Rkr engineer

Foundation                       Foundation is the lowest part of the stuctstruewhich is provided below the ground surface and transmit the load of the structure to the ground. Types of Foundation                                       The following are the different types of Foundation 1) spread Foundation 2) Pile Foundation 3) Pier Foundation Spread Foundation are further classified as 1) Wall footing 2) Isolated or column footing 3) Combined footing 4) Cantilever footing 5) Continuous footing 6) Grillage footing 7) Raft or Mat footing 8) Stepped Foundation                                            

Types of rails                             The rails which are used for railway track should be such that every part of the rail can withstand agianst maximum allowable stress . The design cross sectional area of rail should be economically . There are three types of rails are used in the construction of a railway track. 1) Double headed rails 2) Bull headed rails 3) Flat footed rails 1) Double headed rails                                           Double headed rails having rail section head and foot of same dimensions are termed as double headed rails. Double headed rails section were used in the early stages of railway. These are designed with a point of view that when top of head which get wear out during the movement of traffic should be replaced with foot , to reuse it when reneeded because head and foot have indentical dimensions thus life of rail can be increased by inverting the rail and reuse it. 2) Bull headed rails                                       The ra

Surveying                     Surveying is the of determining the relative position of points on, above or beneath surface of earth by means of direct sand indirect measurements of distance, direction and elevation. Various methods of measuring the distance directly are 1) Placing                     The distance is measured by counting the number of places and then multiply by the distance of one pace. This is rough method. 2) Passometer                             Passometer is an instrument shaped like a watch and carried in pocket or attached to one leg. The instrument registers the number of places. 3) Pedometer                           This is the modified version of Passometer whereby adjusting for the length of pace, direct reading of the distance can be registered. 4) Odometer and speedometer                                                           odometer registers the number of revolutions of a wheel. If a wheel is rolled along the line for which distance i

Cement                 The product obtained by burning and crushing to powder either stone containing 1/5 the or 2/5 th clay and remaining carbonate of lime or an intimate mixture of well proportioned calcareous and argillaceous material is called cement. Calcareous material are lime stone , mark, chalk or shells etc. Argillaceous material are silica , clay, oxide of iron etc. Commonly used cement for normal construction work is ordinary Portland cement composition of Portland cement. a) calcium oxide                        = 60 to 65% b) silica                                        =  20 to 25%  c) aluminium oxide                  =  4 to 8% d) ferrous oxide                         = 2 to 4%        e) magnesium oxide                 = 1 to 3% f) Sulphur trioxide                    = .5 to 3% Cementation value          = 2.8 A +1.1 B + .7C /1.0 D + 1.4 E A = percentage of silica content by weight B = percentage of alumina content by weight C = percentage of ferric oxide b

Stone           Stone have been used for building purpose from the immemorial . Building stones are obtained from rocks occuring in nature. Geologically the rocks are divided into three parts. 1) Igneous rocks 2) Sedimentary rocks 3) metamorphic rocks 1) igneous rocks                                 Which are of volcanic origin they represent a crystalline glassy or fussed structure. These rocks are hard dense, tough impervious, strong and durable. Stones have obtained from these rocks are granite , basalt trap. 2) sedimentary rocks                                         Which are formed from sediment through the agency of water , wind or glacier. Usually these rocks have budding structure arranged in layers. Stones obtained are known as sand stone , shale, limestone and laterite. 3) Metamorphic rocks                                            Which are formed in either of the above two processes but subsequently changed or matamorphised in colour structure and texture due

Testing of cement                                  Testing of cement can be broadly into two categories. 1) Field testing 2) Laboratory testing A) Field testing                               For ordinary work of less public importance one can perform field testing of cement to ensure about the quality of cement. Following observations and tests can be performed in the field to roughly know about its quality at the time of usage. 1) Take a look at the cement, there should not be any visible lumps. 2) The colour of the cement should normally be greenish grey. 3) Put your hand into the cement bag , it should give you a cool feeling. 4) Take a pinch of cement between your fingers, it should give a smooth feeling. 5) It should not feel oily when touched. 6) Take a handful of cement and throw it on bucket full of water , the particles should float for sometime before they sink. 7) Heat the cement on a hot plate for about 20 minutes. It should not change its Colour. B) Labora

Types of cement                              These cement are classified as Portland cement and non- Portland cements. The difference between them is mainly based on the methods of manufacture. The Portland and non- Portland cements generally used as listed below. 1 ordinary portPort cement ( opc) a 33 grade ( IS :269-1989 ) b 43 grade ( IS :8112-1989 ) c 53 grade (IS :12269-1987 ) 2 Rapid hardening cement 3 Low heat Portland cement 4 Sulphate resisting cement 5 Blast furnace slag cement  6 Masonry cement 7 White and coloured Portland cement 8 Air entraining cement 9  Portland pozzolana  cement 10 High alumina cement 11 Oil well cement 12 Quick setting cement 13 Hydrophobic cement 14 Expansive cement

Concrete                   Concrete is a mixture of cement , sand , water and gravel in same proportion. Concrete is used for building construction and other many structure of civil engineering. Ingredients of concrete                                           The material used to make concrete are called it's ingredients. The key to produce a strong, durable and uniform concrete lies in careful control of its basic ingredients. Ingredients of concrete can be classified into two groups, active and inactive. The active group consists of cement and water , whereas inactive group comprises of fine and coarse aggregate. Types of concrete                                  1 cement concrete 2 lime concrete 3 Reinforced cement concrete 4 Prestressed cement concrete 1 Cement concrete                               Cement concrete is a mixture of cement ,sand ,water and coarse aggregate. 2 Lime concrete                               Lime concrete is a mixture of hydraulic l

Rcc          Rcc is a reinforced cement concrete. Rcc is a composite material which is made up concrete and steel reinforcement. Steel bars are placed in the tension zone of the structure and take up tensile stresses. Rcc unit weight is 2500 kg/m3 Rcc full form                          Reinforced cement concrete Reinforcing material                                         The material which develops a good bond with concrete in order to increase its strength is referred as reinforcing material. The reinforcing material should have the following characteristics 1 It should be able to develop a good bond with concrete. 2 It should have coefficient of thermal expansion nearly same as that of concrete so that the thermal stresses do not develop. 3  It should have high tensile strength. 4 It should have easy to cut , bend and weld.