More than half a million years ago, humans started building tools and shelter out of animal bones, antler, stone and wood. If we are to find out the history of wooden houses it will take us back to the stone age for sure. During 9000 to 5000 BC, the largest structures in the world were the Neolithic longhouses, a long and narrow timber structure housing 20 to 30 people. Such dwelling was built by first farmers in Europe, Central Europe to be exact in connection with the early Neolithic cultures such as the Linear Pottery culture or Cucuteni culture.
The Supreme Court order of demolition of five buildings in Marad, Kerala has come as hot news in media with the people applauding the order as well as a few condemning them. This has not been the first instance of demolition of buildings for illegal construction in coastal lines against the CRZ regulations. Rainbow restaurant, in the banks of Periyar, Aluva also met a similar fate of demolition for illegal construction on CRZ regulations in 2014. Why were these construct to be taken down and what does the coastal regulation zone mean. It has been a question that plagues us.
Wooden structures are lightweight, energy efficient, versatile and sustainable solutions. In Earthquake prone areas wooden structures have the advantage that the wooden framed building won’t break off easily. They are flexible, economical and more versatile compared to concrete structures. Availability of cheap wood, flexibility, and aesthetics were the major factors that induced people towards wooden structures.But the case is different for cyclone-prone coastal areas. Although the vulnerability of a structure to a cyclone is circumscribed by its siting, the possibility that a cyclone will occur, and the extent to which its edifices can be damaged by it, concrete structures are always preferred than wooden ones. Concrete buildings, although ordinarily more expensive than wood frame structures, are totally worth it in the long term.
Over the past few months, a slew of fire accidents has occurred In India damaging human lives, properties and goods. In a tragic incident, 20 students died after a fire broke out in a private coaching center in Surat, Gujarat last month. Eyewitness recall that in a bid to escape the blaze, students were seen jumping and falling from the third and fourth floors of the building. This accident is just one of the countless fire tragedies in the country.
We have been talking about the pros and cons of steel and concrete as a construction material. Let’s get a better understanding on why they work better together. Anyone reading about construction materials would have come across the saying – Concrete is good against compression, but weak in tension whereas steel bars are good in tension, but weak in compression. What a few had inferred from the statement is that, steel is naturally weak in the face of compressive forces, which is not the case. Steel is good in both compression and tension. Steel bars or steel reinforcement bars are weak in the face of compressive force due to their dimensional property. Steel reinforcement bars have an insignificant cross sectional area when compared to the length of the steel bars, and thus the ability to withstand compressive forces are naturally less.
The construction of a commercial or residential building cannot be imagined without the use of concrete and steel. These two components are the most essential composite in the construction field. The reasons why they are preferred is their advantages in terms of strength and withstanding the loads. However, what if a comparison was made between concrete and steel. To see which one tops the other in terms of certain parameters.
So, which material surpasses the other in the field of construction – concrete or steel?. We know that both are important for constructing a structure but let us find out what these two materials are capable of.
From the previous blog Part-I of this series, the concept of underwater concreting and how it became the preferred concreting method for construct structures whose foundation is laid on water. The main advantage of underwater concreting is that it prevents the issues of washout by the addition of addictive components.
With the emergence of better technologies, techniques for underwater concreting has become innovative and has led to the discovery of better methods which will be explained in the following section.
We all know that concrete is the vital material needed for the construction of any man-made structures. Without concrete, literally, no construction of buildings, bridges, dams and other structures etc is possible. Concrete is known for its incredible compressive strength.
Normally concrete is used in constructing buildings whose foundations are built on the land but during the construction of structures like bridges, dams etc, the foundation part of the structure lies underwater, therefore in these cases, underwater construction is the only possible method.
When it comes to bridges or any other man-made structures like buildings, they all have an estimated lifetime after which they start to show signs of wear and tear. However, the signs can be delayed for much longer if the structure is given proper periodic maintenance and the construction of the structure using quality materials.
With the emergence of innovative ways and materials in the construction field, it is currently possible to build structures that are more strong and durable than the ones constructed long before. But even the newly constructed structures are collapsing after or during the construction phase but some of the old ones still stand intact, therefore, this raises a question about the integrity of the structure.
Steel is an indispensable part of construction. The possibilities presented by steel in the field of construction is not just limited to steel sections, but also as steel bars as reinforcement to cement concrete in construction of structures. The story of steel as a reinforcement presents a picture of innovation in the field of construction. Starting as iron as reinforcement to structures, to highly ductile mild steel to deformed bars (High yield strength deformed bars) and finally to thermo mechanically treated (TMT) steel bars, showcase an evolution of steel reinforcements to keep up with the needs presented by humans in the field of construction.