A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Ravi Sekhar, Ch.
- On-Site Visualization Monitoring for Long Span Bridge on Delhi Metro Project
Authors
1 Oriental Consultant Ltd, Tokyo, JP
2 Department of Civil Engineering, Kobe University, JP
3 Transportation Planning Division, CSIR-Central Road Research Institute, New Delhi 110 025, IN
4 Design and Planning Department, Delhi Metro Rail Corporation Ltd, New Delhi 110 003, IN
5 AKEBONO Brake Industry, Tokyo, JP
Source
Current Science, Vol 106, No 9 (2014), Pagination: 1280-1290Abstract
A new monitoring scheme, based on the concept of onsite visualization (OSV), was successfully applied for monitoring safety conditions during construction of a long span cantilever bridge in Delhi Metro Phase-II project in 2010. The bridge construction with challenging features included a 100 m long span over the Northern Railways tracks passing below, the balanced cantilever construction methodology with a see-saw condition of the pin-connected girder during segment casting processes and a horizontal curvature of the girder with 300 m radius. The light-emitting sensors with dual functions, namely sensing and simultaneous visual output of measured results, were employed in this project and played crucial roles to capture unique behaviours of the bridge under construction and to ensure safety throughout the project.Keywords
Balanced Cantilever Construction, Laser Pointer, Long Span Bridge, On-Site Visualization.- Ree Geochemistry of Monazites from Coastal Sands between Bhimunipatnam and Konada, Andhra Pradesh, East Coast of India
Authors
1 Department of Geology, Andhra University, Visakhapatnam 530 003, IN
Source
Current Science, Vol 110, No 8 (2016), Pagination: 1550-1559Abstract
The rare earth elements (REE) geochemistry of monazites of Bhimunipatnam-Konada coastal sand deposit was studied using EPMA method. The average LREE concentration was 53.31%, which is more than HREE (av 1.38%)ΣLREE more than actinides (Th + U) indicates that provenance for monazite in the study area is garnet-bearing paragenesis rocks such as charnockites and metapelitic rock (khondalite). The REE fractionation patterns and positive europium anomalies indicate that monazites were formed from magma/ anatectic melt with high oxygen fugacity. The U-Th- Pb geochemical dating of monazites is 1000 Ma (average), which indicates that they are derived from protoliths of charnockites and metapelitic rocks such as khondalites, which are formed during meso-neo- Proterozoic ages in the Eastern Ghats Granulite Belt.Keywords
Coastal Sand Deposits, Geochemical Dating, Khondalites, Monazites, Rare Earth Elements.- Route Performance Evaluation of a Closed Bus Rapid Transit System Using GPS Data
Authors
1 Department of Civil Engineering, Indian Institute of Technology, Roorkee 247 667, IN
2 Transportation Planning Division, CSIR-Central Road Research Institute, New Delhi 110 025, IN
Source
Current Science, Vol 112, No 08 (2017), Pagination: 1642-1652Abstract
GPS-fitted buses operating in bus rapid transit systems (BRTS) of India make it easier to collect a wealth of travel-time data from them. This article evaluates the operational performance of BRTS routes based on GPS data. First, various simplified statistical range parameters, viz. coefficient of variation percentile travel time, travel-time distributions, etc. are selected for route evaluation. Then, two bus routes of the Ahmedabad BRTS are selected as case study to develop and validate a methodology for evaluating the performance of these routes based on selected parameters. Weekday bus travel-time data for one direction accounting for 2124 bus trips are used in the study. The study then compares travel-time reliability-based performance of a BRT and a non-BRT route. Further, the study proposes an approach to measure a shift in BRTS network level of service based on two indices - average travel time per kilometre, and travel-time coefficient of variation. A left shift in cumulative plot indicates an improvement in the BRTS network level of service in the year 2016 compared to 2013.
Keywords
Bus Rapid Transit Systems, GPS Data, Route Performance, Statistical Parameters.References
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