Essential Data for making an estimate

To produce an estimate, various types of data are required. Given below, the details of these data :-

• Drawing i.e. plans, elevations, sections etc.
• Specifications
• Rates

Drawings :

The task for making estimates becomes very complicated, if the drawings are unclear and do not contain full dimensions. Therefore, drawings should be examined thoroughly prior to make an estimate.

Specifications :-

          General Specifications
These provide the nature, quality, class, work and materials in general forms that should be utilized in different parts of work. It allows to develop a general idea of building.

B    Detailed Specifications

These provide the brief description of the different items of works which set the quantities and qualities of materials, their proportions, the process of making workmanship and accomplishment of work.

Rates :-

• The unit rates of every item of work are essential to make the estimate.
• To obtain the unit rates of each item.
• The rates of different materials which are essential parts of construction
• The cost of transport materials.
• The wages of labor, skilled or incompetent masons, carpenters, mazdoor, etc.

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Published by
Rajib Dey
email : rajib_dey@aol.com
website : www.sketchup3dconstruction.com (construction related articles & news)

Brief over view of Plain Cement Concrete (PCC)

P.C.C means plain cement concrete and its also recognized as pre-cast concrete, cement concrete (CC), binding concrete etc. It is formed by blending the cement, aggregate(coarse or fine ),sand and water in proper ratios. PCC is strong in compression but poor in the tension and shear. It's mostly found in foundation work and flooring in building.



Applicable tools for forming PCC:

Generally, the following tools are utilized for developing Plain Cement Concrete.
• Wooden or Steel rammer
• Mixture machine (if any)

Density of PCC:

The density of PCC usually remains at 50mm over Brick Flat Soling (BFS). If BFS is not applied underneath PCC then the thickness should remain at 75¬mm. If the PCC is applied in car park area then the thickness should remain at 75mm over BFS.



Ratios of materials for PCC:

By volume, the ratio of cement, sand and brick chips in foundation or basement is 1:3:6. But, in car park area, the ratio changes to 1:2:4.

Placing and Compaction of PCC:

• Ensure brick soling/sand bed level for PCC is perfect.
• Develop form work for PCC with wooden plank according to stipulated dimensions.
• Cleanse dust or foreign or loose earth from concreting area.
• Wrap the bed of PCC with polythene.
• Produce level pillars of fresh concrete in the area at proper gapping but not in excess of 2m c/c both ways.
• Set the concrete smoothly (don’t through) from one side. Apply the mixed concrete within 45 minutes as soon as the water is mixed.
• The compaction and finishing of PCC should be done with wooden rammer.
• Create the surface of PCC coarsen for joining future work prior to concrete gets solidified.

Curing of PCC:

After PCC is placed for 24 hours, wet the concrete surface by drenching with water or by wrapping with moist gunny bags minimum 7 days.

Examining and Inspection:

• Verify the dimensions of form work of PCC prior to mixing concrete.
• Examine whether polythene sheet is placed over PCC bed.
• Verify the concrete slump (highest slump should have been 75mm)
• Ensure the thickness level of PCC prior to casting by providing steel pegs in concreting area or level pillar of fresh concrete at proper spaces.
• Verify the finish level of PCC by thread fixing with nails in form work.
• Make sure that the concrete is placing smoothly.

Article Source : http://www.acivilengineer.com

Thumb rules for working out quantities in residential buildings

Professional estimators have the ability to measure the quantities of concrete, steel, brickwork, plaster and finishing material depending on the total built-up area of a residential building without noticing the building plans.



Given below, the step-by-step guidelines on how to determine the quantities for a residential building having roughly 1 lakh square foot built-up area.

Concrete- Roughly 4500 cum of concrete will be essential for the structural frame of the building. The thumb rule should be followed as 0.045 cum of concrete per square foot of built-up area. This quantity may rise to some extent for a building with basements as supplementary concrete would go in the raft, retaining walls and to the ramps to the basement.

Rebar- Roughly 540 tons of rebar will be essential. The thumb rule should be followed as 120 kg of rebar per cum of concrete. For highrise buildings, there should be more steel in the colums and the amount of steel per cum of concrete would raise with the height of the building.

Brickwork - Approx 1.3 lakh sq feet of wall would exist in the building with 1 lakh square feet area. Though, the total area of the walls would mostly base on the size of rooms.

Plastering and Paint Area – It is roughly 3 times of the brickwork area . It should be kept in mind that ceiling and staircase plastering are also included.

These numbers are applicable to large residential towers and not intended for small housed and bungalows. It is advised to use these numbers cautiously as they may fluctuate for your specific project.

Article Source : http://india-construction.blogspot.in

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Published by
Rajib Dey
email : rajib_dey@aol.com
website : www.sketchup3dconstruction.com (construction related articles & news)

Details of plinth beam in construction

A plinth alias tie beam stands for a beam that is built up at plinth level among foundation footings and superstructure. The objective of plinth beam is to resist the splitting of column because of load generating from above. It offers extra strength with respect to settlements of the building and earthquake damages. Plinth beam in a frame structure connects all the columns to minimize the length of the columns and thus decreases their effective length and slenderness. Brick or stone masonry is normally constructed underneath the plinth beam.

Plinth beams are generally set up in the situation where the foundations are little deeper and consequently they perform like a bracing or tying element. Plinth beam helps in evading differential settlement in a building because all the load of the wall is borne by the plinth beam below.

In a skeletal system alias a framed structure; plinth beam should constructed initially as soon as the foundation is set up. As the finish floor level of the ground floor is retained higher as compared to the ground level; the empty gap and void is stuffed with a compacted soil to produce a secure surface for the floor to be built up.

Image Source : http://homeinabox.us

The plinth beam is normally expected to be strong enough for bearing the superimposing brick walls efficiently tying the columns and the structure. As per the structural requirement of a building; plinth beam can either be reinforced or non-reinforced.

Plinth beam is very useful in earthquake prone areas. Besides, it is also built up over the natural ground.

Strength of plinth beam concrete shall not be smaller than 20MPa. If concrete is blended by hand, then additional 20% cement should be included to the mixture.

A least depth of plinth beam is 20cm while its width must be similar with the width of final course of the foundation.

It is suggested to arrange two bars having least diameter of 12mm at the bottom of the beam. In the same way, two bars having least diameter of 10mm must be arranged at the top of the plinth beam.

Reinforcement bars should have been safeguarded with 25mm concrete cover. For stirrups, stirrup diameter should be minimum 6mm and a spacing of 15cm is recommended.

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Published by Rajib Dey
Senior Content Editor
www.sketchup3dconstruction (an information hub for civil engineering & sketchup)
Email : globalrajib71@gmail.com

Concrete Design for the Civil PE and Structural SE Exams, 2nd Edition

C. Dale Buckner PhD PE has written an exclusive e-book alias Concrete Design for the Civil PE and Structural SE Exams, Second Edition. The book briefly sheds light on concrete design methods and standards.

This book can be used side by side with PPI’s Civil Engineering Reference Manual (CERM), Structural Depth Reference Manual (CEST), or Structural Engineering Reference Manual (STRM). CERM, CEST, and STRM belong to the fundamental texts for all who are preparing themselves for the civil PE or structural engineering (SE) exams, and each book introduces the basic concepts and most common applications associated with concrete design. It is indispensable that this book should have been utilized with the American Concrete Institute’s Building Code Requirements for Structural Concrete (ACI 318) and Commentary (ACI 318R).



Concrete Design for the Civil PE and Structural SE Exams demonstrates the concrete design and analysis methods very much required by the civil and structural engineering students.  The book’s 12 chapters offer a brief and precise review of concrete theory, code application, design principles, and structural analysis. The 51 example problems present how to employ concepts, codes, and equations, as well as more than 40 figures and tables present crucial support material. A complete nomenclature list describes the industry-standard variables and symbols which are provided in each chapter.



This book comprises of code references to make you acquainted with exam-adopted codes, like ASCE7 and ACI 318. It also contains 35 multiple-choice problems and 2 scenario-based design problems to improve your problem-solving skillfulness. Each problem’s complete solution allows you to verify your solving approach. On exam day, the comprehensive index of this book can be applied to instantly discover vital codes and concepts.

Civil Engineering Book

The includes the following topics
• Columns and Compression Members
• Continuous One-Way Systems
• Design Specifications
• Development of Reinforcement
• Flexural Design of Reinforced Concrete Beams
• Materials
• Pre-stressed Concrete
• Seismic Design of Reinforced Concrete Members
• Serviceability of Reinforced Concrete Beams
• Shear Design of Reinforced Concrete
• Two-Way Slab Systems

Go through the following link to purchase the book online from amazon.
https://www.amazon.com/Concrete-Design-Civil-Structural-Exams/dp/1591264731

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Published by
Rajib Dey
email : rajib_dey@aol.com
website : www.sketchup3dconstruction.com (construction related articles & news)