Civil Engineering - Concrete Technology - Discussion

When to use low heat cement - Hydration of cement is an exothermic process that produces large quantity of heat. In mass concrete structures such as dams, retaining walls, bridge abutment, raft etc the rate of dissipation of heat of hydration from the surface is much lower than that generated.

It causes rise in temperature inside the concrete mass and may develop thermal and shrinkage cracks. Under this circumstances, the low heat cement or low heat Portland cement can be effectively used.

In low heat cement, ingredients are proportioned in such a way that C3A and C3S are formed in less amount but C2S is formed in increased amount so that C2S and C3S collectively impart the same strength as Ordinary Portland Cement (OPC).

Low-heat cement is used in dam construction for several reasons:

Reduced Thermal Cracks: Low-heat cement helps minimize the likelihood of thermal cracks in thick concrete sections, which is crucial for the structural integrity of dams.

Balancing Temperature Rise: In mass concreting projects like dam construction, where large volumes of concrete are used, low-heat cement is preferred to balance the temperature rise during the hydration process. This helps prevent excessive heat generation that could lead to thermal issues.

Improved Durability: The use of low-heat cement contributes to improved durability performance of the dam structure, ensuring its long-term stability.

Dam construction will involve mass concreting where heat of hydration is the major concern which if not monitored will cause crack in the bulk of the dam which is undesirable, hence low heat cement is preferable in this type of concreting.

The quick setting is cement generally used in under running water and for construction of massive dams, we will use generally low heat Portland cement.

For the construction of Hydraulic structures like Dams, weirs etc, Normally Pozzolana Cement is used.

Blast furnace slag used only M 20 grade.

For dam m30 grade used so used low heat cement.

Blast furnace slag cement should be used for bridge.

Low heat cement for mass constructions lika dams.

Why can't blast furnace slag cement be used?

Why partland pozzollana cement is not used?