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Thursday, February 21, 2019

Some useful guidelines to work out the total loads on a column & footing

This article is about calculation of loads for column and footings design.
The following types of loads operate on a column :-
1. Self weight of the column x Number of floors
2. Self weight of beams per running meter
3. Load of walls per running meter
4. Total Load of slab (Dead load + Live load + Self weight)
The columns are also susceptible to bending moments which should be included in creating the final design. There are different types of advanced structural design software like ETABS or STAAD Pro which can be applied to design a good structure efficiently. The calculation for structural loading In professional practice is based on some fundamental assumptions.
For Columns: Self weight of Concrete is approximately 2400 kg per cubic meter that is identical to 240 kN. Self weight of Steel is approximately 8000 kg per cubic meter. Suppose a large column having size of 230 mm x 600 mm with 1% steel and 3 meters standard height, the self weight of column is approximately 1000 kg per floor, that is identical to 10 kN. So, here, the self weight of column is taken as among 10 to 15 kN per floor.
For Beams: The calculation is same as above. Suppose, each meter of beam contains dimensions of 230 mm x 450 mm exclusive of slab thickness. So, the self weight is approximately 2.5 kN per running meter.
For Walls: Density of bricks differs among 1500 to 2000 kg per cubic meter. For a 6″ thick wall with 3 meter height and 1 meter length, the load can be measured per running meter equivalent to 0.150 x 1 x 3 x 2000 = 900 kg which is equivalent to 9 kN/meter. The load per running meter can be measured for any brick type by following this method.
For autoclaved, aerated concrete blocks like Aerocon or Siporex, the weight per cubic meter should remain among 550 to 700 kg per cubic meter. If these blocks are utilized for construction, the wall loads per running meter remains as low as 4 kN/meter, that leads to cutback in construction cost.
For Slab: Suppose the thickness of the slab is 125 mm. Now, each square meter of slab contains a self weight of 0.125 x 1 x 2400 = 300 kg that is similar to 3 kN. Suppose, the finishing load is 1 kN per meter and superimposed live load is 2 kN per meter. So, the slab load should remain 6 to 7 kN per square meter.
Factor of Safety: Finally, once the calculation of the entire load on a column is completed, the factor of safety should also be taken into consideration. For IS 456:2000, the factor of safety is 1.5.
Some useful guidelines to work out the total loads on a column & footing

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Published By
Rajib Dey
www.constructioncost.co
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Wednesday, February 20, 2019

Some useful tips to enhance the longevity of concrete piles

If concrete is mixed perfectly and compacted to a solid impervious, the longevity of all the construction materials is significantly increased in a non aggressive atmosphere.

The strength of concrete is influenced by sulphate and sulfuric acid that takes place normally in soils, erosive chemicals existent in industrial waste in fill materials and organic acids and carbon dioxide existent in ground water.

A solid, properly compacted concrete can efficiently safeguard the concrete piles, pile cap and ground beams against the attack by sulphates. The low penetrability of dense concrete resists or significantly controls the ingress of the sulphates into the pore spaces of the concrete.

That's why high strength precast concrete piles are mostly recommended for application. Although these are not acceptable for all the site conditions and bored cast in situ / driven cast in situ piles, so, at the time of application, these should be designed perfectly to attain necessary degree of impenetrability and defiance to aggressive action.

Both high alumina cement and super sulphated cement are not suitable for piling work. As an alternative, reliance is provided on the resistance of solid impervious concrete that is formed with a low water cement ratio. Coating of tar or bitumen on the surface, metal sheeting or glass fibre wrapping filled with bitumen may be chosen.

A layer of heavy gauge polythene sheeting provided on a sand carpet or on blinding concrete is arranged to safeguard pile caps and ground beams on the underside. The vertical sides are safeguarded once the formwork is eliminated with the use of hot bitumen spray coats, bituminous paint, trowelled on mastic asphalt or adhesive plastic sheeting.

Preventative measures against the aggressive action caused by sea water on concrete should only be taken into consideration with regard to precast concrete piles. Cast in situ concrete is utilized only as a centering to steel tubes or cylindrical precast concrete shell pills. The precast concrete piles for marine condition, a minimum ordinary portland cement content of 360 kg/m3 and a maximum water cement ratio of 0.45 by weight should be chosen.

Some useful tips to enhance the longevity of concrete piles

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Published By
Rajib Dey
www.constructioncost.co
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Tuesday, February 19, 2019

How to measure superimposed loads on a column

The objective of a column is to withstand axial and lateral forces and transmit them securely to the footings in the ground.

In this exclusive article, you will learn how to work out the superimposed loads on a column in a structure with some easy-to-follow steps.

Columns provide support to the floors in a structure. Slabs and beams transmit the stresses to the columns. So, it is crucial to make a strong column.

A column stands for a compression member, the effective length of which surpasses three times the minimum lateral dimension. Compression members whose lengths remain under three times the minimum lateral dimension, are constructed with plain concrete.

The axial load bearing strength of a column is derived from the follwoing formula :-

Reinforced Concrete Columns

Besides, axial loads, the column design is dependent on several other factors. Because of beam spans, wind loads, seismic loads, point loads and various other factors, the bending moments and tortional forces are produced.

A column is categorized on the basis of various factors :-

1. Depending on shape
• Rectangle
• Square
• Circular
• Polygon


2. Depending on slenderness ratio: The ratio of the effective length of a column to the minimum radius of gyration of its cross section is known as the slenderness ratio.

• Short RCC column, =< 10
• Long RCC column, > 10
• Short Steel column, =<50
• Intermediate Steel column >50 & <200
• Long Steel column >200


3. Depending on the type of loading
• Axially loaded column
• A column subjected to axial load and unaxial bending
• A column subjected to axial load and biaxial bending


4. Depending on pattern of lateral reinforcement
• Tied RCC columns
• Spiral RCC columns


Least eccentricity
Emin > l/500 + D/30 >20
Where, l denotes unsupported length of column in ‘mm’
D = lateral dimensions of column


The following types of Reinforcements for columns are found :-

Longitudinal Reinforcement
• Least area of cross-section of longitudinal bars should be minimum 0.8% of gross section area of the column.
• Maximum area of cross-section of longitudinal bars should not be in excess of 6% of the gross cross-section area of the column.
• The bars should not be below 12mm in diameter.
• Least number of longitudinal bars should be 4 in rectangular column and 6 in circular column.
• Distance of longitudinal bars measured along the perimeter of a column should not go above 300mm.


Transverse reinforcement
• It may appear in the form of lateral ties or spirals.
• The diameter of the lateral ties should not remain below 1/4th of the diameter of the greatest longitudinal bar and in no case below 6mm.


The pitch of lateral ties should not go beyond
• Minimum lateral dimension
• 16 x diameter of longitudinal bars (small) • 300mm


Helical Reinforcement
The diameter of helical bars should not remain below 1/4th the diameter of largest longitudinal and not below 6mm.
The pitch should not go above (if helical reinforcement is permitted);
• 75mm
• 1/6th of the core diameter of the column


Pitch should not remain under,
• 25mm
• 3 x diameter of helical bar
Pitch should not surpass (if helical reinforcement is not permitted)


Least lateral dimension
• 16 x diameter of longitudinal bar (smaller)
• 300mm


Reinforced Concrete Columns

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Published By
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Monday, February 18, 2019

Different components of super structure

Superstructure stands for segments of the structure that is situated over the surface of the ground. The superstructure is built with different sections of walls, roof, doors, and windows, flooring. The sections of the structure situated on the grounds and underneath the ground floor level are known as the plinth.

The objective of superstructure is to bear different types of loads operating on the structure which range from dead load, live, load, wind load etc. These loads are then transferred to the underlying soil through the substructure.

Each element of superstructure is applied as a specific purpose, but the prime function is to arrange privacy, safety to the inhabitants. Wall and roof safeguards from the surrounding, doors permit entry and give safety, windows arrange requisite sunlight and fresh air and floor provides a leveled surface to live and protection from beneath.

Building superstructure

Column: A column in structural engineering stands for a vertical structural component that disperses the weight of the structure over to other structural components underneath , through compression.

Floor: A floor normally comprises of a support structure known as a sub-floor on top on which a floor cover is placed to arrange a walking surface.

Roof wall :

Flat – Should contain a slight slope for drainage

Shed – A single slope

Gable – Two slopes intersect at a ridge. Two walls expand up to the ridge.

Hip – Two gables, a pyramid is treated as a hip roof.

Gambrel – Four slopes in one direction, the usual barn roof.

Mansard – A four-sided gambrel-style hip roof formed with two slopes on each of its sides with the lower slope, perforated by dormer windows, at a steeper angle than the upper.

Beam: Beam stands for an inflexible structural member formed to bear and transmit transverse loads across space to supporting components.

Different components of super structure

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Published By
Rajib Dey
www.constructioncost.co
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Saturday, February 16, 2019

Common structural members in a building

In this civil engineering article, you will get detail information on different types of structural members in a building.

Beam: Beam stands for a flexure member of the structure. It is exposed to transverse loading like vertical loads, and gravity loads. With these loads, shear and bending are formed inside the beam. Beams belong to horizontal structural members to bear a load successfully.

Beam is generally applied for withstanding vertical loads, shear forces and bending moments.

Columns: A long vertical member that mostly undergoes compressive loads & buckling loads is known as column. Columns stand for vertical, structural members of a structure. They transmit load from beams to footings. Columns are mostly utilized to support beams or arches on which the upper sections of walls or ceilings rest.

Strut: Strut is a compressive member of a structure. This structural member is driven from opposite ends. The purpose of a strut is to withstand compression.

Ties: A tie stands for a structural member that is extended from opposite ends. A tie mainly deals with tension.

Beam-Column: A structural member that is exposed to compression and flexure is known as beam column.

Grid: A group of beams which overlap each other at right angles and exposed to vertical loads is known as grid.

Cables and Arches: Cables are normally suspended at their ends and are granted to sag. The forces then turn to pure tension and are headed along the axis of the cable. Arches have the similarity with cables apart from they are inverted. They bear compressive loads which are directed along the axis of the arch.

Plates and Slabs: Plates belong to three dimensional flat structural components generally constructed with metal which are frequently utilized in floors and roofs of structures. Slabs are identical to plates apart from that they are normally constructed with concrete.

Common structural members in a building

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Published By
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www.constructioncost.co
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Friday, February 15, 2019

POLEFDN – A excel based construction program for pole foundation analysis

POLEFDN is a MS-excel based spreadsheet program that can be used for making analysis of a pole foundation on the assumption of the application of a inflexible round pier that is supposed free (unrestrained) at the top and exposed to lateral and vertical loads. The spreadsheet particularly makes calculation for the necessary embedment depth, the maximum moment and shear, the plain concrete stresses, and the soil bearing pressures.

This program stands for a workbook that comprises of the following six (6) worksheets:

• Doc - Documentation sheet
• Pole Fdn (Czerniak) - Pole foundation analysis for free-top round piers with PCA/Czerniak method
• Pole Fdn (UBC-IBC) - Pole foundation analysis for free-top round piers with UBC/IBC method
• Pole Fdn (OAAA) - Pole foundation analysis for free-top round piers with OAAA method

• Granular Soil (Teng) - Pole foundation analysis in granular soil with USS/Teng method
• Cohesive Soil (Teng) - Pole foundation analysis in cohesive soil with USS/Teng method


Given below, some useful features of the program :-

This program can deal with both horizontally and vertically applied loads. The vertical load may contain an associated eccentricity that leads to an additional overturning moment to be always assumed to add directly to the overturning moment formed with the horizontal load.

This program guesses that the top of the pier remains at or over the top of the ground surface level.

This program guesses that the actual resisting surface remains at or under the ground surface level. It takes into account any weak soil or any soil that is detached at the top.

The "Pole Fdn(Czerniak)" worksheet guesses that the inflexible pier rotates about a point situated at a distance, 'a', under resisting the surface. The highest shear in pier is supposed to be at that 'a' distance, whereas the maximum moment in the pier is supposed to be at a distance = 'a/2'.

The "Pole Fdn(Czerniak)" worksheet works out the "plain" (unreinforced) concrete stresses, compression, tension, and shear in the pier. The corresponding permissible stresses are also set on the basis of the strength (f'c) of the concrete. It is performed to check whether the steel reinforcing is actually necessary or not. The permissible tension stress in "plain" concrete is supposed to be equivalent to 10% of the value of the permissible compressive stress.

The "Pole Fdn(Czerniak)" worksheet measures the actual soil bearing pressures along the side of the pier at equivalent distances to 'a/2' and 'L'. The relevant permissible passive pressures at those locations are set for comparison.

As all overturning loads are protected with the passive pressure against the embedment of the pier, this program guesses that the pier functions in direct end bearing to withstand only the vertical loading. The bottom of pier bearing pressure is measured that contains the self-weight of the pier, assumed at 0.150 kcf for the concrete.

To download the program, click on the following link www.cesdb.com

POLEFDN – A excel based construction program for pole foundation analysis

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Published By
Rajib Dey
www.constructioncost.co
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Thursday, February 14, 2019

Plaster of Paris In Construction – Uses and Benefits

Plaster of Paris (POP) is a elementary building material that is mainly applied for coating walls and ceilings as well as for making architectural designs. It comes as dry powder and gets solidified when used along with water and heat.

The following types of plaster of paris is mainly available :-

a. Plaster of paris (Gypsum)
b. Lime Plaster
c. Cement Plaster


POP is originated by incomplete calcination of gypsum or calcium sulfate at 100 – 190 degree C without any admixture. The setting time is 5 – 20 min.

Benefits of Plaster of Paris:

1. It is light in weight and long lasting.
2. It contains low thermal conductivity.
3. It has strong resistance capacity against fire and it is considered as a very good heat insulating material.

4. It does not shrink at the time of setting and as a result it does not form cracks at the time of heating or setting.
5. It develops a thick surface to withstand normal knocks once drying is completed.
6. It blends easily with water and disperses quickly and level.
7. It contains good adhesion on fibrous materials.
8. It provides a solid surface on which the colours are set.

9. It does not provide any chemical action on paint and does not produce alkali attack.
10. Plaster of Paris provides a elegant interior finish. Due to inclusion of gypsum in POP, there is lot of shine and smoothness.
11. It can be easily changed into any shape.


Drawbacks of Plaster of Paris:

1. Gypsum plaster is not recommended for exterior finish as it is dissolved in water to some extent.
2. It’s cost is high as compared to cement or cement lime plaster.
3. It cannot be applied in moist situations.
4. Skilled labor should be appointed for proper application and consequently huge labour cost is required for using plaster of Paris.


Plaster of Paris In Construction – Uses and Benefits

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Published By
Rajib Dey
www.constructioncost.co
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Wednesday, February 13, 2019

Principles of chain surveying

Chain survey belongs to the easiest method of surveying. Under this type of survey, only measurements are captured in the construction site, and the other works, like plotting measurement etc. are carried out in the office. Irrespective of angular measurements, only linear measurements are undertaken. It is mostly effective for small plane areas having very few details. If it is performed efficiently, it provides quite perfect results.

To conduct this survey, the following items are required in job site - Chain, Tape, Ranging-Rod, Arrows, Cross staff

Relevance of Chain Survey - Chain survey can be undertaken for the following purposes:

1. The area required to conduct survey is relatively small
2. The ground is level to some extent
3. The area is open and
4. Details to be gathered are simple and less.


Survey Station - Survey stations are categorized as follow : Main Stations, Subsidiary or tie

Main Stations: Main stations refer to the end of the lines, which manage the boundaries of the survey, and the lines which attach the main stations remind of the main survey line or the chain lines.

Subsidiary or the tie stations: Subsidiary or the tie stations belong to the points chosen on the main survey lines, where it is important to trace the interior detail like fences, hedges, building etc.

Tie or subsidiary lines: A tie line connects two fixed points on the main survey lines. It facilitates to verify the exactness of surveying as well as trace the interior details. The location of each tie line should be adjacent to some features, like paths, building etc.

Base Lines: It is the primary and longest line, which moves roughly through the center of the field. All the other measurements to demonstrate the details of the work are obtained relating to this line.

Check Line: A check-line also called as proof-line belongs to a line that attaches the apex of a triangle to some fixed points on any two sides of a triangle. A check-line is calculated to verify the exactness of the framework. The length of a checking line, as calculated on the ground should satisfy its length on the plan.

Offsets: Offsets stand for the lateral measurements from the baseline to secure the positions of the several objects of the work in relation to the baseline. These are normally set at right angle offsets. It is also drawn by applying a tape.

Chain survey method:
1. Reconnaissance: The initial examination of the area prepared for survey is known as reconnaissance. The surveyor examines the area to be surveyed as well as arranges index sketch or key plan.
2. Marking Station: Surveyor settles the required no of stations at areas from where maximum possible stations can be arranged.


The marking is done with the following processes:

a. Setting ranging poles
b. Pushing pegs
c. Marking a cross if the ground is solid
d. Digging and setting a stone.


3. After that, the surveyor chooses the way for transforming the main line, that should be horizontal and dirt free as possible and should move around through the center of work.
4. Then ranging roads are secured on the stations.
5. As soon as the stations are fixed, chaining should be done.
6. Create ranging wherever required.
7. Work out the change and offset.
8. Enter in the field the book.


Principles of chain surveying

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Published By
Rajib Dey
www.constructioncost.co
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Tuesday, February 12, 2019

Some outstanding ideas to design your home with Concrete

Besides, concrete, other materials like steel, fibre, plastic, glass, wood and other superior materials can also be used together with concrete to build up homes. Now-a-days, concrete is extensively utilized for the construction of commercial, residential, institutional, and industrial buildings due to it’s adaptability, cost-effectiveness and the easy accessibility of raw materials for production.

In recent times, concrete home construction is gaining popularity because of the factors like sustainability, green building, disaster resistance, energy conservation, and safety. To satisfy these requirements efficiently, the engineers offer some unique design ideas.

Concrete Home Design Ideas: Designers have provided different types of design ideas for the construction of concrete homes owing to its versatility and easy accessibility of construction materials. Motivations that put into effect or head over to new design ideas are dissimilar, as for example, some design ideas get inspiration from nature while some from energy efficiency, aesthetics, sustainability, and recycling materials.

Advantages of Concrete Homes:

1. Stable
One of the most outstanding properties of concrete is its strength which offers comfortable shelter from inclement weather, and minimizes property damage while safeguarding from severe weather and natural disasters.


2. Long-lasting
Future maintenance is not required for home as a result the construction cost is reduced significantly.


3. Adaptable
Concrete is a multifaceted material from which any shape and form can be developed. This features facilitates the designers to produce innovative designs on the basis of the demand of client and situations under considerations.


4. Eco-Friendly
The materials necessary to develop concrete are accessible in local areas. Recycled materials like recycled aggregate, pozzolanic cementitious materials like fly ash and silica fumes are utilized to build up concrete.


It results in decreasing CO2 emission throughout cement production since a smaller quantity of cement is required for production.

5. Advantages throughout life-cycle of the Structure
Concrete homes offer various advantages and benefits all through their life span. As for example, chills inside area of the house and consequently curtail energy consumption, and give protection against disasters like fire; hurricane; earthquake; and flood.


Besides, concrete contains low volatile organic compound and it does not impact indoor air quality. Finally, it can be recycled to develop recycled concrete aggregate.

To get some of the most outstanding and award-winning design ideas for construction of concrete homes, click on the following link theconstructor.org

Some outstanding ideas to design your home with Concrete

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Published By
Rajib Dey
www.constructioncost.co
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Monday, February 11, 2019

Why curing of concrete is important?

Curing offers the following functionalities :

1. Resist the concrete from getting dried throughout hydration. If this happens, the strength of the concrete is reduced significantly. The damage can’t be recovered. If concrete is dried, the cement grains will produce an impervious layer of hydration product around them, and it will resist recurring of hydration, though several occasion it is dampened again.

2. To maintain heat at the surface.

Curing is carried out for the following purposes :-

a. To get rid of frost damage (under 5°C, 40°F)
b. To raise initial strength
c. To minimize temperature gradients


When low temperatures decrease initial strength, the effect does not remain for a long time in case the concrete has not frozen, and it is consequently retained at higher temperatures. As a result, a sample that is retained at 5°C (40°F) will not completely hydrate (specifically if there exist a pozzolan in it), but even after a number of months it will hydrate again with higher temperature.

Since hydration occurs more slowly, cements containing pozzolans and GGBS normally need longer curing. It is therefore necessary that these concretes should be recognized on site, and cured sufficiently. The pozzolanic reaction will then produce extra hydration products to block some of the pores among the cement grains, and attain good strength.

Given below, some recognized process of curing :

• Cover materials (e.g., columns) in polythene once the shutters are detached.
• Spray with curing membrane as soon as detachment of shutters.
• Wrap slabs with polythene (and pour ground slabs on polythene).
• For heat retention, the polystyrene should be utilized on the back of shutters (particularly, steel ones)
• Just leave shutters in exact position for a few extra days (particularly wooden ones).
• 50 mm of sand is well suited on slabs.
• Ponding (i.e., developing a pool on the concrete surface) will be definitely most suitable.


Note about curing:

• Ensure that curing is provided immediately as possible. A few hours may provide significant effect.
• Spray-on curing membranes are less effective, and in windy conditions they should not be used. On complicated areas (like columns), they should be used as there is no other options.
• Keep in mind that PFA, GGBS and, especially, CSF requires much better curing (frequently 5 days, in spite of 3 days).
• Allowing the bleed water to dry off will lead to more bleeding, and plastic cracking.
• Slabs on ground should contain a polythene sheet that is arranged under them, to get rid of excessive water absorption with dry soils.


Why curing of concrete is important?

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Published By
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www.constructioncost.co
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Friday, February 8, 2019

Types of plasticizers commonly used and their benefits

Plasticizers & super-plasticizers facilitate concrete to enhance it's workability.

Due to it’s strong fluidity, shotcrete is highly beneficial. When the homogeneous mix is applied pneumatically, it simply conforms with even rugged surfaces whereas maintaining the initial resistance to compression to offer good structural support from the beginning.

A family of chemical polymers like plasticizers and super-plasticizers are liable for the material’s fluidity. These are also called water reducers to minimize the total water-to-cement ratio, providing it a more ‘liquid’ consistency devoid of diluting the mix with water.

These additives are normally added all through the mixing process and allow the concrete mix to become yielding until application keeping its consistency unchanged.

Plasticizers and super-plasticizers provide a temporary dispersing effect, that produces a comprehensive hydration of each cement particle, making the fluidity of the mix better.

This mix is amalgamated with volcanic fly ash to form the type of hydraulic concrete, a fully hardy and weatherproof material along with extremely erosive salt water.

Plasticizers: first steps - First generation of plasticizers is known as Lignosulphonates. It belongs to a byproduct originated from wood processing that is frequently applied in recent times to form a workable mix with only basic raw materials.

These additives, known as Mid-Range Water Reducers [MRWR] affix themselves to the surface of a cement particle, that bears both positive and negative charges. Plasticizer polymers, which are negatively charged, neutralize the positive charges on the cement surface, transforming the entire surface completely negative.

It causes a physical effect that allows the negatively charged cement particles to keep away each other, providing a dispersing effect to develop better water infiltration. This mix can now function well devoid of adding more water, and allows for a cutback in the overall amount of water necessary, reducing the water-cement ratio by around 10%.

But these additives can defer the curing process, which may sequentially produce further complicacies. If curing is not done within a certain timeframe, a greater amount of hydrostatic pressure could amass in a formwork column over a long lasting period, causing the formwork to burst.

The second generation: Plasticizers 2.0: This type of plasticizer can significantly lessen the water-to-cement ratio of around 25%. Polysulfonates like naphthalene and melamine offer same type of working mechanism to the first generation of plasticizers, producing an electrical dispersing albeit of superior intensity.

These polymers conform to the cement particles, charging them negatively to form repulsion among related particles, allowing water to flow and hydrate the mix in an efficient manner.

This similar repulsion activity also activates major air occlusion, raising the workability of the mix but at the same time developing pockets of air that reduces its resistance and settle its structural integrity.

This type of polymer may also put other challenges, since it provides a very narrow window of ‘workability’: as soon as the cement is hydrated, it is likely to develop a crust-like byproduct that makes application complicated.

Super-plasticizers: the third generation - Super-plasticizers stands for the additives which bring huge benefits along with a water-to-cement ratio curtailment of around 40%.

Polycarboxylates alias High Range Water Reducers (HRWR) function on the base of sterical in spite of electrostatic repulsion. A major steric effect is steric hindrance for which a chemical reaction can’t occur. In this case it stops cement particles from agglomerating.

Polycarboxylates stands for complex co-polymers which are applied to satisfy several functions, and comprise of a negatively charged ‘backbone’ molecule with polymeric side chains.

Most of these additives can be amalgamated jointly, and blended with other types like air-entraining, accelerating and retarding additives

Types of plasticizers commonly used and their benefits



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Published By
Rajib Dey
www.constructioncost.co
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Thursday, February 7, 2019

Details about various sections of bridge

All the major elements are arranged within three main bridge areas – Foundation (that retains the shallow or deep base of the bridge and transmits it’s load to the bearing strata, it comprises of foundations underneath the primary span of the bridge and the abutments underneath starting points of the bridge), Substructure (piers, abutments, spandrels, caps, bearings, and other elements that retains the top part of construction) and Superstructure (all the segments of the bridge which are assembled on top of the supporting substructure system, it comprises of various components like decking, girders, slab, and everything arranged over the main deck like posts, steel truss system, bridge girder, cable-stayed system, cable suspended systems and more).

The followings are the major elements of the modern bridges:

Abutment – Endpoints of the bridge. They are reinforced to facilitate withstanding extreme lateral pressures.

Pile (also called as beam, footing, and pier) – It stands for reinforced concrete post that is pushed into the ground to function as the leg or support for the bridge. The extent among piles is worked out to provide support to the rest of the structure that will be placed on top of them.

Cap – Cap is located on top of the pile beam that gives extra support and distributes the load to the piles underneath. The amalgamation of Pile and Cap elements is known as Bent.

Girder or Span – It is one of the major components of the bridge that attaches all the Piles beams. It involves several simple spans, a single continuous span that is supported with numerous beams, cantilever spans and cantilever spans with the suspended span among them. They are normally formed with metal or reinforced concrete as well as in the form of haunches girded be bear more load. Girder sections are usually not formed with a simple block of material but built up with truss network (or Orthotropic beams) that enhance their resistance capacity against load. Girders are also utilized as a part of rigid frame network where they are totally attached with frame legs (that may appear as inclined or in V shape).

Superstructure truss network – Truss network that provides supports to travel surface is built with three basic ways – Deck truss where traffic passes on top of truss network, Pony truss where truss network passes among two parallel walls of trusses, and via truss that includes extra cross-braced truss network over and below the traffic.

Deck beam – Simple continuous decks are created with metal or reinforced concrete. They comprise of sub-components like approach slab (attaches main bridge decking with the ground on both sides of the bridge), expansion joint, drainage scupper, curb, running surface, footpath.

Barriers – These are the sides of the bridge decks normally contain extra barrier components like railings, handrails and ground fixtures.

Arch – Arches on the bridges are differentiated with the number of hinges they contain (normally among zero or three) which ascertain the volume of stress and load they can bear securely, and the type of material they are built up (solid material, truss system). Arches underneath the bridge are known as spandrel-braced (cantilever) or Trussed deck arch.

Spandrel – Spandrels belong to the almost triangular space among the main pillar of the bridge and decking. Stone bridges employ filled “closed” spandrels deck arches, whereas the modern bridges are constructed with metal having open spandrel deck arch configurations.

Truss – Framework is created by attaching triangles and other forms that disperse load and stress forces across its whole structure. They are generally segregated into various categories like simple truss (King and Queen posts), covered bridge truss (multiple kingpost truss, Howe truss, long truss, Burr arch truss, town lattice truss, Haupt, Smith, Partridge and Child truss), Pratt truss (and it’s many variations), Whipple truss, Warren truss variations, Howe truss, Lenticular truss, Fink truss, multiple Cantilever truss variations, and suspension truss arches.

Details about various sections of bridge

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Published By
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www.constructioncost.co
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Wednesday, February 6, 2019

Some nice design ideas for the boundaries & fences of your home

Given below, the details of some nice design ideas for boundaries and fences which can be used to safeguard and decorate your home.

Asymmetric geometry: If the home is designed with geometric components like straight lines, cubes or angles then a fence containing an asymmetric pattern can provide a dazzling and balanced appearance. Apply a neutral color so that it merges with the rest of the home.

Wood slats: Wood always offers a warm and comfortable look, and it never comes out of style. It is compatible with almost any design theme and includes a attractive natural component to the boundary.

Rustic wood finish: Unpolished wood in a metal frame provides a elegant appearance for a fence in a garden area since it provides a appealing rustic vibe to the space.

Iron with nature: Wrought iron is a perfect fit for a fence and is often integrated with brick for a classic appearance. However, it is possible to produce creating designs with it, similar to this nature-inspired tree pattern that delivers a modern component to the brick boundary wall.

Brick boundary: Because of the roughness of wood, it becomes a popular material for a boundary wall. Apart from including a warm feel to the exterior, it also provides texture, adding a classic appearance to the home.

Resistant WPC: Wood Plastic Composite or WPC is a strong and weather-proof option that can be applied for the fence. It is made of 60% recycled wood, 30% recycled plastic and 10% fire retardant material. As it looks like wood, it’s pretty too.

Wood, concrete, stone and tile: Modern fences employ a combination of materials to produce a spectacular effect. Under this system, the main fence is formed with natural stone on which the concretes planters are set at three different levels to accommodate space for a lovely garden.

Furthermore, with the use of redwood slats and grey stone cladding, the wall turns to be attractive.

To get more details, go through the following link www.homify.in

Some nice design ideas for the boundaries & fences of your home

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Published By
Rajib Dey
www.constructioncost.co
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