CIVIL ENGG. Volume:91 2011 FEB

Srl	PDF	ARTICLE NAME	ABSTRACT
1		GIS and PCA based Risk Generation in Traffic Mobility in Urban Areas	Risk generation in traffic mobility using PCA and GIS is conducted with the objective of knowing the exact criteria and the links which lead to congestion. The Quthbullapur municipality of Ranga Reddy district, Andhra Pradesh, has been delineated as the study area. Road network characterization surveys and traffic characterization surveys are conducted in the study area. Travel demand analysis is done using GIS where desire line diagrams, user preferred paths and the functionality of road system have been identified. Identifying congestion in the links of the network is an important task in integrated planning.The performance and functionality of a link can be attributed to many characteristics including the neighbourhood characteristics of the link and there is a research gap in finding the exact criterions which are the real factors of risk generation. So the link has to be evaluated based on these conflicting multi attributes at one point of time. Risk analysis has been done through principal component analysis followed by regression analysis to identify the factors contributing to risk generation and the major links which are leading to congestion.
2		Seismic Pure Friction base Isolation Performance using Demolished Waste in Two-storey Masonry Building	Pure friction isolation technique can be adopted economically in developing countries where low-rise building prevails due to their low cost. In this type of base isolation technique, a clear smoothened surface is created at the plinth level of a two- storey masonry building and the super structure rests at this level to slide freely, except for frictional resistance. Two 1:4 scale two-storey brick model were constructed using 20 % demolished waste as fine aggregate in the mortar replacing cement by weight, on the shake table for dynamic testing for two different friction isolation materials, ie,Teflon (µ = 0.29) and coarse dry sand (µ = 0.36). The structure was separated from the foundation at plinth level, so as to permit sliding of superstructure during testing. An analytical model has also been developed, for this brick building having two mass, spring and dash-pot systems. The observed values of acceleration response of the two models tested with Teflon and coarse dry sand are comparable with the corresponding values of the analytical model.The whole study clearly shows the reduction of response of the sliding system as compared to the response of conventional building. It was observed that the two-storey model with Teflon as a friction isolation material performed better and resisted almost three times the table force as compared to the model with sand as isolation material. Further it was also found that complete sliding of model with dry sand as a friction isolation material, took place at 4.25 kN table force whereas the model with Teflon as a friction isolation material, it was at a table force of 14.3 kN. The present work also concludes that the use of the demolished waste replacing cement in the mortar can be adopted safely and economically as a supplementary building material. A 20% replacement of the cement by demolished waste in the mortar has been safely adopted for constructing a two-storey clay brick masonry building without endangering the seismic safety of the structure.
3		Effect of Crude Oil on Some Properties of Clayey Soil of High Compressibility	The study has been carried out with two broad objectives — to observe the effect of crude oil contamination on some properties of soil and to predict the change in the properties quantitatively in the form of mathematical correlation. Naturally available clayey soil of high compressibility (CH) was used for this study. Laboratory tests were conducted on uncontaminated soil samples and soil samples contaminated at different level of contamination.Mathematical correlation between the soil property and the level of contamination was determined by using statistical methods. Change in liquid limit, plastic limit, unconfined compressive strength and differential free swell index of crude oil contaminated was observed. Liquid limit decreases linearly whereas unconfined compressive strength decreases parabolically with increase in the level of crude oil contamination. Differential Free Swell Index increases parabolically. Change in plastic limit is not significant.
4		Seepage Characteristics and Collapse Behaviour Study of Fly Ash from Ahmedabad	In this experimental work, the efforts are made to determine the engineering properties, seepage characteristics and collapse potential of fly ash collected from Ahmedabad, a city in the western India in Gujarat state. The co efficient of permeability of torrent power and Gujarat Electricity Board (GEB) fly ashes are found to be 1.16 × 10 – 6 m/s and 1.25 × 10 – 7 m/s, respectively and of soil is 3.87 × 10 –6 m/s.Addition of horizontal soil layer reduces the coefficient of permeability of fly ash soil mix. From oedometer tests on the fly ash samples it is observed that the maximum collapse potential for torrent power and GEB fly ash are 0.023 and 0.027, respectively. It is also concluded that there is very little risk of collapse of both fly ash over a wide range of stress. The material can be used for geotechnical applications.
5		Graphical Method to Obtain Dynamic Passive Earth Pressure of Rigid Retaining Wall Supporting c - F Backfill	The study presents a rational graphical approach to obtain the dynamic passive earth pressure on inclined retaining wall having inclined backfill along with surcharge load acting over backfill possessing both cohesion and adhesion.Pseudo-static analysis is carried out to obtain the dynamic passive earth pressure and instead of considering cohesion and adhesion of same magnitude, they can be considered of different magnitudes. Here in this analysis, the critical wedge angle is a single one irrespective of weight, surcharge and cohesion and this fact is also more realistic.
6		A New Device to Apply Repetitive Loading to Soil Sample	A new but simple device to apply repetitive loading to soil sample has been developed by modifying the existing triaxial test set up. The top cover has been replaced with a modified one to accommodate a loading plunger of diameter equal to the diameter of the soil sample.Due to this modification, the cell pressure can be varied without affecting the axial stress and thus tension can be developed in the sample. The new device has been discussed in detail and the representative test results have been presented to show the usefulness of the modification.
7		Monitoring Crustal Deformation of Western Maharashtra Peninsular Shield of India using GPS	The paper gives a broad overview of how GPS can be used to estimate the deformation along the seismic prone Western Maharashtra Peninsular shield of India. Indian Institute of Technology Bombay in collaboration with Indian Institute of Geomagnetism Mumbai was actively working in the field of crustal deformation monitoring along Western Maharashtra. An extensive GPS network had been established for this purpose, periodically observed for two campaigns, May 2004 and October 2004, and analysed thoroughly.To understand the pattern of crustal movement along Western Maharashtra during the period of study, the magnitude and direction of deformations of the regional network was estimated. These GPS-estimated deformations were thereby used as an indicator to identify regions of stress build-up and the reliability of the analysis was confirmed with real seismic data collected. The analysis showed the regions of reservoir triggered seismicity, Koyna and Warna were stressed during the period of study.
8		Use of Waste Human Hair as Fibre Reinforcement in Concrete	Reinforcement by fibres can offer a convenient, practical and economical method of overcoming many deficiencies. Hair fibre an alternative non-degradable fibre is available in abundance which creates environmental problem similar to Fly Ash (FA). To see the effect of human hair fibre on compressive, crushing strength and cracking control to economise concrete, and reduction of environmental problems, the present study has been undertaken.Experiments were conducted on concrete prisms with varying percentage of Human Hair Fibre (HHF), ie, 0%, 1%, 1.5%, 2% and 2.5% by weight of cement. Next, in the plain concrete, cement has been replaced with 10% fly ash by weight and same HHF percentage variations were used to make Hair Fibre Reinforced Fly Ash Concrete (HFRFAC). Afterwards, in HFRFAC 6% brick powder was added further to make Hair Fibre Reinforced Fly Ash Brick Powder Concrete (HFRFABC). Further, the HFRFAC was mixed 1.5% lime powder to make Hair Fibre Reinforced Fly Ash Lime Powder Concrete (HFRFALC). For each combination, three cubes were tested for their properties. The result shows that there is encouragable enhancement in its mechanical properties investigated with the addition of human hair fibres. Maximum strength has been obtained in the lime combination case with 2% HHF addition.