Indian road Congress

The Indian Roads Congress ( IRC ) was established in 1934 with the following objectives : 

• To promote and encourage the science and practice of road building and maintenance. 
• To provide a forum for expression of collective opinion of its members on matters affecting roads .
• To promote the use of standard specifications and practices .
• To advise regarding education , experiment and research connected with road.
• To hold periodic meetings to discuss technical questions regarding road 
• To suggest legislation for the development , improvement And protection of roads 
• To suggest improved method of administration , planning, design, operation, use and maintenance of roads.
• To establish, furnish and maintain libraries and museums for furthering the science of road making 

5 Different Types of Traditional Water Harvesting System in India

1. Rajasthan-Based Paar:

Paar was a harvesting practice used in the desert areas of Rajasthan. This involved collecting rainwater from the catchment to let it percolate into the soil. The water in the soil was then accessed by masonry construction of dugs (kuis) in the storage area. The kuis are about 5 m to 12 m deep.

2. Talaab:

These have been popular since the days of the kings. Talaabs are reservoirs—natural (as in Bundelkhand) or man-made (as in Udaipur). These reservoirs were used to meet irrigation and drinking water requirements. These constructions lasted only as long as the monsoon. Post-monsoon, the beds of these water bodies were cultivated with rice.

3. Saza kuva:

These wells were initiated on a partnership basis. With multiple users, these saza kuvas were primarily used for irrigation. A group of farmers usually had one made amongst themselves.

4. Johad:

ADVERTISEMENTS:These are earthen check dams that were meant to collect rainwater. Because of their earthen nature, water percolated easily into these systems. They resulted in tremendous rise of the groundwater levels.

5. Pat:

The pats of the Jhabua district of Madhya Pradesh are irrigation panels. These irrigation panels are fed using water that is diverted from fast moving hill streams.

BAR BENDING SCHEDULE FOR A SLAB

Bar Bending Schedule
Just like any other schedules, bar bending schedule is most important part of any project.
It helps in doing reconciliation of steel and controlling the wastage at site.
If bar bending schedule (BBS) is not prepared at site, then contractor and its workmen tend to cut and and bend bars without quantifying it and leads to more wastage due to over doing it.


I have created a Bar bending Schedule format in excel sheet, which can be used for followings;
Taking approval from Client or Engineer In-charge - Its a Certificate which allow workmen to do work accordingly.
Ordering the required reinforcement steel Quantity.
Issuing Steel bars to contractor as per BBS and avoiding overdoing and wastage.
Reconciliation of done work and identifying the issues in cutting and bending of steel.
It does a great help to fitter to do cutting and bending as all dimensions and cutting length already provided to them in BBS.
It increases productivity of reinforcement workmen and hence reduce the delays in construction activities.
enclosed herewith a sample of bar-bending schedule for the slab

FLOW NET

Before studying a flow net, the following terms need be clearly understood.

1. Flow line - the line followed by percolating water through a saturated soil mass under laminar flow conditions, is called flow line .
2. Equipotential line - the line joining the points of equal hydraulic potentials , is called an equipotential line.
3. Flow net - the flow net work formed by a system of flow lines and equipotential lines . Is called flow net . A flow net is a pictorial representation of the pattern of flow and the dissipation of hydraulic head causing the flow in soil.
4. Flow channel - The portion of a flow net bounded by two adjacent flow lines, is called flow channel.
5. Field - The section of a flow channel located between two adjacent equipotential lines, is called a field 

FUNDAMENTAL CHARACTERISTICS OF A FLOW NET 

• Flow lines and equipotential lines in a flow net intersect at right angles 
• All fields formed by equipotential lines and flow lines are approximate squares. 
• Same quantity of flow occurs through each flow channel 
• Same potential drop occurs between any two successive equipotential lines 
• The smaller the dimension of a field , greater is the hydraulic gradient and also velocity of flow .
• In homogeneous soils, the shape of curves is either clliptical or parabolic. 

What it is Hydrogen?

The branch of physical geography which deals with the origin, distribution, and properties of water of the earth surface is called hydrology.

Engineering hydrology deals with the field of hydrology which is mainly concerned with the wind and operation of engineering projects for the control and use of water . Indeed , the engineer makes use of hydrology as agriculturists , foresters, etc . do

The Hydrological cycle

Water goes on changing from one state to another in a cyclic order . This cycle is visualised at beginning with the evaporation of water from the oceans and lakes. The resulting vapoura are transported by the wind and under proper conditions, these vapours get condensed to form clouds which contribute to the precipitation . The precipitation which falls upon the land is disposed of in several ways as discussed below:

(1) the greater part is temporarily retained in the soil on which it falls and is ultimately returned to the atmosphere either by evaporation or by transpiration by the plants.

(2) A partion of water finds its way over and through the surface soil to stream channels 

(3) A partion of the water penetrates farther into the ground and becomes a parts of the earth's ground water supply.

Uses of hydrology

A study of hydrology ise useful for the following

• For proper design and operation of hydraulic structures 
• For ascertaining flood flows expected at a spillway , or at a highway culvert or in a city drainage system 
• For ascertaining reservoir capacity to ensure adequate water for irrigation or municipal water supply during draughts 
• For ascertaining the effect of reservoirs , levees and other control works in flood flow in a stream

Capacity of a highway

Before we discuss the capacity of a road pavement , the following terms may be clearly understood

1. Traffic valume - the number of vehicles moaving in a specified direction on a roadway that pass a given point during a specified unit of time , is called traffic volume 
2. Traffic density - the number of vehicles occupying a unit length of a roadway at a given instant, is called traffic density . It usually expressed as vehicles per kilometre 
3. Traffic capacity - the maximum number of vehicles in a roadway that can pass a given point in unit time, is called traffic valume 
4. Basic capacity - the maximum of passengers cars that can pass a given point on a roadway during one hour under the most ideal road and traffic conditions , is called basic capacity . It is something called theoretical capacity 
5. Practical capacity - the maximum no of vehicles that can pass a given point on a roadway during one hour without imposing any restriction to the driver's freedom for driving the vehicles, under prevailing roadway and traffic conditions , is called practical capacity . It is some times called design capacity.

Masonry Dams

The structures that are constructed across drainages ( natural or artificial ) to retain water to the required height , are known as dams. The dams which are wholly constructed with stones , are called masonry dames
The following forces generally act on a dam section
1- weight of masonry acting downward
2- pressure of water acting horizontal
To avoid tension in masonry , it is ensured that the resultant of the forces on the dam section , lies within the middle third of the section
While analysing dam section , one should always consider a unit length of the dam .
Now consider the trapezoidal dam section of unit length
Let w= density of water retained
        h= height of water retained
        W = total weight of the masonry acting at its C-G
Water pressure P= 1/2 wh2 acting at h/3 form the base

The resultant R of the force P and W intersect the base at E . To locate E, take the moments of P and W about E. The resultant R may be considered to be equivalent to horizontal through P and vertical force W . The horizontal force does not affect the stresses at the base. The stresses which are developed at the base are, therefore, only due to load W and acts with an eccentricity ,

The maximum stress at the base is at the outer edge away from the water face and minimum stress will be at the edge near the water face

Spacing of rivets according to IS 800-1962

Following limitations are recommended:

1. The distance between center of adjacent rivets should not be less then 2.5 times the diameter of rivet hole
2. The distance between the centres of two adjacent rivets ( including tacking rivets ) joining the members both in conpresscom or in tension should not exceed 32t or 300 mm which ever is less , where t is the thickness of the cover plate 
3. The diadista between the centres of two adjy rivets in the direction of stress shall not exceed 16 t or 200mm whichever is less in tension and 12 t or 200 mm whichever is less in compression

Advantages and Disadvantages of water Bound Macadam

• Advantages - water Bound Macadam is superior in quality because the materials are carefully graded and the resulting mass is almost voidless compacted mass. The interlocking of aggregates particles imparts adequate strength of the materials selected for filling the voids . These ensure non entry of the plastic mstermat of the sub grade into the voids .

• Disadvantages- the stone pieces used in water bound macadam road are keyed together by means of sand and clay and no other cementing material  is used . The bending effects of sand and clay depends upon the pressure of moisture. When the first moving vehicle passes over a W. B. M. Road, the slurry of sand and clay is sucked out by the pneumatic wheel types , the stone pieces get disturbed and finally road surface is disintegrated . Due to this factor , the w.B.M. roads are not suitable for fast moving vehicles with wheel types . These roads are only suitable for slow moving iron wheeled traffic such as tonges , bullocks carts etc, constant use of road by iron wheels , the road matal gets crushed . Considering these important factors , it may be inferred that a w.b.m. road survives only for a short time

A water bound macadam is less costlier as compared to bituminous base course. 

Classification of premix bituminous wearing surfaces

In premix method, the aggregate and the binder are premixed prior to placing and spreading the Mix over the pavement structure.
It mens that every individual aggregate particle receives uniform thickness of the binder film before it is placed . In primix mermet in construction increased stability is achieved because aggregate gradation may be carefully selected to given a dense mass possessing minimum voids.

In the case of grouted macadam , the binder has to reach the full or half aggregate layer by penetrating through the open voids between the aggregate particle. That is why In this construction, more quantity of bitumen is required to fill voids which are deliberately left in the pavement structure to enable the bitumenous binder to penetrate to the lowest layers of stones

The premix bituminous wearing surfaces are classified as under

1. Bitumen bound macadam 
2. Bitumen carpet 
3. Bitumen concrete 
4. Sheet asphalt
5. Mastic asphalt

Method of construction of W.B.M. Road

Water bound macadam roads are constructed through the following stages as detailed below : 

1. Preparation of sub-grade - sub grade is provided by digging up the sub soil and the level of the sub - grade is decided by subtracting the total thickness of the pavement from the finished level of the road pavement . Form the finished level of the road pavement . The sub grade is throughly compacted by rollers weighing 8 tonnes by during rolling must be made up to and brought to the grade as required.  In rocky regions the sub grade are not rolled whearas in region of clay soils, a layer to natural sand moorum or gravel , is provided over sub grade and is duly-packed.
2. Preparation of sub-base - on the well compacted subgrade , spread 10 to 20 cm size boulders or broken stones , or over burnt bricks in layer of 15 cm thickness and total width of the sub base to be kept 60 cm wider then the pavement width , projecting 30 cm on each sides . The sub base should be compacted by a roller to provide an even surface 
3. Preparation of base - on the prepared sub- base or directly on sub grade, as the case may be, the specified materials of the base course is spread and proper grade, thickness and cross sections maintenaned as per design shown on the supplied drawings
4. Preparation of wearing course - this course may be laid in one or two layers according to the total designed thickness and the thickness of each layer should not exceed 10 cm . This component being very important, the following steps may be taken systematically

      (1) check the defective portions of the newly laid                   base course i.e. soling and rectify them

       (2) provided either bricks on end edging or                         earthen kerbs strong enough to prevent the new road material form spreading outward and also to       l retain water used in consolidation of the wearing   ourse .