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Planning of building - Orientation

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 Planning of a building includes various principles such as aspect, prospect, orientation, privacy, circulation, grouping, roominess etc. Today we will talk about the principle of orientation. so, now let's start.   Orientation means arrangement of rooms with respect to the north direction. In a plan of building, we can place the all types of rooms in various way. Some way may be effective or some way may be ineffective or unattractive. Generally, people make the plan themselves for their proposed residential building and in this connection they get quite confused in placement of rooms like kitchen, bathroom, living room, bedrooms, study room, store room etc. So, today I will give you a idea of how to place different types of room to get a pleasant feeling.  According to civil engineering, the plan should be oriented with respect to the north in such a way that kitchen lies towards east and north - east, bedrooms are towards south to southwest and maximum hall windows sh...

Get a plan for your newly proposed building.

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  Hi guys,  Are you looking for a plan for your newly proposed building? Are you facing a problem in designing a plan for your house or office? Have you to construct a building according to a great plan?   If you have these questions, then I am here to solve your problem.  Thank you.

Analysis of perfect frame (Truss)

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  Definition of frame A structure made up of several bars riveted or welded together is known as frame. Types of frame There are two types of frame - Perfect frame and  Imperfect frame Perfect frame - A perfect frame is the which follows the equation n = 2j - 3. where, n = number of members and  j = number of joints In this type of frame, the number of members are just sufficient to keep the frame in equilibrium under an external load. There is no extra member is present in a perfect frame. Imperfect frame - An imperfect frame is one which does not follow the n = 2j - 3 equation. If the number of members in a frame are less than ( 2j - 3 ) then the frame is known as deficient frame. If the number of members in a frame are more than ( 2j -3 ) then the frame is called redundant frame. Assumptions made in analysis of frame The following assumptions are made in finding out the forces in a frame -  The frame is a perfect frame.  The frame carries load at the joints....

PIEV theory in transportation engineering.

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 Today I will induce you with PIEV theory which have great importance in transportation engineering. So, now let me explain. Assume that you are a newbie in cycling. You have just learnt to ride a cycle. You have not much experience and you often get confused when a vehicle or obstacle comes in front of you. Now let you are riding a cycle as you feel comfortable. Suddenly you see a obstacle and hit the brake and stop the cycle. It seems very easy in practical but its principle is quite interesting. It is based on PIEV theory. P - Perception  I - Intellection E - Emotion V - Volition You watched the obstacle and brake the cycle. The time you took to brake the cycle is called braking time. Braking time = perception time + intellection time + emotion time + volition time. Perception time - When you see the obstacle or hear some undesirable sounds, you eyes or ears to send the sensations to the brain through the nervous system and spinal chord. The time taken by your eyes or ears ...

Nominal mix - Definition and grades.

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The concrete proportion of M5 to M25 grade concrete are called Nominal mix.   Nominal mix is generally adopted for small scale constructions. In this type of mix, the mix ratios and concrete constituent proportions are prefixed and specified. Example- For M20 grade of concrete, the quantity of cement, sand aggregate is batched in volume as per the fixed ratio 1:1.5:3. Thank you.

How to identify fake and genuine cement ?

How to identify fake and genuine cement ? The answer of this question should be known to everyone because it is very useful in our practical life. So, now let me explain.   By doing some simple activity we can distinguish between the fake cement and genuine one. You can do these small efforts -  Open the bag and take a look at the cement. If any visible lumps are present and feel oily when it is touched, it is an adulterated or fake cement otherwise not. If you push your hand inside the cement bag and you get cool feeling then it is fine otherwise fake one. Take a pinch of cement and rub it between the fingers. If it give smooth feeling then it is fine. Throw a handful of cement in the bucket having water, if particles float for sometime, it is genuine one. Take a cement sample on a steel plate and heat it on stove. After sometime, if the color of cement changes then it is adulterated otherwise not. Thus, you can differentiate the fake and genuine cement by going through some ...

Planning of building - Roominess and its principle.

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Roominess is an important term used in planning of building.    Roominess is a psychological feeling about bigness or smallness of space or a room. This is a very interesting phenomena. It is common observation that a square room appears smaller than a rectangular room of exactly the same area.   It seems mysterious but there is a reason for it. A rectangular room has greater perimeter than a square room of the same area. When we assess the largeness of the rooms, our eyes take a few microseconds more to observe the rectangular room. Thus our subconscious judges the rectangular room as bigger.   In general, the length and breadth ratio of 1.5:1 to 2:1 is good for roominess. If length is increased beyond this, a bad effect sets and room appear even longer than it actually is. This effect is called tunnel effect.   The height of a room also plays an important part in roominess. The height should be such that we have to look up sufficiently to see the junction of w...

Soil - Formation and its importance

Formation of soil Due to collision of internal moving earth's plates, the magma comes out on the upper surface of the earth. After a long time, the magma gets cold and gain a solid state. This solid state is called rock.     After suffering from different weathering conditions like rain, wind , high temperature, sun etc. rocks are deteriorated in small or micro particles by the time. These particles form soil.     Formation of soil is a very slow process. It takes year in crores. Importance of soil in civil engineering structure Soil is the first requirement to start any type of civil engineering project. All structures are built on earth surface i.e. soil. Soil provide a platform on which all works take place. Soil covers the foundation of any structure. Soil forms the brick by going through some special heat arrangement. Thank you.

Wall finishes - Painting, its necessity, process etc.

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Painting  -    Paints are the fluid materials which are used as a coating on a wall or other surface to finish it. When we apply paints as a coating for finishing the wall, the process is called Painting. Necessity of painting -  It protects the surface from weathering effects of the atmosphere. It prevents decay of wood and corrosion in metal. It gives good appearance to the surface. Characteristics of good paint - It should have good consistency with good covering materials in form of powder. It should not be toxic and should not harm the user. It should be economical. It should remain properly to the surface. It should give pleasant appearance to the surface. It should be fire and moisture resistance. It should be retained on the surface for long time. Ingredients of an oil paint - Base - It is the solid component of the paint exists in form of powder. It forms the bulk of a paint. Various bases are white lead, red lead, zinc oxides, iron oxide, titanium white, Al...

Wall finishes - Pointing, its necessity and method.

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Pointing  :-     Pointing is a process of finishing the mortar joints in the exposed masonry with suitable cement or lime mortar. It can be done just after the completion of the wall or later. Necessity of pointing  :- To protect the joints from weather condition. To improve the appearance of the building structure. It is comparatively a cheaper method of protecting the joints. For pointing generally two types of mortar is used. lime mortar  (1 : 2) cement mortar (1: 3) Method of pointing  :- All the mortar joints in the masonry are racked out to depth of 10 - 15 mm with the help of pointing tools. Dust and loose mortar are thoroughly cleaned. The joints and the surface are washed with clean water and kept wet for sometime. The joints are filled up with mortar by using small trowel, by pressing it into the joints to form a close contact with the old mortar joints. Excess mortar is scrapped away. The finished work is cured for 3-4 days in case of lime mortar...

Impact test on aggregate (IS:5640-1970)

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  Objective - To determine the impact value of given road aggregate. Apparatus & materials required -  Impact testing machine. A cylindrical metal having internal diameter 75 mm and depth 50 mm. Tamping rod of 10 mm diameter and 230 mm long. IS sieve of sizes 12.5 mm, 10 mm and 2.36 mm. Balance Thermostatic oven Aggregate sample Theory - The aggregate impact value indicates a relative measure of the resistance of an aggregate to impact. The aggregate impact value is expressed as the percentages of fines formed in terms of the total weight of the sample.     Due to traffic loads, the road aggregates are subjected to impact and and there is possibility of aggregates breaking into smaller pieces. The road aggregate should be tough enough to resist fracture under impact. A test designed to evaluate the toughness of aggregate is called aggregate impact test.                                ...

Rebound Hammer Test as per IS 13311(part-2)-1992.

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Rebound hammer test is a non-destructive concrete test which takes place to give the quality of concrete without damaging the concrete structure. It measures the elastic rebound of concrete and is used for determination of concrete strength. This test is conducted by Schmitt rebound hammer which carries a driving spring, a release button, casing, a plunger, a spring controlled hammer, tabular housing, mass and a scale. These units are arranged within a body such that when plunger hit the concrete surface, the mass rebounds from the plunger and the distance travelled by the mass gives the rebound number. This test can be conducted horizontally, vertically, upwards or downwards or at any intermediate angle. Procedure for rebound hammer test - Before starting the procedure, calibration of the hammer is required. The surface of concrete is cleaned . The hammer is held at right angle to concrete surface structure. After holding hammer in position, the plunger is made to hit the concrete sur...

Concrete Mix Design as per IS 10262:1982.

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 Concrete mix design deals with following steps. Step 1 - The target mean strength is calculated.         ft = fck + K x S where, ft = Target mean strength             fck = The strength of concrete mix which we want to design           K = 1.65            S = standard deviation Step 2 - The value of w/c ratio corresponding to target mean strength is taken from the graph. Step 3 - Maximum water content is taken from IS 10262:1982 corresponding to nominal size of coarse aggregate and slump 25 to 50 mm. Value of water content is increased by 3% for each additional 25 mm slump and reduced by 5-10% for plasticizer and 20% for superplasticizer. Requirement of water reduces with increase in normal size of aggregate. Step 4 - The quantity of cement is calculated.     wt. of cement = (wt. of water) / (w/c ratio) This value should not be less than minimum cement required cor...

Lug angle and tension splice - Introduction

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  Lug angle - Lug angle is an angle section of short length which connects the outstanding legs of angle section or member to the gusset plate.  It reduces the length of connection to the gusset plate and also reduces the shear lag effect.   When the lug angle is used, the unconnected length of main angle acts like a connected leg and hence entire cross-section area start resisting the tension. Thus, shear lag effect reduces and efficiency of the tension member increases.   Lug angle provides extra gauge line to accommodate the numbers of bolts.   Tension splice - Tension splice are the cover plates used on both sides of butt jointed members. A tension member is spliced when the length of section available is less than that of tension member required. when the members of different thickness are spliced, packing is required to fill the gap. The area of splices should be slightly more than that the member joined. It is also used when the size of the memb...

Multiple Choice Questions from Geometric Design of Highway.

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Go through these questions and test yourself. 1. The portion of the road surface which is used by the vehicular traffic is known as Carriage Way Shoulder Expressway All of these Answer - Carriage Way 2. Geometric design of highway deals with Cross section elements Sight distance consideration Horizontal alignment details All of the above Answer - All of the above 3. Which of the following term doesn't come under cross section elements ? Camber Kerbs Carriage Way Right of way Answer - Right of way 4. As per IRC recommendations, the coefficient of longitudinal friction varies from 0.35 - 0.38 0.30 - 0.35 0.35 - 0.4 0.4 - 0.45 Answer - 0.35 - 0.4 5. As per IRC, coefficient of lateral friction should be  0.12 0.15 0.18 0.20 Answer - 0.15 6. Longitudinal friction is useful in  Sight distance calculation Horizontal curve design Width of pavement calculation (a) and (b) both Answer - Sight distance calculation 7. An unevenness index value less than ________ is considered as good...

Creep of concrete - definition and factors affecting the concrete.

Creep is defined as gradual increase in strain without increase in stress with time. It is also known as plastic flow or time yield.   Creep may be due to viscous flow of cement-water paste or flow of water out of the cement resulting in the closure of internal voids. It also takes place due to readjustment of molecules. Factors affecting creep of concrete :- Influence of aggregate - aggregate shows a restraining effect on creep. stronger the aggregate, more is the restraining effect and less is the creep. Light-weight aggregate shows higher creep than normal weight aggregate due to lower modulus of elasticity.       2. Influence of mix design -  Creep increases with increase in w/c ratio. Creep is inversely proportional to the strength of concrete. Poor paste shows higher creep.            3. Age of concrete - Since quality of concrete improves with time. So older concrete is creepless whereas young concrete shows creep. After...

To find out the silt content in sand

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Objective - To find out the silt content in sand. Apparatus required -     A measuring cylinder (250 ml) Water Sand Theory - A good quality construction sand should has particles of 150µ to 4.75 mm. Particles smaller than this are classified as silt. The presence of excess quantity of silt in sand reduces the bonding capacity of raw materials and affects the strength and durability of work.  It is recommended to conduct silt content test  for every 20 ㎥ of sand. Procedure -  A 50 ml solution of 1% salt and water is prepared in the measuring cylinder. The sample of sand is then added to the cylinder until the level reaches 100 ml. 50 ml of the solution of 1% salt and water is again added to the measuring cylinder. The open end of the measuring cylinder is closed and then it is shaken well.  After 3-4 hours, it is noticed that a layer of silt is settle over the sand. Now the volume of silt layer settle over the sand is taken as v1. The volume of settle s...

Abrahm's law of water-cement ratio - Mathematical relation and graph

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 Abrahm's law expresses the relation between compressive strength of concrete mix and the  water-cement ratio which is taken in designing concrete mix.   This law states that the compressive strength of concrete mix is inversely related to its water/cement ratio.     If water/cement ratio (w/c ratio) increases, the strength of concrete decreases. He presented his classic law as :- S = A/B* where, S = compressive strength of concrete mix             * = water/cement ratio             A and B are constants.  The graph showing the relation between the strength and w/c ratio of the concrete mix is approximately hyperbolic shape.     The graph says, lower w/c ratio is taken when the concrete is vibrated for compaction and higher w/c ratio is required for hand compaction of concrete.   If we draw a line graph to show the relation between strength and c/w ratio , it shows approximately a li...

Darcy's law of permeability - explanation and formula

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 Permeability is the property of a porous material which permits the seepage of water through its interconnecting voids. The flow of water through soil may either be a laminar flow or a turbulent flow. Darcy's law states that, " For laminar flow conditions in a saturated soil, the rate of flow or the discharge per unit time is proportional to the hydraulic gradient." V ∝ i V  = ki where k is co-efficient of permeability. since, q =   AV = kiA q = discharge per unit time A = total cross-sectional area of soil mass i = hydraulic gradient V = Discharge velocity      If a soil mass of length L and cross -sectional area A is subjected to differential head of water ( ∆h), the hydraulic gradient i will be ∆h/L. And, q = k(∆h/L)A. When hydraulic gradient is unity, k = V. Thus, co-efficient of permeability is the average velocity of flow that will occur through the total cross-sectional area of soil under unit hydraulic gradient.  Thank you. Gracious !   ...

Difference between butt joint and lap joint

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  LAP JOINT - In this joint, two members are overlapped and connected together. The load in lap joint has eccentricity because centre of gravity of load in both members are not in same line. Thus, a couple is formed which causes undesirable bending in the connection and the rivets may fail in tension. Also due to the eccentricity, the stresses are distributed unevenly across the contact area between the rivets and members to be connected.   BUTT JOINT - In butt joint, both members are placed end to end and additional plate/plates (cover plate) is provided on either one side or both sides and connected to the main plates. When one cover is provided, it is called single cover riveted butt joint and when double cover is provided,it is called double cover riveted butt joint.   It was the difference between lap and butt joint. Now, we will know superiority of butt joint. Butt joint is superior than lap joint because 1. In the case of a double cover butt joint, eccentricity of ...

Difference between short, intermediate and long column

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 We  can visualize the all three columns on three basis - Their length Slenderness ratio Mode of failure. Short column :- Length ≤ 8 times of its least lateral dimension. Slenderness ratio = 0 - 32 Failed due to crushing. Intermediate column :- Length = 8 - 30 times of its least lateral dimension. Slenderness ratio = 32–120. Failed due to crushing and buckling combinedly. Long column :- Length > 30 times of its least lateral dimension. Slenderness ratio > 120 Failed due to buckling.