Bumper growth is unquestionably underway in Africa’s cement and concrete and construction industries.
In 2014, Africa construction sector attained a growth of 46.2%, with a total of 322 different collected projects in all sectors of construction, representing a total value of US$ 222,677 million. Knowing more about concrete in Africa can go along way to helping the construction industry grow more.
ARE YOU LOOKING FOR WATERTIGHTNESS?
Consider waterproof concrete!
Does your project require you to undertake major construction works, such as underground basements, parking lots, or shopping centers? Are you concerned with the impermeability of your structure? In other words, do you need concrete water tightness?
Despite the apparent density of concrete, it can be described as a porous material that allows the passage of water through a structure of capillary pores.
These capillaries are the voids created by the water in the concrete that is necessary to start the chemical reaction for hardening known as hydration.
To cope with such a challenge, it is highly recommended to implement a technology that reduces the water cement ratio (capillarity) whilst producing a highly workable concrete to aid placing and compaction. Indeed, concrete the lowering of the water cement ratio reduces the volume, size and continuity of the capillary structure.
The water impermeability of a construction is determined by fulfillment of the decisive requirements regarding limitation of water permeability through the concrete: Water penetration depth, Water conductivity, Water absorption, Self-healing properties of a concrete.
Careful selection of key technologies and products is vital to meet the demands expected of a watertight structure. The provision of the most advanced technologies from a comprehensive range of products involved in the composition of the concrete structure will ensure that all system components are compatible.
ARE YOU BUILDING HIGH-PERFORMANCE STRUCTURES?
Choose high strength concrete!
Does your project require you to undertake audacious, high-performance civil engineering works, such as bridges, roads?
Are you concerned with the high performance and durability of your structure? In other words, do you need high strength concrete?
High-strength and ultra high performance concretes are not just cutting-edge technologies for scientific research, but also continue to find new applications in practice. Whether in dealing with the slenderness of building components (e.g. design) or dimensional instability under extreme conditions (e.g. earthquake stresses), high and highest material properties (compressive and flexural strength, elasticity and ductility) are finding entry in concrete technology. Durability and high strength of concrete are thereby interdependent.
The durability of the concrete in Africa is a particularly important topic when designing a concrete structure.
Such high durability concrete is typically used for the following types of applications and structures:
• Dams and watertight structures
• Sewage treatment plants and chemical plants
• Concrete structures in extreme (low or high) temperature conditions
• Bridges, galleries and tunnels, etc.
• Hydraulic structures and industrial flooring to withstand abrasion or heavy traffic
Improved durability will result in:
• Prolonged service life of concrete structures and elements
• Lower costs for maintenance and refurbishment works
• Less repair work, minimizing traffic disturbances
• Improved appearance of the concrete surfaces
• More satisfied customers
DO YOU NEED FAST-BUILT AND AESTHETIC STRUCTURES?
Adopt precast concrete!
Does your project require you to build precast structures (beams, poles) or aesthetic building fronts? Are you concerned with the fast-building or the esthetics of your structure? In other words, do you need concrete precast concrete?
Precast concrete is used to build structures that are delivered after hardening. Concrete used for the production of precast structures requires an industrialized production process, and a good concrete mix design in order to best serve its specific requirements, such as fast placing and compaction, fast turnaround of moulds and fine surface finishes. The use of precast concrete technologies will help reduce your cost and improve your production process.
One common example of typical use of precast concrete is tunnel segment production, Modern tunneling methods in weak rock conditions demand concrete segments which are immediately load bearing as linings to the fully excavated tunnel section.
Precast concrete units called tunnel segments perform this function. It combines the challenge of realization of a specified high early strength and fulfillment of highest requirements regarding durability. Strength development is usually secured by utilization of heat or steam curing which can be contradictory to durability if the concrete core temperature is too high.
CHOOSE GREATER QUALITY FOR YOUR CONCRETE, FOR AFRICA
Designing an entire watertight building from the basement to the roof requires the development of solutions for the widest range of applications, solutions which can be installed practically and provide permanent protection. For a complete structure this means the sealing of surfaces such as roofs, underground walls or foundation plates. It also means assuring the water tightness of construction joints and of movement joints. Furthermore, Specialty in chemicals is our business and trust is the foundation of our success.
We strive to invest locally in people and techniques, to optimize specific knowledge of local market and specific solutions to local challenges. Waterproofing solutions in visible areas must meet high aesthetical requirements.
Alongside water, building structures are exposed to abroad range of forces and strains, starting with mechanical stresses resulting from the type of construction and extending to various external attacks.
Extreme hot or cold temperature conditions, aggressive water or other chemicals, continually rolling, abrading or pulsating strains on surfaces, or in extreme cases the impact of fire, places enormous stresses on structures as a whole and on building materials.
To tackle such trials, it is highly recommended to determine the fundamental needs of your structure, among which the main ones are waterproofing and/ or high strength and/or precast production.
Author:
Jean de Martres
Area Africa Manager chez Sika
www.sika-africa.com
