Punjab State Board of Technical Education and Industrial Training 2010 Diploma Civil Engineering Building Construction - Question Paper

Surveying

1 ) In metric chain, one meter length is divided into 5 links . 2 ) Generally one chain is accompanied by ten arrows. 3 ) Offset rod is used for taking Short offset. 4 ) Error due to wrong ranging is cumulative. 5 ) In case of a building Chaining, vision are obstructed. 6 ) The least count of a prismatic compass is 30 . 7 ) The systems of bearing are whole circle and reduced . 8 ) Plane table surveying is less costly than theodolite surveying.

Chain Surveying:- It is the method of surveying in which the area is divided into net work of triangles and the sides of the various triangles are measured directly in the field with chain or tape and no angular measurements are taken. It is simplest kind of surveying and is most suitable when the area to be surveyed is small in extent and is fairly level and open with simple details. It is unsuitable for large area.

Principle of C. S. :- The principle of chain surveying is to divide the area to be surveyed into a network of connected triangles as a triangle is the only simple figure that can be plotted from the lengths of its sides measured in the field. Since triangulation forms the principle of chain surveying, the chain survey is also sometimes called as chain triangulation. > If the area to be surveyed is triangular in shape and if the lengths and sequence of its three sides are recorded, the plan of the area can be easily drawn.

A.M.

Moment:- The turning effect produced by the force on the body is called moment. Principle of Moments:- The algebraic sum of the moments in equilibrium is equal to zero, is known as principle of moments. Lever:- A lever may be defined as a rigid bar, straight, bent or curved which is free to rotate about a fixed point in it. This fixed point in the lever is called fulcrum of the lever and is denoted by the symbol O or . Couple:- Two equal and unlike parallel forces acting on a body, whose lines of action are not along the same straight line. Moment of couple:- When a couple acts on a body, the tendency of the couple is to case rotation of the body. This tendency is measured by the product P x X and is called the moment of the couple.

Machine:- A machine may be defined as a device which receives energy in some available form and then by using that energy it delivers useful work. Simple Machines:- A machine having only one point at which effort can be applied and one point for load is known as simple machine. Resistance:- The mass or load to be lifted or friction to be overcome by a machine is called resistance. It is denoted by W. Effort:- The force applied to a machine to lift a load or to overcome resistance is known as effort. It is denoted by P. Input to a machine:- The work done on a machine by the effort is called its input. It is measured by the product of effort (P) and the distance(y) through which it has moved in the direction of effort. Then, Input = P x Y. Output of a machine:- The actual work done by the machine is known as its output. It is measured by the product of the resistance overcome (W) and the distance () through which this resistance is overcome. Then, Output = W x Mechanical Advantage:- It is defined as the ratio of the resistance overcome to the effort applied to the machine. If W is the resistance overcome when an effort P is applied, Than M.A. = W/P. Its value is always greater than one. Velocity Ratio:- The velocity ratio of a machine is the ratio of the distance moved by the effort in a certain time to the distance moved by the resistance in the same time. Then, V.R. = . Efficiency of a machine:- The ratio of output to input is called the efficiency of the machine. It is generally expressed as a percentage and is denoted by Greek letter eta, Efficiency = output/input x 100. Ideal machine:- A machine completely free from frictional resistance is called an ideal machines. The efficiency of such a machine is 100% i.e. output = input.

Cement:- The product obtained by burning and crushing to powder either stone containing 20 to 40 % clay and remaining carbonate of lime or an intimate mixture of well proportioned calcareous and argillaceous materials is called cement.

Wet process;- This method of manufacturing cement is adopted when the raw material are soft. This process is mostly used now a days as the quality of cement.

(a)       Collection of raw materials.

(b)       Mixing

Collection of raw materials:- The raw materials calcareous as well as argillaceous materials are quarried from the nearest quarry. These materials are then transported and collected at the factory site be means of any suitable transport facility available in that area.

Mixing:- The quarried limestone is first crushed upto one cm size pebbles by means of a hammer crusher. These are then stored in large tanks by means of elevators.

After this the proportioned materials are fed into the wet grinding mill along with 20 to 40% of water. In this mill these materials are further finely ground to form an intimate mix with water which is known as raw slurry.

B.C.

Frame:- The assembly of horizontal and vertical members placed along the top, bottom and sides of an opening so as to form an enclosure for a door or a window shutter is called a frame.

Head:- The top horizontal member of the frame is called head.

Reveal:- The narrow cross surface of wall external jambs of a door or window opening projecting on the outside of the frame is called reveal.

Floor finish:- The top surface of the floor is called floor finish or wearing surface.

Topping:- The top most layer of the floor provided either over the base course or over the under layer is called topping.

Base-course:- The prepared surface on which the topping or under layer is laid is called base and the layer of material provided is called base-course.

Effects of dampness:-

1 Softening and crumbling of plaster. 2 Damaged floor tiles as they loose adhesion with the floor bases.

3 Deterioration of electric installations. 4 Decaying of timber. 5 Corrosion of matal.