Dr. Suresh R Dash | IIT Bhubaneswar (original) (raw)

Papers by Dr. Suresh R Dash

Journal of Pipeline Systems Engineering and Practice

AbstractPipelines are one of the most important lifeline facilities that play a vital role in mai... more AbstractPipelines are one of the most important lifeline facilities that play a vital role in maintaining the public safety and economic wellbeing of a nation. They traverse over a large area with ...

Pure and Applied Geophysics, 2022

The Indian peninsular region has witnessed moderate to large earthquakes in the recent past. The ... more The Indian peninsular region has witnessed moderate to large earthquakes in the recent past. The present work demonstrates probabilistic seismic hazard assessment at the bedrock level using six ground-motion prediction equations with a logic tree approach considering Odisha state as a case study. Regional rupture characteristics are established for the tectonic features of the study region. Uniform hazard response spectra are computed for district places. Seismic hazard results are disaggregated for Bhubaneswar, the capital city of Odisha. The results have shown the distribution of seismicity in the state is not in sync with the seismic zone map provided by the Indian code.

Advances in Numerical Methods in Geotechnical Engineering, 2018

The technique of constructing a p-y curve relies upon the similarity between load-deformation cha... more The technique of constructing a p-y curve relies upon the similarity between load-deformation characteristics of pile with the stress-strain behavior of the interacting soil as observed in many recent experimental studies. From a dimensional analogy of pile-soil interaction with flow type strain field, the strain distribution in soil due to pile deflection (y) can be considered proportional to the y/D ratio, where D is the diameter of the pile. When the depth of the construction is deep, the pile-soil interaction can be considered as a plain strain model. To obtain the p-y curve from stress-strain curve, scaling factors such as Ms and Ns are normally used. Although these scaling factors are well calibrated and are being used in practice since long for standard soil, its applicability and values for liquefied soil is very limited. This paper provides a simplified methodology of developing these scaling factors suitable for liquefiable soils by using a numerical procedure with virtual work principle.

Journal of Transportation Engineering, Part B: Pavements, 2020

AbstractGranular lateritic soils (GLS) are available in many parts of the world as a marginal mat... more AbstractGranular lateritic soils (GLS) are available in many parts of the world as a marginal material, which can be stabilized and used as cemented subbase/base layers in pavements. Fatigue charac...

Pipelines are the most reliable, economic and efficient means for the transportation of water and... more Pipelines are the most reliable, economic and efficient means for the transportation of water and other commercial fluids such as oil and gas. Pipeline systems can be designated as lifelines as their operation is essential in maintaining the public safety and well-being even after a natural disaster like earthquakes. A pipeline system traverses a large geographical area, and soil conditions thus, is susceptible to a wide variety of seismic hazards such as ruptures or severe distortions associated with relative motion arising from fault movements, landslides, liquefaction, loss of support, or differential motion at abrupt interfaces between rock and soil. Notably the most catastrophic damages are the once resulting from faulting and liquefaction. Owing to these facts, the performance of buried and above ground pipelines subjected to faulting and soil liquefaction effect and other seismic hazards is of great concern. This paper discusses in detail the techniques that are implemented f...

Pile foundations are one of the most preferred deep foundation systems for high rise or heavily l... more Pile foundations are one of the most preferred deep foundation systems for high rise or heavily loaded structures. In many instances, the failure of the pile founded structures in liquefiable soils had been observed even in many recent earthquakes. Failure of pile foundation have occurred because of buckling, as the pile behaves as an unsupported slender structural element once the surrounding soil liquefies. However, the buckling capacity depends on the depth of soil liquefied and its residual strength. Hence it is essential to check the pile against the possible buckling failure. Beam on non-linear Winkler Foundation is one of the efficient methods to model the pile-soil behavior in liquefiable soil. The pile-soil interaction is modelled through p-y springs, there are different p-y curves available for modeling liquefiable soil. In the present work, the influence of two such p-y curves on the buckling capacity of pile foundation is studied considering the initial geometric and non...

International Journal of Geomate, 2015

The degree of liquefaction as characterised by the excess pore water pressure plays an important ... more The degree of liquefaction as characterised by the excess pore water pressure plays an important role in defining soil strength and stiffness. The pile-soil interaction in liquefiable soil, if modelled using BNWF model, the strength and stiffness of the soil springs can be suitably reduced by using a reduction factor. This reduction mainly depends on the soil type, its SPT/CPT value and the degree of liquefaction. Ideally this reduction should be based on the excess pore water pressure near the pile. However, it is difficult to estimate the degree of liquefaction near the pile. Hence, the lateral resistance of liquefied soil at soil-pile interface is normally characterized by the degree of liquefaction expected in the soil at the site without considering the influence of pile. Though, excess pore pressure near to the pile could be the governing parameter of soil resistance, it is hard to characterize the expected value of it in a field condition, as it depends on many parameters including soil type, shear loading, pile dimension, gap formation near to pile that facilitates easy dissipation of excess pore water pressure (EPWP), soil densification during pile driving, etc. Hence, to understand the difference between the far- field and near-pile response of liquefied soil, one high quality centrifuge test results are studied in this paper. The pattern of excess pore water pressure generation and development has been compared for both near-pile and far- field. The results are critically reviewed and discussed in this paper.

Lecture Notes in Civil Engineering, 2019

Pile foundations are often preferred in high seismic zones; however, even having high factor of s... more Pile foundations are often preferred in high seismic zones; however, even having high factor of safety against bending strength many historic evidences showed that pile foundations are vulnerable during earthquakes, especially when liquefaction occurs. Major code specification treats pile as beam element subjected to lateral loading, and no definitive provisions are available on analysis method for pile foundation embedded in alternate liquefiable and non-liquefiable soil. The present study is conducted to model layered liquefiable soils for pile foundation response considering state-of-the-art understating along with available code recommendations. Both force-based and displacement-based approaches for typical layered soil profile were chosen in this study. The soil liquefaction depth of the middle layer was varied to understand the behavior during successive stages of liquefaction. The pile-soil interaction was modeled through p-y lateral springs, and suitable reduction was made f...

Lecture Notes in Civil Engineering, 2020

Partial infill frames are constructed by filling the bare frame with brick masonry to a certain h... more Partial infill frames are constructed by filling the bare frame with brick masonry to a certain height throughout the length of the frame. The walls generally restrain a part of the column to deform freely and a leftover portion remains captive which attracts large shear force and shows brittle failure (called captive column failure) during an earthquake, often leading to collapse of the building. Although sufficient experimental investigation has been carried out for infill walls with openings, the same for partial infill frame and recommendations for its modelling in building frame analysis are very limited. This paper collates the performances of partial infill RC frames during major past earthquakes and attempts to provide a review of the major literature on the performance of partial infill frames studied through experiments and numerical models, and their simplified analytical formulations. Further, some available methods to prevent captive column effect are also presented in this paper. The performance of retrofitted partial infill frames, which previously failed due to the captive column effect, studied experimentally by other researchers are also summarised.

Journal of Earthquake Engineering, 2020

A major limitation with conventional post-tensioned (PT) shear wall in seismic areas is its low e... more A major limitation with conventional post-tensioned (PT) shear wall in seismic areas is its low energy dissipation, which is tackled by placing additional mild steel reinforcement at the intersection of the wall and the foundation, called internal energy dissipating reinforcement (EDR). While the behavior of hybrid walls with internal EDR is satisfactory, the replacement of them postyielding (i.e., after an earthquake) poses a major concern. Therefore, in this study, a new simple arrangement is proposed with external-energydissipating-reinforcement (EEDR) to facilitate its easy placement and replacement. This proposed system is expected to enable convenient rehabilitation of the wall after an earthquake and will keep it ready for next seismic shock. A detailed numerical study has been conducted to examine the feasibility of the proposed configuration. The proposed model depicts rocking behaviour with sufficient self-centering and energy dissipation. Having external EDR in the hybrid PT shear wall resulted in an increase in energy dissipation but keeping the strength and stiffness of the wall nearly unaffected. This study has highlighted the effectiveness of proposed external EDR system without significantly compromising the performance of a hybrid PT shear wall during an earthquake.

International Journal of Pavement Engineering, 2018

Cement stabilised materials are increasingly being used in pavement structural layers to solve th... more Cement stabilised materials are increasingly being used in pavement structural layers to solve the issue of scarcity of good quality stone aggregates and also to enhance the performance of the pavement. In addition to the strength and stiffness, the performance of pavements layers also largely depends upon the durability and shrinkage characteristics of stabilised materials used as base and subbase layers. The research reported in this paper focuses on the laboratory durability and shrinkage characteristics of cement stabilised granular lateritic soils (CLS). Wet-Dry (W-D) durability test and soaked UCS tests were conducted on CLS samples to evaluate the minimum dosage requirement of the binder. Preliminary studies were also done to assess the water absorption characteristics of CLS. Shrinkage properties of CLS were assessed through drying shrinkage tests. Effect of moisture content and cement content on ultimate drying shrinkage was also established in this study.

Journal of Performance of Constructed Facilities, 2018

AbstractPipelines are lifeline structures, as any significant disruption to the performance of th... more AbstractPipelines are lifeline structures, as any significant disruption to the performance of these systems often translates into undesirable impacts on the economics and the living conditions of ...

Géotechnique, 2017

In practice, laterally loaded piles are most often analysed using a ‘beam-on-non-linear-Winkler-f... more In practice, laterally loaded piles are most often analysed using a ‘beam-on-non-linear-Winkler-foundation’ approach, whereby the soil–structure interaction is modelled by means of p–y curves. Although well-calibrated p–y curves exist for non-liquefied soils (e.g. soft clay and sand), the profession still lacks reliable p–y curves for liquefied soils. In fact, the latter should be consistent with the observed strain-stiffening behaviour exhibited by liquefied samples in both element and physical model tests. It is recognised that this behaviour is induced by the tendency of the liquefied soil to dilate upon undrained shearing, which ultimately results in a gradual decrease in excess pore pressure, and consequent increase in stiffness and strength. The aim of this paper is twofold. First, it proposes an easy-to-use empirical model for constructing stress–strain relationships for liquefied soils. This only requires three soil parameters which can conveniently be determined by means of...

Soil Dynamics and Earthquake Engineering, 2009

A case study is presented of the interaction between the bending due to laterally spreading force... more A case study is presented of the interaction between the bending due to laterally spreading forces and axial-load induced settlement on the piled foundations of the Kandla Port and Customs Tower located in Kandla Port, India, during the 2001 Bhuj earthquake. The 22 m tall tower had ...

Soil Dynamics and Earthquake Engineering, 2010

... The ensuing large deflection of the beam may then induce plasticity in the beam resulting in ... more ... The ensuing large deflection of the beam may then induce plasticity in the beam resulting in an early failure. Keeping the design procedure in mind, this interaction of lateral and axialload on piles can be referred to as bendingbuckling interaction. Fig. ...

Soil Testing, Soil Stability and Ground Improvement, 2017

A huge network of rural roads is being developed in India under the most ambitious Prime Minister... more A huge network of rural roads is being developed in India under the most ambitious Prime Minister's rural connectivity programme, PMGSY (Pradhan Mantri Gramin Sadak Yojna). Under this programme, thousands of kilometers of rural roads are being constructed in the country, which require good quality pavement materials like crushed stone. The scarcity of natural aggregates has compelled to use marginal materials or locally available soils in structural layers of these pavements, which would reduced the cost of the project. Granular lateritic soils are widely available in many parts of India and presently, this is also used as sub-base material in different rural road projects, where it satisfies the code specifications. However, granular lateritic soils of some locations do not satisfy the strength and plasticity requirement of sub-base layer. But, they can probably be made suitable through stabilization. Though stabilization of soil by cement or lime is a well known process of improving the strength and stability of soil, the strength and stiffness parameters of stabilized lateritic soils in terms of modulus of rupture, resilient modulus, flexural modulus have very limited reference in literature. Therefore, in this study an attempt has been made to characterize the cement stabilized lateritic soils for use in sub-base and base layers in rural road pavements. A comprehensive laboratory testing programme has been conducted on cement stabilized granular lateritic soil samples collected from five different places of eastern India to study various strength parameters such as compressive strength, modulus of rupture and stiffness properties in terms of flexural modulus of cement stabilized granular lateritic soil. In this paper, strength and stiffness developments of cement stabilized granular lateritic soil in 7 days and 28 days have been studied and its suitability as a structural layer in rural roads has been investigated. Suitable modulus values of cement stabilized granular lateritic soils have been proposed which can be used as an input parameter for the input in mechanistic design of roads. Also relationships have been proposed to determine modulus of rupture and flexural modulus of cement stabilized granular lateritic soil from its compressive strengths.

Collapse and/or severe damage to pile-supported structures are still observed in liquefiable soil... more Collapse and/or severe damage to pile-supported structures are still observed in liquefiable soils after most major earthquakes. Therefore this remains a great concern to the earthquake engineering community. This paper critically reviews the current understanding of pile failure in seismically liquefiable soils. The plausible failure mechanisms of these foundations that have been identified so far are summarised. Essential criteria for design of pile foundations have been proposed.