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Research Papers

Testing of Concrete Blocks

By
Er. Kaushal Kishore ,
Materials Engineer, Roorkee

INTRODUCTION
Concrete can be converted into precast masonry units such as Hollow and Solid normal and light weight concrete blocks of suitable size to be used for load and non-load bearing units for wallings. Use of such concrete blocks are more appropriate in region where soil bricks are costly, poor in strength and are not available. Depending upon the structural requirements of masonry unit, concrete mixes can be designed using ingredients available locally or if not found suitable then with in the most economical distance. The concrete mix used for normal hollow and solid blocks shall not be richer than one part by volume of cement to 6 parts by volume of combined room dry aggregates before mixing. Hollow concrete blocks for normal work used in masonry when reinforced is used shall not be leaner than 1 part cement to 8 parts room dry sand by volume. The mixes are designed with the available materials to give overall economy and the required properties of the products. The hollow load bearing concrete blocks of the standard size 400 x 200 x 200 mm will weight between 17 and 26 kg (1063 to 1625 kg/m3) when made with normal weight aggregates. Normal weight blocks are made with cement, sand, gravel, crushed stone and air-cooled slag. The grading for sand used in Hollow concrete block shall be as given below:
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Design of Substructure Bridge with Different Codes and Analysis the Data for Settlement and Bearing Capacity Manually and by Using Plaxiz 3D Program of Finite Elements

Abstract
This paper discussed the design of substructure of bridge subjected to load of train with using two codes, the first code is AASHTO code and the second is the Chinese Code. This study focuses on the substructure of the bridge design and the design manually with the two codes.

By the design of the Bridge using the codes above, we found that Chinese Code is more safely that the number of reinforcement bars more in the pile cap and pile.

Settlement of the bridge also is calculated by using the data collected from the project site, the vertical ultimate bearing capacity of pile group and the dynamic action of the train loads, by this study it can be concluded all the above are safe values.

Another analysis by using the three-dimensional Plaxis program of finite elements and many parameters calculated, the value of the maximum vertical displacement was near from the calculated value which gives another checking for the design and maintain the safe conditions for the Bridge.

1. Introduction
Many of codes used in the world for design the bridges and many of countries have special codes for design depending on the specialty of that country and the nature, environmental conditions, effect of earth quakes etc. In the United States Bridge Engineers use AASHTO’s standard Specification for Highway Bridges and, in similar fashion or trends, German bridge engineer utilize the DIN standard and British use the BS 5400 code. In general, countries like German and United Kingdom which have developed and maintained major highway systems for a great many years possess their own national bridge standards. The AASHTO Standard Specification, however, have been accepted by many countries as the general code by which bridges should be designed.

In this paper, the design of a bridge by using two codes the AASHTO and Chinese codes. The AASHTO Code for design bridges named “American Association of State Highway and Transportation
Officials.”

In China there are many codes for design about 81 codes for design for all the majors in the civil engineering with serial numbers of standard, the code used for this study is (The Chinese National Standard (CNS, 2002)) [4], Building Foundation Design Code (GB50007-2002). The Chinese Codes for design bridges focusing on the rail-way design like:

– Fundamental Code for Design on Railway Bridge and Culvert (TB10002.1-2005).
– Code for Design of Steel Structure of Railway Bridge (TB10002.2-2005).
– Code for Design on Reinforced and Pre-stressed Concrete Structure of Railway Bridge and Culvert (TB10002.3-2005).
– Code for Design on Concrete and Block Masonry Structure of Railway Bridge and Culvert (TB10002.4-2005).
– Code for Design on Subsoil and Foundation of Railway Bridge and Culvert (TB10002.5-2005).
– Standard for Constructional Quality Acceptance of Railway Bridge and Culvert Engineering
(TB10415-2003).

2. Research Significance
This paper is to make a comparison between two or more codes in different countries to show the differences and similarities and advantages and disadvantages also for checking the design by the analysis and find the suitability of using the structure according to the design.
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Eco Friendly And Sustainable Transportation

Abstract
In this paper two aspects of eco-friendly transportation has been discussed. Transportation is a huge consumer of energy and resources and also a major source of environment pollution (basically air pollution). People tend to use motorized vehicle even for the short distances because of inconvenience and unsafe conditions for bicycling. This leads excessive use of fuel. Limiting the motorized transportation to a defined boundary is required to control the fuel usage and also to reduce site air and noise pollution. Green vehicles are very much energy efficient, pollution free and convenient mode for short distance travelling. But because of lack of facilities their use is not preferred. Eco-friendly transportation promotes use of such efficient vehicles by adequate provisions. Eco-friendly transportation is beneficial for the users as it keeps environment free of pollution and posses healthy living conditions. The use of green vehicle is one part of eco-friendly transportation, the other and most important aspect of sustainable transportation is the use of the waste materials such as fly ash, steel industry slag, paper industry waste in the construction of pavements, embankments of roads and rails etc. which are dangerous as far as the environmental pollution is concerned.

Key words:– Green vehicle, Eco-friendly or sustainable transportation, fly ash, Construction of pavements.
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Effect Of Eccentricity On Analysis and Design Of Isolated Footings

PAPER ON EFFECT OF ECCENTRICITY ON ANALYSIS & DESIGN OF ISOLATED FOOTINGS
(A CASE STUDY OF Jammu and Kashmir)

Note – Right click on images and click view image to see actual size of image

ABSTRACT
Footings are often subjected to moments from columns in addition to the axial loads. The presence of certain amount of eccentricity of loading in the footing induces moment on footing. A careful consideration has to be given to the presence of eccentricity, while performing the analysis and design of such footings, as an increase in eccentricity beyond certain limit renders a considerable area of footing ineffective to resist the stresses due to development of tension. Under these circumstances, the conventional flexural equation becomes inapplicable, thereby imparting more complexity in the analysis.

In this Thesis an attempt has been made to understand the behaviour of footings subjected to Uniaxial and biaxial eccentricity.

Two cases of uniaxial eccentricity are considered, Case I with column placed away from centre of footing, load being concentric with the column and Case II with column at centre of footing and load placed at certain eccentricity. For each case three conditions of eccentricity are considered ie e=0, eL/6. Complete analysis has been performed using Limit State Method for SBC = 40, 50, 65 and 100 KN/Sq m which are prevalent in the region under consideration. For biaxial cases two eccentricity conditions with eL/6 and SBC = 100 KN/Sq m have been analyzed. The analysis of footing subjected to biaxial eccentricity was carried out manually and as per charts and tables prevalent in literature.

A comparative study was conducted for both cases with reference to the design parameters and permissible values. The effect of eccentricity on quantity, cost and various other parameters were studied. The analysis was also carried out using SAP – 2000 Software for both Uniaxial and Biaxial Cases. The results obtained manually and by the use of software have been compared and difference analyzed. A computer program was developed for Analysis and Design of footing for Uniaxial and Biaxial cases in M.S. Excel to reduce the iterative work and to save time.

It was observed that there is a remarkable increase in quantity of concrete and steel when the loads are eccentric, the increasing factor being more in case of column placed away from the centre of footing as compared to the column placed at centre of footing. The results also highlight that the foundations become highly uneconomical if the geotechnical investigation reveals incorrect values of safe bearing capacities.
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Cement And Water Saving With Water Reducers

By
Er. Kaushal Kishore ,
Materials Engineer, Roorkee

In India 0.93 kg of CO2 is emitted in the production of one kg of cement. In the financial year 2009-10 India produces 200 million tonnes of cement. In the production of this cement 186 million tonnes of CO2 was emitted in the atmosphere during financial year of 2009-10.

The availability of water in India per person per year in 1950 was 5177 cu.m. In the year 2009 it is reduces to 1700 cu.m.

If 50 million tonnes cement in making concrete uses water reducers 7500000 tonnes of cement can be saved. 3750000 kl of potable water will be saved and the saving of Rs. 3300 crores per year to construction industry. This amount is worked out after adjusting the cost of water reducers. Less cement used means less cement required to be produce by the cement factories resulting 6975000 tonnes of CO2 will be prevented to be emitted to the atmosphere. These are worked out with an average saving of 15% cement and 15% water.

CO2 emission is word problem, but for India in addition to CO2 it has problems of Air, Water, Soil, Food and Noise pollutions. Less densily populated countries may cope with these problems but for India it is of the top concern. The population figures of 2009 is, India 350 person per sq.km, China 132 person per sq.km and USA only 34 person per sq.km. The figures of 2006 CO¬2 emissions are USA 658.60 tonnes per sq.km, China 611.76 tonnes per sq.km and India 459.35 tonnes per sq.km. Every one should contribute his or her efforts to save the environment from pollution. Those involve in the construction activities can contribute their share by proper design of concrete Mixes. This is best illustrated by the following examples.
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