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Monday, November 20, 2017

Some useful processes to resist corrosion in steel reinforcement

In order to resist damage and failure of concrete structures, steel reinforcement Corrosion control methods are undertaken. Near about forty percentage of collapsing of concrete structures occur due to corrosion of inner steel reinforcement.

There are various reasons for the corrosion of steel reinforcement which range from the quality of concrete, atmosphere, and quality of construction practices.

Initially, it is required to arrange superior quality of concrete via good construction practices to manage corrosion in rebar. To manage rebar corrosion, the focus should be given on various factors like the quality of concrete materials, mixing, placing and compaction methods and good workmanship.
Quality control in concrete construction minimizes the scopes of corrosion. By applying the following methods, the corrosion of reinforcement bar can be controlled efficiently.
Steel reinforcement corrosion control processes :-
• Cement-Polymer Composite Coated Rebars (CPCC)
• Fusion Bonded Epoxy Coated Rebars (FBEC)
• Corrosion Resistant Steel Deformed Rebars (CRSD)
1.Cement-Polymer Composite Coated Rebars (CPCC): Cement polymer coat rebar implanted in concrete are encircled through an alkaline medium. A cement base coating is very effective in controlling reinforcement corrosion. Two coats of cement polymer are used on rebar like first Primer coat and a sealer coat.
Products contained in Cement Polymer Composite Coated rebar are:
• De-rusting Solution
• Alkaline Powder
• Phosphating Jelly
• Inhibitor Solution
• Sealing Solution
2. Fusion Bonded Epoxy Coated Rebars (FBEC): Fusion bond epoxy coat rebar is formed with 100% solid delicately grounded fuse powder particles. These particles are dissolved through heating to develop a permanent adherent film. There is not any passivating primer film contained in FBEC rebars. It produces a medium of weakness in the path of an intimate bond among rebar and alkaline concrete.
Epoxy provides the coating to the rebar with the following :-
• Melts
• Flows
• Gels
• Cures
• Cools
• Adheres to coating
3. Corrosion Resistant Steel Deformed Rebars (CRSD): Under this method, an initial layer of protective oxide or rust is created to resist the corrosion. On general rust on normal rebars, the CRSD rust is passive, persistent and self-renewing. The preventive oxide is fine texture, tightly adherent and a barrier to moisture, oxygen, carbon dioxide, Sulphur dioxide. The chloride provides protection against corrosion.
It is suggested to employ corrosion resistance Steel Deformed Rebars to resist corrosion of concrete structures, damage, and collapsing of concrete structures.
Article Source :
Some useful processes to resist corrosion in steel reinforcement

Published By
Rajib Dey

Saturday, November 18, 2017

How to design reinforced & unreinforced concrete and masonry gravity retaining walls as per Euro & BS codes

MasterKey Retaining Walls Design provides the most extensive program that can be used for creating the design of both reinforced and unreinforced concrete and masonry gravity retaining walls as per Eurocode 7, BS 8002, BS 8110, CP2 IS 325 and BS 5628 Part1 and Part2. Highways design by adhering to BD 30/87 & BD37/01 is also comprised.

The users can easily use MasterKey Retaining Walls with a short learning curve.

With it’s collaborative nature, it is possible to instantly view the effects of inserting loads, piers, ties and props, rectifying reinforcement as well as the wall geometry or soil properties. MasterKey Retaining Walls offers you complete control over the design method, allowing you to improve the efficiency of the wall.
• Design Codes: British, Irish & Eurocode design
• Concrete retaining wall design
• Masonry retaining wall design
• Cavity, bed-joint and pocket reinforcement in masonry walls
• Design to Eurocode 7, BS 8002 or CP2
• Design to Highways BD 30/87 & BD 37/01
• Stiffened and unstiffened walls including buttressed and counterfort walls
• Layered soil modelling
• Water table and horizontal surge force
• Cohesive and granular soils
• Sloped or stepped front and back faces
• Upstand above top of soil
• At rest earth pressure
• Multiple props, ties and spring supports
• Line loads on wall, base and embankment
• Partial distributed surcharges
• Exports DXF details
• Exports details to MasterRC for AutoCAD
• Schedules using the MasterRC Scheduler
In order to download a full functioning 30-days trial version, click on the following link

Published By
Rajib Dey

Friday, November 17, 2017

Learn the process to Seal or Repair Cracks in Concrete Floors & Walls

This article sheds light on how to seal and repair cracks in concrete floors, poured concrete slabs, foundations, walls, or other masonry.

Information is provided for all the existing processes which are useful to seal control joints or cracks taking place in those building surfaces.

Information is also given for the properties, general process, and benefits and disadvantages of each process like control joint inserts, masonry caulks, radon crack sealants, semi rigid epoxy resin crack fillers, special poly urea caulks designed as a joint filler - polyurethane foam injection to seal cracks, grouts along with portland cement, latex-modified, epoxy, modified epoxy-supported, and furan grouts or other products applied to fill or seal cracks in concrete or other masonry surfaces & structures.
Discussion is made on how to select among and utilize the alternative procedures for repairing or sealing cracks in masonry surfaces like poured concrete floor slabs, concrete foundation walls, or brick or masonry block foundation walls. Application of epoxy sealants, polyurethane foam sealants, and hydraulic cement crack repair sealants.
This article series also explains how to identify and analyze different types of foundation failure or damage, like foundation cracks, masonry foundation crack patterns, and moving, leaning, bulging, or bowing building foundation walls.
Types of foundation cracks, crack patterns, variations in the meaning of cracks in several foundation materials, site conditions, building history, and other evidence of building movement and damage are explained to facilitate identifying foundation defects and to allow the inspector for isolating cosmetic or low-risk conditions from those expected to be crucial and potentially costly to repair.
The focus is also given on a list of materials utilized to fill poured concrete slab control joints. Also learn how to seal a cracked masonry foundation wall or floor slab. Typical concrete crack groundwork for sealant with an epoxy product.
Application of Polyurea as a control joint filler or crack sealant in concrete slabs (Polyurethane Foam Injection Method). Utilization of Epoxy-supported Grouts as a control joint or crack filler in concrete slabs or walls. Complete lists of the Types of Tile Grouts, their Bonding Agents and other Properties. As well as Concrete expansion joint sealant products, epoxies, caulks.
Utilization of Hydraulic Cement for Repairs in Concrete Slabs, Foundations, or Masonry Block/Brick Walls.
To get more details, go through the following link
Learn the process to Seal or Repair Cracks in Concrete Floors & Walls
Published By
Rajib Dey

Thursday, November 16, 2017

Brief overview of various building elements necessary for reinforced concrete structure

1st Floor: It belongs to the floor that contains 1 storey height over ground.

Basement Floor: The floor that is located at basement of the building. It is also known as cellar. The basement floor is situated either entirely or partly underneath the ground floor. A basement is utilized closely in the similar way like a supplementary above-ground floor of a house or other building.

The application of basements mainly based on several factors associated with a specific geographical area like climate, soil, seismic activity, building technology, and real estate economics.
The concrete floor in most basements is not included in the foundation structurally except the basement walls. With the surge of warm air, basements are normally cooler compared with the remaining part of the house. In summer, it makes basements damp, because of the greater relative humidity.
Basement Wall: The wall that encircles the basement floor is known as the basement wall and it considered as a vital portion of the foundation structurally. The basement walls stands for shear walls which have the ability to withstand the lateral loads also. Besides, these walls are considered as highly non-porous and water-defiant.
Column Bracket: Column Bracket is over hanged from the column and it is useful for hanging or affixing lamps, bulbs or other accessories to it similar to road signs.
Column Capital: Column capital belongs to an architectural element that is utilized for aesthetic purposes to develop the uppermost member of a column.
Drop Panels: The objective of drop panels is to solidify the slab around the column in flat slabs to get rid of punching shear. As flat slabs do not contain stirrups, shear is defended by solidifying the slab around the column to raise the concrete in shear. Beams are also applied, but normally drop panels are most effective to get rid of conflicts with the electro-mechanical works of the structure.
Exterior Columns: These are the columns which provide support to the primary structure of the building. Normally in frame structures, the exterior columns are very crucial and sustain the load of the building as well as withstand environmental factors like wind, rain, and other physical factors.
Flat Plate: These are the slabs to be attached with the columns directly. Flat plate system is mostly recognized by the engineers as it offers huge benefits. The system can curtail the height of the building, offer more flexible spatial planning as there are no beams. It also minimizes the material cost significantly. But the issue is that it can be easily broken and may collapse against punching shear. Because of the comparatively small floor loading and the tight column spacing, flat plate construction is getting popular.
To combat greater loading and larger column spacing, column capitals are necessary, and for even bigger spans to decrease the self-weight, waffle slabs are required.
To get more information, go through the following article
Brief overview of various building elements necessary for reinforced concrete structure

Published By
Rajib Dey

Wednesday, November 15, 2017

Placement of lap in column as per IS Code 13920

This construction video tutorial sheds light on reinforcement lapping zone in column. By going through this video, one can learn how to place lap in exact position in column by adhering to IS code 13920.

A lap is required when two pieces of reinforcing bar (rebar) are overlapped to produce a constant line of rebar. The length of the lap fluctuates according to the concrete strength, the rebar grade, size, and spacing.

The objective of lap is to transmit load from one bar to another bar as well as retain continuity. The positioning of lap is dependent on the bending moment of the column.
Lap length refers to the length of the overlap of bar necessary to securely transmit stress from one bar to another. Lap length varies on the basis of tension and compression zones and mostly relies on grade of concrete and steel. Development length refers to the length of the bar necessary to transmit stress from steel to concrete.
Rebars in column should have been lapped at around 5 feet from the story.
As stated by I.S. 13920 Vertical bars of Columns should be lapped in regular zone (Mid-height ) only and it should be spread out i.e. not surpassing 50% of bar is lapped at one section. Besides, lowest clear vertical distance among lapped bars should be 0.25 times lap length.
To get more details, watch the following video tutorial.

Read more

Published By
Rajib Dey

Tuesday, November 14, 2017

Basic needs of a Building

The planning and construction of a building is undertaken on the basis of the following conditions :-

Strength and Stability – There should be proper arrangement for building to transmit the probable loads securely to the ground through it full lifecycle. Proper safeguard should be taken for designing various types of structural elements like slabs, beams, walls, columns and footing. All the structural components should be free from buckling, overturning and collapsing.

Dimensional Stability - The structural elements become instable due to extreme deformation that may lead to crack in walls, flooring etc. All the structural elements should have been designed in such a manner so that the allowable values mentioned in the codes should remain within limit.
Resilience to Dampness - Dampness in a building is a vital concern as it may endanger the life of the building. To get rid of dampness, proper precaution should be taken in planning and in the construction of the building.
Resistance to Fire: To maintain fire resistance capacity, the building should abide by the following basic needs mentioned in the codes:
• the structure should not be inflammable easily.
• there should be perfect building orientation to resist the scattering of fire quickly.
• to escape from fire, there should be ways of smooth access to depart from building rapidly.
Heat Insulation- A building should be properly oriented and designed to protect inside area from heat.
Sound Insulation – The planning for building should be done in such a manner to protect from outdoor and indoor noises.
Safeguard from Termite – Proper protection should be taken for buildings against termite.
Stability - Each and every element of the building should be stable enough.
Security against Burglary - This is the basic requirement that the owner of the building look forward to.
Lighting and Ventilation- To maintain a healthful life, there should sufficient natural light and ventilations.
Diffused light and good cross ventilation should be retained within the building.
Comforts and Amenities – Different types of units in the building should be perfectly grouped and incorporated ensuring the comfort and amenities of the user.
Basic needs of a Building

Published By
Rajib Dey

Monday, November 13, 2017

Various types of masonry Mortar

Mortar is extended in among the masonry, grouts, and stuffs the cavities of the masonry units. Mortar belongs to the material that is visible among the bricks. Mortar allows the masonry units to remain jointly. Mortar is very vital in masonry construction. It is always recommended to apply the proper mortar or grout.

The process is complicated to find out the exact mixture for the mortar or grout for maintaining proper strength. The mortar or grout should contain the perfect strength to get rid of over bearing issue (load bearing in this case). Besides, the mixture that retains the masonry sections together should not be considerably stronger that what the masonry units are, because it can transform the load bearing to gain extreme amount of stress.

If the mortar’s mixture is not provided properly it can lead to weighing over the masonry units themselves and results in damaging the structure with cracking and/or spakling.
The categorization is done on the basis of ASTM C 270 (Standard Specification for Mortar for Unit Masonry). Given below, various categories of mortar.
Mortar-Type M: Mortar (Type M) contains a minimum 2500 psi and suitable for areas to withstand a considerable amount of load bearing, wind forces, earthquakes, and etc. This specific type of mortar is normally applied with stone. If the Mortar is formed with any material that contains less strength, it may collapse the structure and its job positioning prematurely.
Application - This type of mortar is normally applied with stone as it closely simulates the strength of stone, it will not collapse prior to the stone itself collapses.
Mortar (Type S): This type of mortar contains a minimum of 1800 psi. It contains medium strength, and defined as (Type S). It is mostly utilized for outside structures like a patio as well as exterior walls which are assessed below grade as it is more durable as compared to (type N). Therefore, it is best suited to perform with mildly withstanding soil pressures below grade.
Applications - Below grade having normal to moderate loading. In some areas where the masonry touches the ground, like paving or shallow retaining walls.
Mortar (Type N) for general purposes: Mortar (Type N) is mostly recognized mortar. This type of mortar is utilized when there exist no other special circumstances which need a specialty for the load bearing of a structure. It has medium strength (minimum 750 psi) and is suitable for reinforced interior and above-grade exterior load-bearing walls. It is perfect for semi-soft stone or masonry as it will bend in excess of a high-strength mortar to resist prevents cracking of the masonry units.
Mortar (Type O): Mortar (Type O) refers to a mortar that contains a low strength (a minimum of 350 psi). This type of mortar is useful for interior usages where non-load bearing exist. It is frequently applied to patch mortar where the wall has strong structure. Type O mortar is occasionally applied with masonry units having a low compressive strength (i.e. sandstone or brownstone) to allow more flexibility for resisting cracks in the units.
Applications: Interior non-load-bearing areas with very restricted exterior use because of its low structural capacity and not suitable for the areas prone to high winds. Type O Mortar mix is perfect when repointing because of its stability. It is applied in above grade, non-load bearing situations preferably in interior environments.
Mortar (Type K): The (Type K) Mortar is not listed under the ASTM C 270 anymore, although it is still applicable to projects which have a pre-historic preservation need. This type of mortar will not produce any damage to a fragile structure, nor to any fragile stones as it contains the lowest compressive strength of any mortar.
Applications : Mortar (Type K) is useful for safeguarding pre-historic structures, which needs the use of a low strength mortar to get rid of any damage. Type K is not recommended for load bearing.
Various types of masonry Mortar

Published By
Rajib Dey

Friday, November 10, 2017

How batching of concrete is done

Concrete is a multipurpose, long-lasting, eco-friendly, and inexpensive material as well as globally recognized construction material. To produce superior quality concrete, the components of concrete should be calculated properly and perfectly. Once mix design is set, the initial task should be batching materials.

Batching of concrete stands for the method of estimating and mixing necessary concrete ingredients both with weight or volume according to the mix design and implanting them into a mixture to form a consistent quality of concrete.

By perfectly computing all the material applied in the concrete formation, it becomes possible to maintain consistency of proportions in all consequent batches.
Why Batching of Concrete is Important?
Usually, following three types of batching are undertaken for concrete components:
01. Random Volumetric Batching: Batching devoid of any control on the size and shapes of applied containers leads to big errors and deviations like utilizing “ghamellas” i.e. – by tallying numbers of ghamellas. This method is totally unscientific, unrefined and should not be recommended even for a small project.
02. Volume Batching of Concrete: Volume batching of concrete is accomplished with the use of measurement boxes, locally named “farmas or gauge boxes”. Concrete components like aggregates ( Kapachi +Sand) and cement is calculated with farmas or gauge boxes and proper precaution should be maintained to ensure that the farmas or gauge boxes are filled excessively. To calculate the quantity of water, the water meter should be utilized when batching or use cans of water contain fixed volume.
03. Weigh Batching of Concrete: Weigh batching of concrete is accomplished with the use of a weigh batch or the weighing system on the batching plant. On big projects, automatic batching plants are set up to facilitate optimizing quality and uniformity.
Water is very vital material and therefore, maximum water should be used for batching. If the quantity of water is less, the functionality of concrete will be hampered whereas surplus water will minimize the strength of concrete. Water should be computed perfectly in litres.
The selection of batching method is based on the size of job, production rate and standards of batching performance.
Usually batching is performed with volume. Precision in batching is very crucial. It is better to perform weigh batching instead of volume batching. Volume batching is mostly effective where weigh batching is not possible. It is always recommended to incur additional cost for it, because in long term, it saves huge costs.
Note: The quantity of cement should also be calculated by maintaining the precision of ± 2 percent and the quantity of aggregates, admixtures and water should be calculated with a precision of ± 3 percent.
Article Source:
How batching of concrete is done

Published By
Rajib Dey

Thursday, November 9, 2017

A position is vacant for Quantity Surveyor / Estimator

Introduction: A leading medium size business situated in Benoni and engaged with the manufacturing, and installation of Prefabricated Modular Buildings, together with structures and related services, like basic reticulation and civils, is inviting application for a young +- 30 years old Quantity Surveyor who possesses a degree of BSc or BTech (QS).

The candidate should contain at least 5 years experience and onsite experience with contracts with regard to residential housing / Offices / Warehouse construction.

Objective of the job:
• The candidate has to price all the submitted tenders which should contain the following:
• Rate all project costs along with P&Gs, project cash flows, project programmes.
• The candidate should also take responsibility to monitor to commercial prospects of alloted projects and carry out closeout reports.
Duties and liabilities:
• Costings and budgets formation for the allotted projects.
• Tender and contract documents formation together with the bills of materials for procurement.
• Advocating on the procurement policy.
• Accomplishing monthly valuations of work progress, along with forecasting of final costs.
• Estimate, value, submit and negotiate contract variations.
• Control and generate perfect formal reports with reference to the project timelines.
• Recognizing, analysing and developing responses to commercial risks.
• Providing support to general manager with a range of other duties as essential from time to time.
Skill Requirements:
• Technical qualification with a degree in B.Sc (QS) University Degree or B-Tech Degree.
• At least 5 years experience with quantity surveying in South Africa.
• Should contain sound practical organisation skills, planning of resources and programme scheduling.
• Should be capable of providing both summarised and detailed reports on current activities.
• Good knowledge in computer and have the capability to apply Microsoft Office and Microsoft Projects.
• Comprehensible experience in arranging tenders respecting construction.
• Personal Attributes:
• Motivated and determined individual.
• Good speaking power in English.
• Eagerness to travel.
• Good team player and effective communicator.
• Negotiable based on experience
To apply online, go through the following link
A position is vacant for Quantity Surveyor / Estimator

Published By
Rajib Dey

Wednesday, November 8, 2017

Guidelines for site layout or job layout at construction site

Site layout refers to the plan of the construction site. It provides the area as well as the proper position for arranging the necessary resources in the construction work.

It specifies the place for offices, godowns, workshops, accommodation etc. It also illustrates the present relationship of the site with its surrounding with regards to communication, approaches and existing facilities.

Given below the importance of a systematic and technically organized site layout :-
1. Obtain an uninterrupted supply of materials in adequate amount.
2. Get a smooth access to material and test out its wastage and degradation.
3. Reduce the number of plants as well as the movement of heavy equipment.
4. Prevent confusion and minimize accidents.
5. Keep a systematic viewpoint for easy inspection of the materials.
The layout that fulfills most of these conditions enhances efficiency along with productivity. Such a layout is recognized as optimum layout. The site layout is mainly based on the following factors.
1. Position of the site, 2. Arrangement of space, 3. Access to the site, 4. Material volume, 5. Type of applicable equipment, 6. Ground conditions.
Fundamentals of jobs layout: The following fundamentals should be maintained for job layout.
1. If possible, there should be two openings in the site, one for entry and the other for exist to allow flow of traffic. For the existence of only one gate, then it is preferred to arrange a cross-over near the gate.
2. The general office should be situated adjacent to the main gate to stay away from confusion at construction site.
3. The godown should be situated just at the back of the general office so that the delivery of the material is accumulated in it. It also allows a tighter supervision of the stores.
4. Temporary roads should have been built up around the operation area. It makes the flow of material as well movement of equipment better. In reality, if such roads are essential to be built up in the project, it is suggested to build them initially in order that these can be utilized throughout the construction accurately.
5. The workshops for joiner, fitter, electrician etc should be determined and placed by balancing the easy and short access routes..
6. Staff accommodation should be far from noise. It should be centralized in one area to facilitate communication and trim down the cost of facilities and services.
7. The existing services should be used as far as possible.
Guidelines for site layout or job layout at construction site

Published By
Rajib Dey

Tuesday, November 7, 2017

Shaft3D – A powerful software for foundation design and analysis

Shaft3D software is created for simplifying the pile design process specifically for the drilled shafts or caisson type foundations. The software will allow you to perform multi tasking like shaft axial capacity analysis, lateral analysis and concrete design etc.

With Shaft3D, it is possible to design caisson foundations for windmills, transmission lines, utility lines or any other structure requiring drilled pier foundations quickly.

Shaft3D can enhance your productivity considerably through its windows-based, easy-to-learn graphical interface and its capacity to offer a complete solution for different types of analyses.
Given below, some useful features of the software :-
• International Design Codes: Compatible with various concrete design codes to finish your global projects efficiently.
• User Defined Parameters: There are various design options like shaft boundary conditions, choice of safety factors in end bearing, skin friction and pullout, choice of axial capacity methods and lot of others to fulfill numerous project specifications.
• Graphical Input of Soil Profile: Facilitates input of unrestricted number of soil layers, each with various unique set of soil properties graphically permitting you to visualize your soil profile.
• Soil Property Values: Offers a series of values of soil properties like cohesion, angle of internal friction with selection of the soil type authorizing you to complete a preliminary design devoid of detailed soil report.
• Load Cases and Combinations: Produces generally used load cases and combinations for shaft design that saves design time considerably.
• Multiple Analyses: Accomplishes axial capacity analysis, lateral analysis and concrete design in one combined surrounding.
• Axial Capacity Methods: Facilitates to choose from several axial capacity methods so that it is possible to fulfill the need of your company or client.
• Lateral Analysis: Accomplish lateral analysis with finite element analysis demonstrating vital information like deflections, shears, bending moments along the length of the shaft allowing you to explore with different “what-if” scenarios.
• Concrete Design: Execute concrete capacity design for axial loads and biaxial bending that offers you a complete geotechnical and structural solution.
• Rebar Layouts: Generates several rebar layouts with customization options.
• Material Quantities: Produces material quantities to perform precise cost estimates for your customers each time at each phase of the project.
• Detailed Design Sketches: Creates a detailed design sketch with plan, elevation and section to sum up the completed design efficiently.
• Multiple Reporting Options: Produces various types of customizable reports to utilize them for your internal or client requirements.
To know the additional features, go through the following link
Shaft3D – A powerful software for foundation design and analysis

Published By
Rajib Dey

Monday, November 6, 2017

Details of Foundation in Construction?

A foundation alias ground sill is the low part or sub-structure of an architectural structure that is artificially constructed on the soil to transmit loads from the structure to the ground securely. Foundation of a structure is built up underneath the ground level with the purpose of making the lateral strength of the structure better. The solid ground on which the foundation is supported is known as the Foundation Bed.

On the basis of the condition and bearing ability of soil and nomenclature of structure, the foundation is categorized as shallow foundation and deep foundation.

If the depth of the foundation is under or similar to its width or if the foundation is built up at proper shallow depth, it is called shallow foundation. A shallow foundation delivers the load to a stratum found in a shallow depth. Shallow foundations are generally found in building up low rise structures.
If the depth of the foundation surpasses its width or if the foundation is developed at considerably large depth, it is call deep foundation. The deep foundation transmits the load to a wider depth under the ground surface. Deep foundation is intended for high rise or multi-storey structures.
1) Shallow Foundations
i. Spread footing or open trench foundations
ii. Grillage foundations
iii. Mat or Raft foundations
iv. Stepped foundations
v. Inverted arch foundations
vi. a) Wall Footing
vii. b) Reinforced cement concrete footing
viii. c) Combined footing
ix. d) Eccentrically loaded footing
Deep Foundations - i. Pile foundations, ii. Well foundations, iii. Caisson foundations
To erect a foundation, trenches are excavated thicker into the soil unless a solid stratum is attained. To make the base foundation, concrete is poured into this trench. These trenches are combined with reinforcement cage to raise the foundation stability.
The estimated steel rods which are provided outwards perform as the bones and should be attached with the substructure above. Once the foundation work is completed successfully, the structure of the building is started.
The construction of the foundation can be done with concrete, steel, stones, bricks etc. The material and the type of foundation selected for the desired structure depends on the design loads and the type of underlying soil.
The design of the foundation must incorporate different effects of construction on the environment. For example, the digging and piling works done for deep foundation may result in adverse disturbance to the nearby soil and structural foundation. These can sometimes cause the settlement issues of the nearby structure. The objective of developing of a foundation is to withstand the attack of injurious substances from outside.
The foundation for each structure is made by adhering to the following guidelines:-
1. The underlying soil beneath the foundation structure does not experience shear failure
2. The settlement should be occurred throughout the first service load or should have been within the limit
3. Acceptable bearing pressure should be described as the pressure the soil can resist devoid of any failure.
Objects of Foundation:
1. To allocate the load of structure on wider area to maintain the intensity of load under the safe bearing capacity of the underlying soil.
2. To allocate the load uniformly on the underlying soil to avoid any unequal settlement of foundation.
3. To arrange leveled and hard surface for the super-structure to be constructed over it.
4. To raise the strength of the structure completely against sliding, overturning or other distressing forces like wind, rain, earthquake etc.
For more information, go through the following article
Details of Foundation in Construction
Published By
Rajib Dey

Saturday, November 4, 2017

Brief overview of workability of concrete

The strength & longevity as well as the cost of labor and look of the finished product is greatly impacted by the workability of concrete. The concrete can provide better functionality, if it is easily positioned and compacted consistently devoid of bleeding or Segregation.

The concrete that is not in good working condition should be supported with extra work and endeavor for being compacted in position, also honeycombs &/or pockets are also found in finished concrete.

Definition of Workability: Concrete workability defines how smoothly freshly mixed concrete is amalgamated, arranged, compacted and finished by keeping the conformity as it is. Workability refers to a property that directly affects strength, quality, appearance, as well as the cost of labor for placement and finishing operations.
The workability is impacted with the following factors :
1. Water content in the concrete mix
2. Amount of cement & its Properties
3. Aggregate Grading (Size Distribution)
4. Nature of Aggregate Particles (Shape, Surface Texture, Porosity etc.)
5. Temperature of the concrete mix
6. Humidity of the environment
7. Mode of compaction
8. Method of placement of concrete
9. Method of transmission of concrete
The workability of concrete can be improved in following ways :-
1. Raise the proportion of water/cement
2. Raise size of aggregate
3. Apply well-rounded and smooth aggregate rather than asymmetrical shape
4. Rise the mixing time
5. Enhance the mixing temperature
6. Employ non-porous and saturated aggregate
7. Include air-entraining mixtures
The most recognized method for measuring the workability of concrete is Slump Test.
Brief overview of workability of concrete

Published By
Rajib Dey

Friday, November 3, 2017

SSC Junior Engineer (Civil, Mechanical, Electrical and Quantity Surveying & Contract) Recruitment 2017

Staff Selection Commission is going to arrange an open competitive Computer Based Examination for appointing Junior Engineers Group-„B‟ (Non-Gazetted) posts, in Level-6 (Rs.35400-112400/-) of pay matrix of 7th CPC w.e.f. 5th January 2018 to 08th January 2018.

The last date of submitting application is 17-11-2017.

The written examination through computer will be held on 05-01-2018 to 08-01-2018.
Detail of Posts: Only the male candidates are allowed to apply for the posts of Junior Engineers in Director General. Border
Roads Organisation (BRO), Ministry of Defence.
Reservation: Reservation for SC/ ST/ OBC/ ExS/ PH etc. categories is available as stated by extant Govt. Orders and as announced by the departments reporting vacancies.
The posts are recognized as appropriate for the persons who are suffering from disabilities of forty percent 40%) and above of One Arm (OA), One Leg (OL), Hearing Handicapped (HH) as stated by the Ministry of Social Justice and Empowerment.
To get more information on the vacancies, go through the following link Apply Now

Published By
Rajib Dey

Thursday, November 2, 2017

Some useful tips for making inspection of reinforcement in jobsite

Though the inspection of reinforcement involves lots of complexities and huge cost, but the problem should be properly resolved by appointing a standard consulting firm for accomplishing the inspection work.

The first step should be checking drawing. One must have adequate knowledge for analyzing a rebar drawing. The field engineers should have proper knowledge & capability to communicate with it in the jobsite.

To become an efficient rebar checker, practice for reading drawings on a regular basis. For this purpose one should gather proper knowledge with the steel rebar binding process. Given below, some useful tricks provided by some top peers who have lots of experience in this field :-

It is suggested to carry a measuring tape with yourself all the times for the purpose of examining the spacing and the splice or development length.

One should have clear conception on physical features of the construction component i.e. if some type of drainage pipe or electrical conduit should be set up or water stopper should be substituted or any other pipes / implanted item should be arranged.

Initially, the diameter of rebar should be examined properly through a vernier caliper. The other important things which should be examined thoroughly are rebar spacing, rebar development length, lap / splice length, alignment, no sag or buckling present in the bars, the couplers should be perfectly set and tightened, bars should be perfectly fixed, there should not be any rust on the bars, check for proper clear cover, no of bars should be computed properly and be similar with the drawings and should not be under or over 2 bars which are arranged there.

Always take suggestions from the contractor’s foreman or site engineer for the placement of the bars.
One should have sound knowledge with the steel quality tests like tensile strength check or torsion failure strength or coupler tension strength check etc. Make sure that the applied steel is taken from the verified lot and must not be a failed quality.
Though proper execution of design becomes very complicated because of inconsiderate field conditions and difficultly in installation / fixing of rebars, but always ensure the design of reinforcement is completely perfect as improper design can lead to failure of a building if fully neglected / violated.
Always keep in mind that the orientation of bars like main rebars should be under the distribution or temperature rebars. It can be verified from the drawings delivered to you.
Some useful tips for making inspection of reinforcement in jobsite

Published By
Rajib Dey