Water Leak Detection Methods

Water leaks may become unpleasant disclosures that regularly bear genuine and costly outcomes. To an astonishing number of individuals, be that as it may, a leaking fixture or a hairline split in a water pipe does little to cause caution, especially if the heft of the issue is taken cover behind a divider or underneath the ground.

For those acquainted with the range of harm that can possibly be brought about by water framework disappointments, water leak detection is considered as a real part of other critical home and building support speculations. This article plans to respond to a portion of the inquiries encompassing water leak detection and help those new to the procedure to see how significant it tends to be.

How to Detect Water Leaks

Current leak detection frameworks adopt a sound-based strategy to decide whether any of the pipes inside a water framework have been undermined. Utilizing a variety of sensors situated all through the framework even the subtlest sound of trickling water can be estimated and used to find the leak.

Sound, just as recurrence, is fundamental to finding the source and earnestness of the break, as water leaking at different weights yields various frequencies. The signs and recurrence got broken down by the framework and given to a certified expert who would then be able to utilize this and other data available to them to decide how best to address the leak.

The information the person surveys can assist them with organizing constrained assets, permitting them to quickly address genuinely undermined parts while deprioritizing less dire issues. The outcome is a very much kept up framework with the least measure of administration disturbances at the most minimal conceivable expense.

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Published By

Rajib Dey

www.constructioncost.co

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Pre Engineered Buildings (PEB)

Pre Engineered Buildings (PEB) are the buildings which are engineered at a factory and assembled at site. Typically PEBs are steel structures. Developed segments are manufactured at the factory to correct size, moved to site and assembled at site with catapulted associations. This sort of Structural Concept is commonly used to manufacture Industrial Buildings, Metro Stations, Warehouses and so on.

The adaptability of PEB in the spot of Conventional Steel Building plan ideas brought about numerous favorable circumstances, including economy and simpler manufacture.

These sort of building structures can be done inside to serve any capacities that are really helpful in a low ascent building plan. Instances of Pre-Engineered Buildings are distribution centers, Canopies, Factories, Bridges and so on.

Segments of PEB: Pre Engineered Buildings comprise diverse steel structural part which are as per the following,

1. Primary Frame: Primary surrounding of a PEB is a gathering of built up I-Shaped steel individuals and encircling brackets or castellated beams and so forth.
2. Secondary Structural Elements: It is really Cold Formed Members, which can be in diff. shapes like "Z", "C" and so forth. As a rule known as "Purlins".
3. Roof and Wall Panels : Tin conceals and Curtain Wall made of Glass and Roll-shaped steel sheets typically comes in this class.
4. Sandwich Panels: Sandwich Panel is made of three layers , in which a non-Aluminum Core is embedded b/w two aluminum sheet.
5. Different Accessories: Mezzanine floors, Bolts, Insulation, and so on.



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How to design Doubly Reinforced Beams

Concrete has quite high compressive strength, but low tensile strength. However, steel has very high tensile strength. That is why we insert steel reinforcements in the tension zones of a structure.

Now, you can provide reinforcements in concrete beams in two ways - single reinforcement (commonly used) and double reinforcement. Today, we will talk about doubly reinforced beams.

In case of doubly reinforced beams, steel reinforcements are inserted into both the tensile and compression zones of a beam. Meaning, at the top and the bottom of the beam. In contrast, the singly reinforced beams have reinforcements only at the bottom, where it needs tensile support.

Further, in singly reinforced beams, there are two steel bars to be provided, but you need not consider the moment of resistance. However, when you do need to consider this, you have to provide additional bars to reduce the tension in the over-reinforced section.

In case of doubly reinforced beams, though, the matter is quite different. In this case you will have to find out the moment of resistance first! Then, you need the area of tension steel (Ast) and area of compression steel (Asc). Combined, they would overcome the Excess Bending Moment (Mu2).

Designing doubly reinforced beams

When we begin designing a doubly reinforced beam, we need to be careful about some factors. For example, the depth of the beam may need to be limited to given values, be it for architectural reasons or otherwise.

If that is the case, you will have to implement the doubly reinforced beam with the requirement to resist more than standard limiting moment in that confined space you have for it. As a general rule of thumb, we design doubly reinforced beams when the go-to design moment of resistance is higher than that of the limiting moment of resistance.

The beam can be defined as a structural member that carries all vertical loads and resists bending. There are several types of materials used for beams, such as steel, wood, fibers, etc. But the most common material is reinforced concrete.



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Steel Pile Foundations

Precast piles and driven cast in piles utilize steel pipes. On account of precast or completely performed piles, there are two groupings, for example, empty little removal piles and solid piles. The empty little relocation piles utilize steel pipes when steel pile foundation is recommended. With regards to solid piles, steel H-piles are utilized.

On account of driven cast set up piles the fundamental arrangement is solid cylinder steel tube. If there should arise an occurrence of steel tubes, we utilize closed ended cylinder and open-ended cylinders.

Usually utilized steel piles are moved steel H area piles or pipe piles. The pipe piles have either an open or a closed end that is driven into the ground. I-segment or wide rib piles can likewise be utilized as pile foundation.

The H-sections are favored progressively over I-sections, as the H-segment has the same thickness for the web and the spine. On account of the I area, the thickness of the web is less contrasted with its spine thickness.

In the event that Q is the permissible auxiliary limit, A being the cross – sectional territory of the steel and the suitable worry of the steel given by fs, then:

Qall = A x fs

During the geotechnical examination the plan quality is resolved as Qdesign and this must be inside the Qall.

Types of Steel Pile Foundations

By and large, the steel piles can be sorted into the following categories: Screw Piles, Circle Piles, H-piles



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Different types of BBS shape codes for steel

Sami Ullah, the renowned civil engineer, presents this useful video tutorial in civil engineering youtube channel. In this video, the detail process is given for finding out the quantity of steel as well as shape codes for the steel bars.

Shape codes are considered as the basis of a proper bar bending schedule.

While going to estimate the reinforcement detailing for various members concerning a building, small bent ups and other angle detailing should be considered in the calculation to produce valid and cost-effective bar bending schedule.

It will significantly reduce the cost and wastage of reinforcement.

In beams & slabs there exist various bent ups, cuttings, and development lengths. Each and every bend and angle presented in the member is the outcome of design calculation. Therefore, these should be carefully enforced in practice.

For small projects, it is unnecessary to compute these details, just include a few more inches and work out the Bar Bending Schedule.



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Industrial Roof Trusses: Understanding and Designing

The industrial buildings such as godowns and factory floors are often low rise structures with few or none internal walls. In such buildings, special Care needs to be taken while designing industrial roof trusses, since large spans need to support the entire roofing system without intermittent support. Trusses with roof covering materials make up of the entire roofing assembly here.

What are Trusses?
Trusses are triangular formation of metal sections, usually used to span large lengths in space instead of solid girders. The external load apply mostly axial forces on the members in a truss. Depending upon how the force is applied, trusses can be designed in the following two ways:

Plane Trusses: where the external load is placed on the plane of the truss.

Space Trusses: where the external load can be applied to any three-dimensional space within.

How are Trusses Built?
Trusses mostly consist of axially loaded members to support loads. The reason for this that when steel members are subjected to axial forces, they perform better in bearing that load, than members that are in flexure. This is because the cross-section of such a system is uniformly stressed under axial forces.

Trusses are very common in most architecture. Mostly used to span long distances, they are well suited to bear the load of single-storey industrial buildings. They can also be designed to bear gravity loads in long span floors. For the same reason they are also mounted to bear loads of long span bridges.

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Steel Quality Field Test

It is essential for the constructors to have good quality material for their building project. Compromises in the quality of construction material can cause severe results leading to serious repercussions. One of the most important materials of a building is the steel reinforcements used in concrete columns, beams, and other structures.

The quality of steel received on site determines the strength of the structure with steel reinforcements inside it; so it is imperative that you check the steel quality right on the project site to ensure that your building will be made out of materials capable of handling the load.

Observations on Steel on Site:

1. Cleanliness: The reinforcements that you receive in the field must be clean ones. Dust, rust, earth, mild scales, paint, oil, grease or any similar coating clinging to the bars is detrimental to the bonding between reinforcement and concrete. Also, these contaminants can cause corrosion in the structure. For this reason, you must make sure that the steel bars and other reinforcements you receive are clean. Point to note: a little rusting on the bars is considered to be helpful in forming better bonds with the concrete. But excessive rusting and/or scaling is absolutely harmful for the building.

2. Manufacturer Marking: The bars should have their steel grade, manufacturer name/logo, brand name, diameter etc should be embossed on themselves. Do check if you have received everything of the same type as you expected.

3. Bending the Bars: When satisfied with the above, proceed to the Bend Test to examine the actual capabilities of the steel you have received on site, under realistic strain.

a. Bend Test: This test should be carried out as per the specifications in IS 1599 and you should use mandrels of size specified in IS 1786. The rebar sample should be bent in 180 degrees, results recorded, and then proceed to bending it 180 degrees.

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Details about structural and non structural defects in buildings

Concrete has diversified nature. It casts in place by including or excluding reinforcement. It is also precast or pre-stressed to attain necessary strength. For this purpose, there should be adequate knowledge on the behavior and constituents based on which the concrete is produced.

There should not be any type of laxity in any of its phase like placement, design & maintenance as these can create deterioration and resist concrete to accomplish its proposed functions. Given below, some vital factors which can weaken the quality of concrete:

1. Accidental loading
2. Chemical reaction like sulfate attack, alkali carbonate reactions, alkali silica reactions etc
3. Erosion of steel reinforcement
4. Inferior construction detailing

5. Erosion
6. Freezing and Thawing
7. Shrinkage
8. Settlement
9. Fire and weathering

Flaws in Building Design: Due to deficient structural design, the concrete is uncovered to flexural and shearing stresses and as a result spalling and cracking of concrete are developed. Any sudden modification in cross section of any member can result in raising the stress concentration in that member that leads to cracking of concrete.

Deflection is considered as one of the significant part in structural design. If there exist any issue in its consideration throughout design, that can produce cracking of concrete. Insufficient arrangement of drainage and expansion joints throughout the design also leads to deterioration and spalling of concrete.

Flaws During Construction: Flaws throughout building construction vary from inappropriate mixing, placing and curing of concrete. Detachment of shoring & formwork can also produces cracks in concrete.

When extra water is provided in concrete to enhance the workability of concrete, the water cement ratio is raised significantly and it can reduce the strength of concrete. Inappropriate alignment of formwork produces corrosion in concrete.

Structural Defects in Building Construction - The following structural defects are found in buildings:

1. Cracks in foundation (substructure)
2. Cracks in floors and slabs (superstructure)
3. Cracks in Walls (superstructure)

These above defects are occurred due to the following factors:

1. Inappropriate soil analysis
2. Inappropriate site selection
3. Application of defective materials
4. Inferior work

These structural issues can be resolved with perfect design and planning.

Non Structural Defects in Building Construction - The following non structural defects are common in buildings:

1. Defects in brick work
2. Dampness in old structures
3. Defects in plaster works

So, it is found that minimum design and construction defects lead to minor cracking or spalling which can weaken the concrete and result in collapsing of the structure. To get rid of these issues, proper care and attention should be taken in designing, detailing and construction of concrete structure.

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Some useful tips to measure loads on column, beam and slab

In order to work out the total load on columns, Beam and Slab, there should be clear ideas on the types of loads enforcing on the column.

Different Loads operating on Column:

1) Column Self Weight X Number of floors
2) Beams Self Weight per running meter
3) Load of walls per running meter
4) Total load on Slab (Dead load + Live load + Self weight)

Apart from above loading, the columns are also susceptible to bending moments which should be taken into consideration in the final design.

For Colomn: The Self weight of Concrete remains approx 2400 kg/m3, that is similar to 240 kN and self weight of steel is approx 8000 kg/m3.

Therefore, if we consider a column size of 230 mm x 600 mm with 1% steel and 3 meters standard height, the self weight of column is approx 1000 kg per floor that is equivalent to 10 kN.

At the time of making calculation, self weight of columns is taken as 10 to 15 kN per floor.

For Beam: Similar method is also used for making calculations of beam. Suppose, each meter of beam contains dimensions of 230 mm x 450 mm without slab thickness. Therefore, the self weight should be approx 2.5 kN per running meter.

For Walls: The Density of bricks differs among 1500 to 2000 kg per cubic meter. For a brick wall with thickness 6 inch, height 3 meter a length 1 meter. The load / running meter should be equivalent to 0.150 x 1 x 3 x 2000 = 900 kg, that is identical to 9 kN/meter. This method is useful for working out the load of brick per running meter for any brick type.

For aerated concrete blocks and autoclaved concrete blocks similar to Aerocon or Siporex, the weight per cubic meter should remain 550 to 700 kg per cubic meter.

When these blocks are utilized for construction, the wall loads for each running meter should remain as low as 4 kN/meter, the cost of the project is decreased considerably with the use of this block.

For Slab: Suppose, the slab contains thickness of 125 mm.

Therefore, self weight of each square meter of slab should be = 0.125 x 1 x 2400 = 300 kg that is identical to 3 kN.

Now, If finishing load is taken to be 1 kN per meter and superimposed live load to be 2 kN per meter. Therefore, from above data, the load of slab can be calculated as 6 to 7 kN approximately per square meter.

Factor of Safety: At the end, once the total load on a column is computed, consider the factor of safety that is very crucial for any building design for safe and convenient performance of building during its design life cycle.

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www.bimoutsourcing.com
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Some vital characteristics of concrete in fresh & hardened state

1. STRENGTH: Concrete has good strength against compression but it is moderately weak in tension and bending. Significant amount of force is required to crush concrete, but marginal force is required to pull it apart or produce bending cracks.

Compressive strength is mainly defined by the amount of cement applied, but is also influenced by the ratio of water to cement and proper mixing and placing as well as the suitability and range of hydration and curing.

Tensile strength generally varies from 7 or 8 % of compressive strength in high-strength mixes to 11 or 12% in low-strength mixes.

Both tensile strength and flexural bending strength are raised with the addition of steel or fiber reinforcement.

2. DURABILITY: Durability means the capacity to retain standard performance over an expanded service life.

Concrete upon which the commuters will walk on should have the resistance capacity against abrasion in order that it doesn’t erode easily.

Concrete uncovered on the outside of a building should have good resistance capacity against weather in order that it doesn’t lose it’s strength from recurring freezing and thawing.

The longevity of concrete uncovered to recurring freeze-thaw cycles can be raised greatly with air entrainment.

3. VOLUME STABILITY: All materials are enlarged and contracted with variations in temperature, and as the concrete is a porous material, it also enlarged and contracted with variations in moisture content. Cement-based products like concrete, concrete masonry, and stucco undergo initial shrinkage since the cement moisturizes and excess mixing water vaporizes.

This initial shrinkage is persistent, and it is other than reversible expansion and contraction resulting from later temperature or moisture variations.

Extreme shrinkage can lead to crack and as a result the moisture enters into concrete and a harmful cycle of deterioration is started.

4. WORKABILITY: Workability belongs to the relative ease with which a fresh concrete mix is treated, arranged, compacted, and finished devoid of segregation or separation of the materials.

Proper workability is necessary to form inexpensive and superior quality concrete.

Fresh concrete contains strong workability if it can be developed, compacted, and finished to its final shape and texture with least effort and devoid of segregation of the materials.

Concrete having inferior workability fails to flow smoothly into forms and perfectly enclose reinforcing steel and embedded items, and it becomes complicated to compact and finish.

5. CONSISTENCY: Consistency stands for the aspect of workability associated with the flow characteristics of fresh concrete.

It signifies the fluidity or wetness of a mix and is computed with the slump test. Fresh concrete is arranged in a metal cone. When the cone is detached, the concrete slumps a specific amount on the basis of how fluid it is. A wet, soft mix slumps more as compared to a drier, stiffer one.

A high-slump concrete is very fluid whereas a low-slump concrete is drier and more hard.

A high-slump mix leads to unnecessary bleeding, shrinkage, cracking, and dusting of the hardened concrete surface.

6. COHESIVENESS: Cohesiveness means the element of workability which specifies whether a mix is harsh, sticky, or plastic.

Plasticity is a suitable property in concrete stating that a mix can be moulded and retained a shape at the time of being formed.

A harsh mix does not have plasticity and the materials may be easily detached.

Harshness is resulting from either excessive or shortage of mixing water (high- or low-slump mixes), a shortage of cement (lean mixes), or a shortage of fine aggregate particles.

Harshness may also occur by an excess of rough, angular, flat, or elongated aggregate particles. Harsh mixes can sometimes be enhanced with air entrainment or by raising the fine aggregate or cement content, but modifications should be done to the overall mix to sustain the exact ratios of all materials.

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Basic differences among RC slab and RB slab

RC Slab: RC Slab stands for a horizontal structural component of steel reinforced concrete. Generally, the thickness of RC slab varies from 100mm to 500mm. RC Slabs are frequently applied as floorings, ceilings etc. Slabs are supported on two sides only or contain beams on all four sides.

RC slabs are erected with formwork, that is generally created with wooden planks, boards, plastic & steel. In recent times, prefabricated RC slabs are also utilized. RC Slab is also termed as Reinforced Concrete Slab that arranges reinforcement for retaining the strength of the structure. Straight bar and alternative cranked bars are also applied as reinforcement in the RC slabs.

RB slabs: RB slab stands for a reinforced brick slab that is suitable for floorings and ceilings. RB slab is erected with steel reinforcement arranging spacing with the bricks. The construction cost of RB slab is less with regard to RC slab.

An RC slab alias Reinforced Cement slab is found in buildings and in bridge construction. The reinforcement is provided with steel bars which are arranged with some distances according to design and based on the load the slab has to undergo.

An RB slab alias Reinforced Brick slab is ideal for roofs in buildings. It is less costly as compared to RC slabs. The reinforcement is provided with steel bars which are arranged with some distances according to design and based on the load the slab has to undergo.

The distance among the bars is occupied by bricks which are arranged on its edge. The depth of the slab remains 4.5 in. The bars are provided among the bricks in both directions. The cement-sand mortar along with least possible water quantity is used to fill up the distance among the bars.

As bricks are permeable, the slab should be plastered with cement-sand plaster having a water-proofing compound added on the upper surface. On the bottom part of the slab, the plaster should be done with a cement-sand plaster for superior look.

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Some best formwork methods

Formwork means the temporary or permanent molds which are applied to retain wet concrete unless it gets cured. It is a vital component in concrete construction as without formwork the schedule, labor requirements, quality and total cost of a project are significantly impacted.

In due course of time, formwork molds have changed from conventional job-built timber to pre-engineered systems comprising of a combination of steel, aluminum, manufactured timber, plywood and plastics.

These improvements in formwork molds make the jobsite production & safety better, with fewer labor, whereas creating a superior finished product.

Walls—Now-a-days, steel-framed, wood-faced panels, which need consumable ties at 2-feet-on-center and one connection per square foot, are extensively used for handset wall forming. These are substituted with larger, two-person handset systems which need less labor and get rid of consumable purchases due to reusable taper ties.

In recent times, clamp connection forms having wood or plastic form faces that offer tremendous labor savings in assembly, are utilized. Assembly and reconfiguration of these standard systems to satisfy changeable structure dimension takes place instantly, and also offers a consistent concrete finish.

Slabs—The application of fixed or tailor-made wood posts, stringers and joists is still considered as the most common method of shoring of slabs. This method delivers from generation to generation and considerable labor is required for that. Since, the posts are arranged as close as 2-feet-on-center, construction sites turn out to be very congested.

A new construction method that highlights engineered lumber and metal posts raise the post spacing up to 5 feet by 10 feet and suggests components which are systematic and can be reprocessed. This increases spacing and facilitates less material on site to develop the same slab area. Less material leads to lowered handling requirements, less labor to arrange and strip the formwork, fewer transport costs, and an improve overall job site productivity.

The existing method for gang-forming slabs applied trusses or structural decks based on significant amount of time for assembly and disassembly. Besides, this method requires a huge amount of crane time, thus accelerating the time for resetting a suitable operating method. The customer should also purchase the plywood facing and often restore it several times on the same project.

Gang-forming slabs are commonly found on the structures with height in excess of 15 stories with the purpose of reducing cost. To provide a greater solution to these types of systems, smaller tables are arranged to the job site fully assembled with plywood especially for mid-rise buildings where gang-forming was not inexpensive earlier.

The formwork-lifting elevators affixed to the exterior of a building that facilitates all formwork to be cycled from floor to floor devoid of requiring a crane to decrease job site crane time & formwork labor requirements. These table-lifting systems are applied along with the smaller table method and also allow for other construction material like handset shoring, vertical formwork and reshores from below to cycle from floor to floor with a crane.

How to choose the exact formwork

Structural engineers should be aware that concrete contractors carry out a detailed analysis of available formwork solutions to arrange the best system for the construction project since conditions differ for each individual project, there is no simple formula for the selection of the proper formwork supplier or system.

Generally, formwork should include 40- to 60-percent of the total cost of a building’s structural concrete frame. For concrete walls, the cost remains 50- to 60-percent range. These percentages involve the cost of material and labor, with the largest cost being for labor. It is vital to analyze the labor costs comprehensively since it is the higher expenditure and is that amount is decreased, it offers superior effect on the bottom line.

To provide the most effective solution for a project, a contractor will calculate different forming systems. Since the scarcity of available and capable labor continues, it has become even more important to opt for proper forming system. So, there are two options for a contractor - a low-priced forming material that is labor-intensive or a forming system that is costly but offer high productivity.

To get more details, go through the following link csengineermag.com



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On site demonstration on setting up formwork for concrete beam construction

Formwork in concrete construction is nothing but a mold for a structure where fresh concrete is poured with the purpose of solidifying it consequently. Formwork is temporary structure and generally it is not demonstrated in the drawings. Types of formwork for concrete construction are based on the material of formwork as well as type of structural element.

Formworks is also categorized on the basis of the type of structural member construction like slab formwork to be applied in slab, beam formwork, column formwork to be applied in beams and columns respectively.

Formwork Materials.

• Wood
• Either all-wood or some wood components
• Plywood
• Aluminum
• Steel
• Plastics

In this construction video tutorial, one can learn how to arrange formwork for concrete beam construction.

Beam formwork is generally formed with either timber or metal panels. In this type of formwork, the process is to produce a box surrounded with frames at the perfect size of the beam and fasten it firmly on the kicker left from base or at the last phase of beam concreting. The box is detained in exact position with steel column clamps or bolted yokes and supported with timber studs or props.

Consideration should be given on the following points for formwork construction It is hard enough to resist all types of dead and live loads.

It should be built up tightly and sustained competently and braced both horizontally and vertically with the intension of preserving its shape.

The joints in the formwork should be firm against seepage of cement grout.

The formwork should be arranged correctly to the preferred line and levels with plane surface.

The material of the formwork should not be twisted when comes in contact with the elements.

It should be supported with firm base.

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DETAILS OF ONE WAY SLAB REINFORCEMENT

Reinforcement detailing of a slab is performed on the basis of its support conditions. Support to slab is generally provided through walls or beams or columns.

A slab is called one way if the supported is provided from two opposite edges. So, the prime load is transmitted onward the spanning direction. Here, the proportion of longer extent to shorter extent is over 2. In one way slab, one side is greater than the other one. In one way slab, the bending occurs mainly in one direction only (spanning direction).

Consequently, the main reinforcement is necessary to withstand the moments produced and designed for the same. The main reinforcement is arranged at the bottom of the slab that is usually described as the tension face.

In one way slab, as one side is larger as compared to the other one, the greatest load is carried by the larger side. To give more support on the larger side, main reinforcement is set perpendicular to that side or parallel to the shorter direction. Distribution steel is arranged in the extended direction that will not be very useful for carrying any load.

In one way slab, the main reinforcement is calculated with a formula (In limit state design) and to obtain the result the comparison is made between the comparing compressive force and tensile forces.

Ast = 0.5 Fck/Fu[1-√1-2.6Mu/Fck.b.d]b.d

and the distribution steel is calculated as

0.15% of Ag, for mild steel.

0.12% of Ag, for tor steel.

Where, Ast denotes Area of the steel in tension.

Fu denotes Ultimate strength of steel.

Mu denotes Ultimate moment of resistance.

b denotes Breadth of the slab section.

d denotes Depth of the slab section.

Ag denotes Gross area of the section.

Article Source : www.dailycivil.com

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www.constructioncost.co

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How to place stirrups with proper structural drawings in a column

This construction video is recorded on the topic of how to organize stirrups for a column that contains 12nos of vertical bar. Learn to apply various structural drawings for organizing stirrups.

Stirrup can be defined as follows :-

1. A reinforcement useful for withstanding shear and diagonal tension stresses in a concrete structural member.

2. A steel bar that is curved into a "U" or box shape and arranged perpendicular to, or at an angle to the longitudinal reinforcement, and perfectly anchored.

3. Lateral reinforcement that is developed with separate units, open or closed, or of uninterruptedly wound reinforcement. The word stirrups is generally used with lateral reinforcement in flexural members and the term is linked with lateral reinforcement in vertical compression members.

Concrete beams contain different depth. If the beam contains more depth, the shear strength will be increased. If the depth is insufficient, steel stirrups should be included to enhance the shear strength of the beam. These stirrups generally refer to one piece of steel that is curved into a quadrilateral shape. Generally small diameter steel like #3 and #4 rebar is applied. The stirrup normally covers around the bottom and top bars of the beams.

As the stirrup is built up from two pieces having insufficient lap splice, it is recommended to set up a stirrup simultaneously when the horizontal reinforcement is being set up.

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How to design R.C.C lintels

Now-a-days, the R.C.C lintels are mostly recognized to extent the openings for doors, windows, etc. in a structure owing to their firmness, inflexibility, fire resistance power, cost-effectiveness and simplicity in construction. R.C.C lintels are recommended for all the loads and for any span. The width of lintel is similar to width of wall. Depth of lintel is based on the length of span and magnitude of loading.

Lintel can be made from various materials. Such as steel, wood, stone, RCC, etc.

Generally, the most effective material for lintel is RCC (Reinforced Cement Concrete). Generally, applied concrete ratio for RCC lintel is 1:2:4.

On the basis of the casting methods, RCC lintel is classified as Pre-cast RCC lintel and Cast-in-place RCC lintel.

DESIGN METHOD OF R.C.C LINTEL

There are similarities between the design methods of a lintel (single span or continuous having a few openings) and the design methods of a simple beam.

1. The lintel width is same as the wall thickness.

2. Provide an appropriate depth of the lintel.

3. Select the operational span of the lintel (maintain rational end bearings and real depth).

4. Assume W as the aggregate weight of the masonry work wrapped in the triangle, supposing that conditions authorize triangular load of the workmanship on the lintel.

5. Estimate the extreme bending moment (M1) at the centre of the lintel ( because of the triangular load).

M1 = Wl/6

Now estimate the maximum bending moment (M2) because of the self-weight (w) of the lintel per metre length.

M2 = wl^2/8

To read the complete article, go through the following link www.dailycivil.com

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Detailed process for measuring weight of steel

This is a useful video for construction professionals. The video will teach you how to estimate weight of steel. In this video, two diverse formulas are applied – Density Method and D square /162 Method.

Density refers to the mass of an object that is divided with its volume. Density frequently contains units of grams per cubic centimeter (g/cm3). Keep in mind, grams mean a mass and cubic centimeters mean a volume (the identical volume as 1 milliliter).

As density is mass per unit volume, the density of a metal is measured by submerging it in an identified amount of water and computing how much the water increases. It is the volume of the metal. Its mass is calculated with a scale. The unit for density is gm/cm3.

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