What Is Plain Cement Concrete (PCC) In Construction?
What Is Plain Cement Concrete (PCC) In Construction?
PCC or Plain Cement Concrete is a mixture of cement, fine aggregate, and coarse aggregate. It is an essential component in the construction process and is used to create a flat and even surface before beginning R.C.C (Reinforced Cement Concrete) or masonry work.
It acts as a barrier to prevent water from seeping into the soil and by extension, also prevents the soil from extracting water from the concrete’s aggregates. PCC is therefore an important part of any construction project that requires a strong foundation structure.
What Is The Thickness Of PCC?
PCC, or Plain Cement Concrete, is usually laid with a thickness of 100mm due to its ability to act as a barrier against moisture and soil, while also allowing it to hold well onto the structural grade concrete that lays atop it.
This helps ensure that the base layer can support the weight of the structure without any problems. PCC also allows for stability in regions that have expansive soils by helping counter eventual shrinkage or expansion brought about by changes in moisture content.
Thus, PCC is one of the most important elements in any construction project as it serves both functional and structural purposes.
Which Grade Of Cement Is Used For PCC?
M15 grade cement is commonly used for plain concrete works such as leveling courses, bedding for footing, beams, columns, etc. This grade has a mix ratio of 1:2:4 (1 cement, 2 sand, and 4 aggregates) which makes it ideal for use in PCC applications.
It is suitable for all types of construction works like plastering, masonry work, and reinforced concrete structures that require a compactable and durable material.
Why Is 40 Mm Aggregate Used For PCC?
40mm aggregate is commonly used in PCC (Plain Cement Concrete) due to its economy for substructures and highly crowded structures.
It is also used in PQC (Pavement Quality Concrete) with 31.5 mm and DLC (Densely Laginated Concrete) using 26.5 mm of aggregate, while 20mm is considered as NMSA( Nominal Maximum Size of Aggregate). For mass concrete dams, up to 150 mm of aggregate can be used.
Which Is Better OPC Or PCC?
OPC and PCC are both commonly used cement types, but there is a considerable difference in their manufacturing technology. OPC requires 95% of clinker for its production while PCC only requires 65%-80% of clinker.
This has an impact on their strength and durability; although PCC has comparable strength and durability to OPC, it may require more frequent replacements due to the lower clinker content.
Consequently, it can be said that while the two cements are similar in many ways, they differ when it comes to cost-effectiveness and longevity.
What Is The Curing Period Of PCC?
The curing period of Polymer-Cement Concrete (PCC) involves 5 days of wet curing and then air-dry curing until the time of testing. This is carried out to ensure effective hydration of Portland cement and proper setting of the polymer.
During wet curing, PCC must remain submerged in water to enhance hydration, followed by an air-dry curing period which hardens the concrete and provides a stronger bond between cement particles.
The length of the dry cure depends on various factors such as the ambient temperature, humidity, and type/strength of Portland cement used. A longer dry cure period is beneficial for ensuring that all components are properly cured before any performance tests are conducted.
