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New Delhi, India

Saxena N.,CSIR - Central Electrochemical Research Institute | Paul D.K.,Indian Institute of Technology Roorkee | Kumar R.,CRRI
Nuclear Engineering and Design | Year: 2011

The seismic soil-structure interaction response of a nuclear reactor building requires modeling of the soil-structure interface. It allows slip and separation at the interface that affects the behavior and response of the reactor. The joint elements used to model the soil-structure interface, require incorporation of appropriate joint stiffness so that slip and separation phenomena take place under the warranted conditions. This slip and separation causes change in the response of the structure. This paper duly addresses the related aspects through comparative study of responses and draws important conclusions useful for design of nuclear reactor building. © 2010 Elsevier B.V. All rights reserved.

Chauhan S.K.,Central Road Research Institute | Sharma S.,CRRI | Shukla A.,Central Road Research Institute | Gangopadhyay S.,Central Road Research Institute
Environmental Science and Pollution Research | Year: 2010

Bitumen is a black, thermoplastic, hydrocarbon material derived from the processing of crude oil. At ambient temperature, bitumen is solid and does not present any health/environmental risks. This is one of the main reasons that bitumen is widely used for road construction all over the world. But during manufacturing/modification according to its application, storage, transportation, and use of bitumen is heated giving off various hydrocarbons emissions. In recent years, there has been increasing interest in investigating the potential of bitumen emissions to cause health effects. This is mainly because of the reason that bitumen has small amount of poly-aromatic hydrocarbons, along with some other volatiles like benzene, toluene, etc., which are known to be carcinogenic in nature. Thus, assessment of the emission characteristics and health hazards of bitumen fumes may have far reaching industrial economic and public health implications. In this review, we will discuss about the emission characteristics from bitumen, asphalts, or road construction, which is mainly contributed by bitumen fumes. Sampling strategies and analytical methods employed are also described briefly. © 2010 Springer-Verlag.

Kumar R.,CRRI | Kumar R.,University of Wisconsin - Milwaukee | Naik T.R.,University of Wisconsin - Milwaukee
2nd International Conference on Sustainable Construction Materials and Technologies | Year: 2010

Concrete is a long-lasting and less energy consuming construction material than steel and Aluminum. However, the concrete industry is the single largest consumer of natural resources. Several places around the world are facing faster rates of depletion of the resources needed for the manufacturing of portland cement, mining of aggregates, and water for making concrete. Each one of these materials has some environmental impact and, therefore, it gives rise to the sustainability issue. Further, manufacturing of the key constituent of concrete (portland cement) is one of the major emitter of the greenhouse gases, leading to global warming. Concrete provides ample opportunity for judicious use of industrial by-products and recycled materials in its manufacture resulting in numerous technical and environmental advantages leading to sustainability. This paper discusses recycling of industrial and post-consumer by-products combined with recent development in concrete technology for producing concrete as a sustainable construction material.

Alam P.,Jammu University | Ahmad K.,Jamia Millia Islamia University | Afsar S.S.,Jamia Millia Islamia University | Akhtar N.,CRRI | Raina Y.M.,Jammu University
International Journal of Structural Engineering | Year: 2015

The damage to flyovers caused by increasing traffic in last decade has demonstrated the need to assess the vibration on existing flyovers built before the advent of modern seismic design codes. The present study aims at the measurement of traffic flow and vibration characteristics on five different flyovers in Delhi (NCR). The traffic count was conducted manually; however, vibration characteristics of each flyover have been investigated using tri-axial accelerometer. The vibrations produced in flyovers have been recorded in all directions of space (X, Y, Z). Results show that vibrations produced in Panchsheel flyover have maximum vibration, (110.1 dB, 105.2 dB, and 113.2 dB) in X, Y, Z directions respectively, whereas Chirag Delhi flyover have minimum vibrations in all the three directions, i.e., (74.3 dB, 73.4 dB, 74.5 dB). All four flyovers were coated with bitumen or asphalt and their spans were shorter as well, which helped in resisting vibrational shocks. Besides being too long panchsheel flyover may be due to its girder type construction and having no bituminous or asphalt coating as well as very large span, which helps in resisting the vibrational shocks. Copyright © 2015 Inderscience Enterprises Ltd.

Bhagwan J.,CRRI | Rao P.J.,CRRI | Gangopadhyay S.,Central Road Research Institute
14th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering | Year: 2011

Construction of highways on soft ground has always posed difficulties to the construction agencies and the need to ensure a high level of performance from such embankments and has always been one of the main areas of research at Central Road Research Institute, New Delhi. A number of semi-field experiments were carried out by the Institute to develop and evaluate appropriate ground improvement techniques like use of stone columns, application of geotextiles, use of different kinds of vertical drains, stabilisation of soils using admixtures etc. Some of the failures in roads were also investigated and remedial measures to improve the existing roads were also proposed. Design of embankment for Eastern Freeway, about 4.5 km of which was passing through marine clay / marshy zone adjoining creek area in Mumbai, was investigated by CRRI. The investigations were carried out in the field to get sub-soil profile and in-situ strength characteristics. Disturbed as well as undisturbed samples were collected to study the different aspects in the laboratory. The present paper is intended to highlight the findings of these investigations.

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