Search

Manufacturing in RCC Construction – Prefabricated rebars

By
Priyanka Gupta

Three decades back, a construction site was a place where all building materials were brought in fabricated or mended as per need and then used. For example cement, sand, stonechips and water was assembled at construction site; mixed as per design and used. Brick kilns were the only manufacturing/ prefabrication done in advance for construction. Storing of inventory at construction sites wasvery much prevalent.

The concept of factories and automobile industry like ‘lean engineering’, ‘just in time delivery’ and prefabrication have changed the very picture of construction site. But till early 2000 prefabrication in construction rebars was only in concept. Around 2010 prefabrication of TMT rebars started in India and now it has become indispensable for both large as well as small scale project.

Continue Reading »

Filed under Steelworks | 1 Comment

Comparison Between CPCC, FBEC & CRSD

By
Priyanka Gupta

Before doing the comparison study lets know what these terms mean.
CPCC – Cement-Polymer Composite Coated Rebars
FBEC – Fusion Bonded Epoxy Coated Rebars
CRSD – Corrosion Resistant Steel Deformed Rebars

1.0 Corrosion Control of Reinforcement bars (Rebars)
40% of failure of structures is on account of corrosion of embedded steel reinforcement in concrete. Therefore corrosion control of steel reinforcement is a subject of paramount importance.First and foremost for corrosion control is the good quality of concrete through good construction practices.

Fig. 1 Different types of crack formation

Fig. 2 Crack formed due to bursting pressure on account of rusting of reinforcements

Continue Reading »

Rust / Corrosion of Reinforcement Bars – A challenge to overcome

By
Mr.Sourav Dutta
Manager (Civil)
Tata Steel Ltd

Rusting/Corrosion are mainly caused due to:
1. Prolonged exposure of rebar to atmosphere/rainfall without any precaution.
2. Aggressive/saline/toxic environment.

RUST is caused by the reaction of air (O2) and moisture (H2O), and it is a common and natural phenomenon for most steel products. IT SHALL NEVER BE CAUSE OF CONCERN/REJECTION OF REBAR, AS PER BIS.

Fig  Guideline of BIS1786-2008
Fig : Guideline of BIS1786-2008

Continue Reading »

Problems of using High Grade Steel in Constructions

Presented by:
1) Prof.M.V.Kuriakose B.Tech(Ed), M.I.E. (Retd.Principal, Govt.Polytechnic, Perinthalmanna)
2) Mr.Jismon Issac B.E (Mech) A.I.E, MBA

[Prof.M.V .Kuriakose is having around 35 years of expertise in Structural Engineering and Designing. He is an active member of Lensfed.]

[Mr.Jismon Issac has 13 years of experience in the manufacturing & Quality testing of Construction Steel bars especially High grade TMT steel bars]

Now days some contractors report a tendency among few design Engineers that they specify grade Fe-500 or higher steel in residential buildings, citing its high strength. If they design buildings considering the use of Fe 500 steel in construction, it could help reduce the volume of steel used and reduce the column size.

The rosy part aside, Fe 500 grade steel could pose quite a few site specific issues during construction, especially for small builders. Considering the reported failures and problems with grade Fe-500 or higher, it is advisable to use Fe 415 in residential and commercial buildings and Fe500 could be used only when the entire design is made according to that grade. This is explained below;

Continue Reading »

Should design life be the same as return period for design conditions?

Design life means the minimum duration a structure is expected to last. The longer is the design life; the higher is the cost of a project. Therefore, in choosing the design life for a structure, engineers should consider the design life which generates a economical project without sacrificing the required function.

In selection of return period of certain design conditions, winds, waves, etc., one should consider the consequences of exceedance. In fact, there are normally no extreme maximum values of these design conditions and its selection is based on the probability of exceedance which is related to return period.

Advertisements

Therefore, design life may not be equal to return period of design conditions because their selections are based on different considerations.

This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.

Filed under Steelworks | 0 Comments