Although water helps make concrete mixture workable, the strength of concrete is inversely proportional to the amount of water added or water - cement (w/c) ratio. Hence, to get stronger concrete, water dosage should be controlled. Other disadvantages of using too much water are loss of cohesion, bleeding, segregation and possibility of shrinkage cracks.
Superplasticizers, also known as high range water reducers, are chemical admixtures used where well - dispersed particle suspension is required. These polymers are used to improve the flow characteristics of suspensions such as in concrete applications. Their addition to concrete or mortar allows the reduction of the water to cement ratio, not affecting the workability of the mixture, and enables the production of self-‐consolidating concrete and high performance concrete.
SuperPlast series of superplasticizers have a retarding effect on the concrete mixture. That means the setting time is extended to ensure the cement does not start hardening immediately.
The prescribed dosage of various SuperPlasts is as shown in the adjacent table. However it is necessary to carry out site trials in order to determine the exact ratio before implementation.
The purpose of air entrainment is to increase the durability of hardened concrete and also to increase workability of concrete while in plastic state. During monsoons, the water occupying the pores in concrete expands and creates stresses, which lead to tiny cracks. This allows more water to enter and adds to the stress on the concrete, which eventually leads to its failure.
The air bubbles in AEROPLAST are typically 10 to 500 μm in diameter (0.0004 to 0.02 in) and are closely spaced. The air bubble can be compressed a little, and so the bubbles act to reduce or absorb stresses.
AER MS Silica fume is added to cement to improve its properties, in particular its compressive strength, bond strength, and abrasion resistance. These improvements stem from both the mechanical improvements resulting from addition of a very fine powder to the cement paste mix as well as from the pozzolanic reactions between the silica fume and free calcium hydroxide in the paste.
Addition of AER MS Silica fume also reduces the permeability of concrete to chloride ions, which protects the reinforcing steel of concrete from corrosion, especially in coastal areas, which are chlorine - rich, humid areas.
Cement requires a moist, controlled environment to gain strength and harden fully. Hydration and hardening of concrete during the first three days is critical. Abnormally fast drying and shrinkage due to factors such as evaporation from wind during placement may lead to increased tensile stresses at a time when it has not yet gained sufficient strength, resulting in greater shrinkage cracking. The process through which the early strength of the concrete can be increased through hydration is called 'Curing'.
Apart from preventing seepage and damage, other benefits of water - proofing are
Reflective roofs lead to saving of power and hence cost by reducing the amount of cooling required during summers. Most common applications of reflective roofs are at
Reflecto not only provides reflective surfaces but also water and crack resistance
Yes! In fact, to use EZ - PATCH is as easy as these three steps: