Today, reinforced concrete is one of the most widely used building materials in modern history. Concrete and steel complement each other. While ordinary unreinforced concrete is relatively brittle and extremely weak in stress resistance, steel or reinforced steel, on the other hand, forms a bond strength that resists tensile forces and forms a strong bond with the concrete. able to withstand applied forces and ultimately act as a singular structural element.
The advantage of concrete is that this fluid substance can be formed, molded and molded before hardening, thus giving this building material the essence of a rigid material becoming liquid in form, soft or even directly to the eye, before it even hardens to its ultimate strength. It is therefore the artistic use of this material that is brought into play here by the designer of the building.
On the other hand, reinforcing steel increases the overall strength of concrete when combined in the form of steel rods, cables, wire mesh and bars embedded in concrete before it hardens.
In the construction industry, the disadvantage of concrete compared to structural steel system is construction time, as concrete needs to be given some time to harden, while structural steel can be easily fabricated and installed immediately. Therefore, today’s new technologies and methods have improved the use of reinforced concrete to reduce the construction period.
Cast-in-place concrete or cast-in-place concrete is the most common concreting technique used on the construction site and is a preferred choice for foundations, columns, beams, slabs and walls. To shorten the hardening period or even regulate its hardening process, today’s technology is to add admixtures and retarders to the concrete mix before pouring it into the forms with the rebar in place.
Precast concrete is another form of concrete that is prepared, poured, and cured in a factory or offsite area using reusable molds or forms. Then they are delivered to site and assembled to form a complete structure. Like a Lego toy, they are connected, welded and it is economical and sometimes practical. The advantage of precast concrete is that it is fast, reduces construction time, has fewer environmental impacts such as noise pollution and dust, and ensures that the program schedule is respected.
Buildings today have a combination of cast-in-place concrete, precast concrete, and structural steelwork. The beauty of precast concrete is that steel reinforcement is already incorporated and loading stresses are also introduced into the structural member during fabrication. Much more, the performance and highlights are greatly improved.
Tilt-Up construction is another form of construction technique to shorten construction time. Here, the concrete floor base is first constructed, then the structural supports are formed and fabricated on the ground, then tilted to a vertical position. A crane is used here in particular to tilt panels or walls.
Warehouses were most notorious for using these construction methods before. Today, hotels, homes, schools, and offices now use this tilting method either as a single story or as multiple stories.
Most architects specify and use reinforced concrete, especially the most commonly used brand or brands, while most builders agree and adhere to it because reinforced concrete today is much more durable and stable, has good thermal stress, is fire resistant and requires little maintenance. The beauty of reinforced concrete today is that it will last a lifetime, perhaps even centuries from now when the architecture of the past will be much more appreciated by future generations.
Camber. Benjamin K. Panganiban, Jr., FUAP is the outgoing national president of the United Architects of the Philippines and the first national president from Mindanao.
He has been in private practice for over 34 years and is a Fellow of the PSU. He is also the first ASEAN architect and APEC architect from Davao City. He graduated with a BS Architecture from the University of Mindanao, Doctor Fellow of the Royal Institute of Architects of Singapore and a recipient of the European Business Assembly.