults that are present in the vicinity of the dam, as dam failures due to earthquake activity are reported from different parts of the world. In this paper, damage to Koyna dam due to a fault motion caused nearby has been studied. A concrete gravity dam is selected from the National Importance Dams of India. Structure-1(S1) as a concrete gravity dam with foundation and structure-2 (S2) as a concrete gravity dam with foundation and soil strata are numerically modeled using Applied Element Method (AEM). Displacement at the base of soil strata is given to generate reverse fault effect on the dam. Behavior of dam is studied by direct and sub-structure methods. In the direct method, the effect of fault motion on dam is studied in S2, by modeling dam at different locations on foot wall and hanging wall. In sub-structure method, free-field accelerations are recorded at different locations on foot wall and hanging wall while only the sub-structure is subjected to fault motion. The recorded accelerations on the surface are used as input to analyze super structure S1. Comparison on behavior of dam in models S1 and S2 is later drawn.

Abstract

The overall capacity of a structure depends on the strength and deformation capacity of the individual components of the structure. This paper deals with the prediction of effect of a member on global performance of the structure. The performance of a 5 storey RC frame, designed for Indian standard codes has been presented. Non linear pushover analysis is used to draw the capacity curve. During the pushover analysis when the structure becomes unstable, the failed members are identified. In the present study, end columns of the bottom storey which exists in failed members are strengthened by increasing the longitudinal reinforcement, increasing the c/s area and reducing the shear reinforcement spacing. Increase of longitudinal reinforcement or decrease of shear reinforcement spacing not effected much the strength capacity, but the ductility is increased in both the cases. Increasing the c/s area of two columns increased the strength and stiffness of the frame, but the ductility is increased up to a certain limit and then decreased. Parametric study also done for individual column performance with same geometric and material properties as it exists in the frame. The performance of individual column is completely different with frame performance though the geometric and material properties are same this is because of the frame action where redistribution of forces takes place when the member fails in the frame.