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Analysis and design of prestressed concrete box girder bridge

By
Miss.P.R. Bhivgade

Abstract:– Bridge construction today has achieved a worldwide level of importance. Bridges are the key elements in any road network Use of box girder is gaining popularity in bridge engineering fraternity because of its better stability, serviceability, economy, aesthetic appearance and structural efficiency. The structural behavior of box girder is complicated, which is difficult to analyze in its actual conditions by conventional methods. In present study a two lane simply supported Box Girder Bridge made up of prestressed concrete which is analysis for moving loads as per Indian Road Congress (IRC:6) recommendations, Prestressed Code (IS: 1343) and also as per IRC: 18 specifications. The analyzed of box girder using SAP 2000 14 Bridge Wizard and prestressed with parabolic tendons in which utilize full section. The various span/ depth ratio considered to get the proportioning depth at which stresses criteria and deflection criteria get satisfied.

Keywords: Concrete Box Girder Bridge, Prestress Force, Eccentricity, Prestress Losses, Reinforcement, Flexure strength, shear strength, SAP Model.

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Mitigation of Soil Erosion with Jute Geotextile Aided by Vegetation Cover

Mitigation of Soil Erosion with Jute Geotextile Aided by Vegetation Cover: Optimization of an Integrated Tactic for Sustainable Soil Conservation System (SSCS)
By Md Minhaz Mahmud, Nazmul Huda Chowdhury, Md Manjur Elahi, Md Hasanur Rashid, Md Kamrul Hasan
Khulna University of Engineering & Technology(KUET), Khulna, Bangladesh

Abstract
Degradation of soil considered as one of the foremost vulnerability and global threats nowadays not only for agricultural production and food security, but also for the environmental challenges related to watershed protection, disaster management, bio-diversity conservation, sustainable management of natural resources and climate change, furthermore, complication in Civil engineering. In Bangladesh where arable lands are less than necessary, certainly susceptible to severe erosion due to rainfall and flood, particularly when poor agricultural methods are used or preventive measures are not taken. Implementation of Jute Geotextiles (JGT) aided by native vegetation cover was investigated intended to design a sustainable and low cost tactic at Beel Dakatia through the entire year of 2009. Prime consequences were that erosion, moisture content and runoff are likely to be considerably impacted by rainfall intensity, soil surface slope; additionally, combined presence of JGT and vegetation cover reduced rate of erosion about 95% and runoff about 70% with respect to bare plots. Hence, play noteworthy role to conserve soil and stabilize the slope as well and mitigate susceptibility to degradation.

Keywords : Soil Protection, Jute Geotextiles (JGT), Watershed Management, Renewable Natural Resource, Disaster Management, Soil Strength.
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Structural Design of a Bus Terminal

By
MD Anamul Hasan

Abstract
Bus-terminal is an essential component of urban transport facilities which defines the beginning (origin) or end (terminating) of the line for the transportation system. It normally requires a size-able land in a strategic part of an urban area. A well planned or managed bus-terminal will act as catalyst to the social and economic development of the surrounding areas. On the other hand, bus-terminal is an asset to an area as it may act as catalyst to economic and social development of the surrounding areas. However, poorly planned and sited terminal for buses may generate traffic problems as well as deteriorating the quality of life of the affected surroundings. This project focuses mainly the structural design of whole bus terminal. As with engineering and operational aspects of terminal facilities the focus would be on the design to fulfill traffic capacity requirement and operational efficiency to operators and passengers. The proposed far side terminating bas terminal model which located outside city centre may have added advantages such as reducing unnecessary congestion and improving the environment.

Objectives: This project have following main objectives:
Conducting research on the existing bus terminal of a city and proposing a new model of bus
terminal according to findings
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Visual Inspection of Concrete Structure

By
Kaushal Kishore
Materials Engineer, Roorkee

Visual inspection is one of the most versatile and powerful of the NDT methods, and it is typically one of the first steps in the evaluation of a concrete structure. Visual inspection can provide a wealth of information that may lead to positive identification of the cause of observed distress. However, its effectiveness depends on the knowledge and experience of the investigator. Broad knowledge in structural engineering, concrete materials, and construction methods is needed to extract the most information from visual inspection.

Before performing a detailed visual inspection, the investigator should develop and follow a definite plan to maximize the quality of the record data. Visual inspection has the obvious limitation that only visible surface can be inspected. Internal defects go unnoticed and no quantitative information is obtained about the properties of the concrete. For these reasons, a visual inspection is usually supplemented by one or more of the other NDT methods, such as by concrete test hammer, ultrasonic concrete tester and partial destructive testing by drilling cores and testing them for compressive strength.
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Properties Of Green Lightweight Aggregate Concrete

By
Ali Shokati Sayyad, MS Student Of Islamic Azad University Chaloos Branch Kooros
Nekoofar Asisatant Professor Of Islamic Azad University Chaloos Branch

Abstract
With increasing concern over the excessive exploitation of natural aggregates, synthetic lightweight aggregate produced from environmental waste is a viable new source of structural aggregate material. The uses of structural grade lightweight concrete reduce considerably the self-load of a structure and permit larger precast units to be handled. In this paper, the mechanical properties of a structural grade lightweight aggregate made with fly ash and clay will be presented. The findings indicated that water absorption of the green aggregate is large but the crushing strength of the resulting concrete can be high. The 28-day cube compressive strength of the resulting lightweight aggregate concrete with density of 1590 kg/m3 and respective strength of 34 MPa. Experience of utilizing the green lightweight aggregate concrete in prefabrication of concrete elements is also discussed.
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