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Traverse and type of traverse

  A Traverse is a series of a connected lines whose length and direction are measure in the field. The fieldwork in a theodolite traverse consists of the following: (i) reconnaissance, (ii) selection and marking of stations, (ii) measurement of traverse lines, (iv) angular measurements and (v) picking up the details. Types of Traverse In  Open Traverse , the endpoint is not the same as the starting point, the traverse starts at a point P and goes along a direction that does not return to the point P. Fig 1: Open Traverse In  Closed Traverse , the traverse ends at the starting point forming a closed loop. Fig 2: Closed Traverse In the figure above, the stations P, Q, R, and S of a traverse are called traverse stations, and the lines PQ, QR, and RS are called traverse lines. The direction of the traverse has shown with an arrow. General Procedure of Theodolite Traverse 1. Set up the instrument over the station P. Centre and level it accurately. Keep the telescope in the normal positio

Classification and type of soil water

CLASSIFICATION AND TYPES OF SOIL WATER When water is spread over the soil either by rainfall or by irrigation, the water is absorbed by the pores of the soil is termed soil moisture or soil water. The various forms of soil water are (a) Gravitational Water, C) Hygroscopic Water and (c) Hygroscopic Water.                           Fig: Soil Water (a) Gravitational Water When water is added to the soil during rains or irrigation, the water content of the soil goes on increasing until a saturation point is reached as shown in the figure above. At this point, the soil pores are filled with water completely and no more water is absorbed by the soil. The surface water then starts flowing downwards due to the influence of gravity. The portion of water which moves downward is known as gravitational water. This water is not useful for the plants as it flows out rapidly and cannot be absorbed by the root zone. (b) Capillary Water The portion of the water retained by the soil after gravitational

Inundation irrigation and Perennial irrigation

The following point is the comparison between Inundation irrigation and Perennial irrigation 1. In Inundation the irrigation water is available in rainy season only whereas In Perennial the irrigation water is available throughout the year. 2. In Inundation irrigation no hydraulic the structure is necessary whereas In Perennial irrigation Hydraulic structures are necessary, (such as diversion head, headworks, cross-drainage works, etc.). 3. In Inundation irrigation the canal water contains plenty of silt which makes the land fertile whereas In Perennial irrigation the canal water contain practically no silt and hence chemical manure is essential. 4. In Inundation irrigation  large the area cannot be included under this system whereas In Perennial irrigation large area can be included under this system. 5. In Inundation irrigation  the silting of the canal bed is a major problem whereas In Perennial irrigation negligible silting takes place in the canal bed. 6. Initial cost is low in In

Water Budget Equation numerical

Q. A lake has a surface area of 7 x 10 5  sq m. During  given Month , the mean inflow to the lake was 2.5 m 3 /s. The increasing in stored lake volume was absorb to be 6.5 x 10 5  m 3 .  Precipitation during the same month was 250mm and evaporation was 420mm. For the same month, calculate the outflow from the lake. Solution:  Given data,  Surface area (A) = of 7 x 10 5  sq m Inflow (Q in ) =  2.5 m 3 /s Increasing in Volume =6.5 x 10 5  m 3        (we need to convert in m 3 /s)                                         = (6.5 x 10 5 )/(30 x 24 x 60 x 60) (For a month in second we have = 30days x 24hrs x 60min x 60s)                                          = 0.25 m 3 /s Precipitation (P) = 250mm                         =(250 x 7 x 10 5 ) /(1000 x30 x 24 x 60 x 60)                         =  0.0675 m 3 /s Evaporation (E)= 420mm                         =(420 x 7 x 10 5 ) /(1000 x30 x 24 x 60 x 60)                         =  0.1134 m 3 /s Outflow (Q out ) =? We know that, Inflow – Outflow =

Three phase system numerical

Three phase diagram Example1: The void ratio and specific gravity of a sample of clay are 0.74 and 2.73 respectively. If the voids are 93% saturated, find the bulk density, the dry density and the water content. What would be the water content for full saturation, for the same void ratio? Solution:       Given Data,                                e= 0.74,       G = 2.73,             S=93% We know that,                                 Se = w .G                     0.93 x 0.74 = w x 2.73                                    W = 0.252                   Bulk density =(G+Se)/(1+e)                                        = (2.7 + 0.92 x 0.73)/( 1 +0.73)                                     =1.964 x 9.81                                    =19.267KN/m 3               Dry density = Bulk density/1+ w                                  = 19.13/(1 + .248)                                    = 15.389 KN/m 3 Water content for full saturation at sane void ratio                

Landslide and different types of landslide

Landslide and its types The term "landslide" is a wide variety of processes that result in the outward movement and downward movement of slope-forming materials including rock, soil, artificial fill, or a combination of these. The materials may move by falling, toppling, sliding, spreading, or flowing. 1. Slides: A slide is a type of Landslide which is characterized by failure of material at depth and then moved by sliding along a rupture or slip surface. If sliding is on a predominantly planar slip surface then the slide is called a translational slide. If movement is on a curved slip surface then the slide is called a rotational slide. A lot of rotational slides end up as mudflow leaving a gaping hole in the ground where the slide began. Debris from the slide is strewn down a torrent track along which the mudflow travelled to the base of the slope or where the flow path widens and dissipates. A rotational slide with one or more curved slip surfaces where the movement of mat

Seismic wave and types of seismic wave

Seismic wave and types of seismic wave  Seismic waves  are waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. When an earthquake occurs, the shockwaves of released energy that shake the Earth and temporarily turn soft deposits, such as clay, into jelly (liquefaction) are called seismic waves, from the Greek ‘seismos’ meaning ‘earthquake’. Seismic waves are usually generated by movements of the Earth’s tectonic plates but may also be caused by explosions, volcanoes, and landslides. Seismologists use seismographs to record the amount of time it takes seismic waves to travel through different layers of the Earth. As the waves travel through different densities and stiffness, the waves can be refracted and reflected. Because of the different behaviour of waves in different materials, seismologists can deduce the type of material the waves are travelling through. The resu

Type of an earthquake꘡Tectonic Earthquake

Type of an Earthquakes 1. Tectonic Earthquake The earth's crust is made up of unevenly shaped slabs of rocks called tectonic plates. The energy stored here causes the tectonic plates to move towards away or push against each other. With time the stored energy and the movement of the tectonic plates build up the enormous pressure within the region between two plates. That intense pressure becomes the cause of the fault line and plates move over against or apart from each other. From the focus, waves of energy travel towards the surface thus shaking the surface within. From the epicenter of an earthquake, the energy waves travelled in a different direction on the earth's surface causes vigorous movement on the surface of the earth which is known as an earthquake. A  tectonic  earthquake is one that occurs when the earth's crust breaks due to geological forces on rocks and adjoining plates that cause physical and chemical changes. 2. Volcanic earthquake A  volcanic  earthquake

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Least count of surveying instruments

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What does M20 means? type of concrete mix and purposes

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How to calculate Weight of Steel Bar Per meter length

Weight of Steel Bar Per meter length    We know that,         Density of Steel = 78.5 quintal/ m 3            Also, 1quintal = 100 kg        Density of Steel = 78.5 x 100                                    = 7850 kg /  m 3 For 8mm diameter bar (0.008m)     Area = Π/4 x d 2         (d= diameter of bar)                       = Π/4 x 0.008 2           = 5.026 x 10 -5  m 2 Weight of 8mm diameter per meter length = 7850 x 5.026 x 10 -5                                                                     = 0.39 kg / meter For 10mm diameter bar (0.01m) Area = Π/4 x d 2          = Π/4 x 0.01 2          = 7.854 x 10 -5  m 2 Weight of 10mm diameter per meter length = 7850 x 7.854 x 10 -5                                                                      = 0.62 kg / meter For 12mm diameter bar (0.012m)   Area = Π/4 x d 2          = Π/4 x 0.012 2          = 1.131 x 10 -4  m 2 Weight of 12mm diameter per meter length = 7850 x 1.131 x 10 -4