Lime (Hydraulic) and Cement: Key Building Materials in Construction

What Is Lime (Hydraulic)?

It is an important binding material used in building construction. Lime has been used as the material of construction from ancient times.

When it is mixed with sand it provides lime mortar and when mixed with sand and coarse aggregate, it forms lime concrete. Lime is a good building material for construction its use in the construction of foundations, walls, plastering, white washing is known to you.

Structures like forts monuments, please, bridges constructed years back stands today in good condition of time.

The use of lime has been reduced with the introduction of cement. This is because of cement.

Takes less timer fro setting
Has More Strength
Having desired Properties
Stored for longer periods etc.

Types of Limes

Fat lime:
Hydraulic lime:
Poor lime:

What Is Cement?

Cement is a commonly used binding material in the construction. The cement is obtained by burning a mixture of calcarious (calcium) and argillaceous (clay) material at a very high temperature and then grinding the clinker so produced to a fine powder.

It was first produced by a mason Joseph Aspdin in England in 1924. He patented it as portland cement.

Different Types of Cement

Sr.No.	Type of Cement
1	Ordinary Portland Cement (OPC)
2	Portland Slag Cement
3	Portland Pozzolana Cement (PPC)
4	Coloured Cement/White Cement
5	Sulphate Resisting Cement
6	Low Heat Portland Cement
7	Rapid Hardening Cement
8	Hydrophobic Portland Cement
9	Extra Rapid Hardening Cement
10	Quick Setting Cement
11	Super Sulphated Cement
12	Portland Pozzolana Cement (Fly ash based)
13	Portland Pozzolana Cement (Calcined based)
14	Air Entraining Cement
15	Masonry Cement
16	Expansive Cement
17	Oil Well Cement
18	Rediset Cement
19	Concrete Sleeper Grade Cement
20	High Alumina Cement
21	Very High Strength Cement

Difference Between Lime and Cement

Sr.No.	Detail	Lime (Hydraulic)	Cement
1	Slaking	Hydraulic lime is available in quick from. Slaking of hydraulic lime is necessary before its use. Process of slaking takes considerable time construction work is delayed.	For cement slaking is not necessary it can be used directly as and when required. No delay in construction.
2	Setting	Hydraulic lime contains silicates and aluminates of calcium and oxides of iron. There compounds are hydrated during setting and from the intricate crystalline structure. This action is similar to cement. Due to this phenomenon, hydraulic lime sets under water. Calcium oxide of hydraulic lime is converted to calcium carbonate which is a hard substance and which acts as a binder. It sets slowly hence delays the construction process.	Four important compounds C3SC2SC3A and C4AF take part in setting C3A (Tricalcium Aluminate) as soon as the water is added hydrolysis starts. To allow for a time of mixing. for transportation and proper placing 2 to 3 % gypsum is added to the cement. C3A causes an early setting of cement with a generation of a lot of heat, which is not desirable. Its action gets complete in 28 hours.(Remember setting is not hardening to setting means changing from plastic stage to solid stage) C3S (Tri calcium Silicate) is next to set and harden. It gives early strength. C2S (Dicalcium Silicate) Its reaction is slow. Hardening starts after 7 days and continues up to one year. C4AF (Tetra Calcium Alumina Fluorite) This is in active and does not play any role in setting. It takes less time for setting hence progress of construction is not delayed.
3	Binding	Hydraulic lime posses binding property and eminently hydraulic lime can be used as cement. However, its binding strength is much less than cement. As per the classification of National building code lime mortar having, 1(Eminently hydraulic lime) :2 or 3(sand) proportion possesses compressive strength of 2 N/mm² Hydraulic lime can not be used for binding reinforcement in cement.	Cement prosses strong binding properties compared to lime. As per the classification of national building code cement mortar having 1:6 (Cement)(sand)proportion possesses compressive strength of 3 N/mm² Cement can be used for binding reinforcement in concrete.

FAQ: Lime (Hydraulic) and Cement in Construction

What is hydraulic lime and how is it used in construction?

Hydraulic lime is a type of lime that sets through hydration reactions with water and can even set underwater. It is used in construction for making lime mortar and lime concrete.

What are the main differences between lime (hydraulic) and cement?

Lime (hydraulic) requires slaking before use and sets slowly, while cement can be used directly and sets quickly due to chemical reactions involving compounds like C3S and C2S.

Why has the use of lime decreased with the introduction of cement?

Cement offers advantages such as quicker setting times, higher strength, and the ability to bind reinforcement in concrete, which lime does not provide to the same extent.

What are some types of cement commonly used in construction?

Types of cement include Ordinary Portland Cement (OPC), Portland Slag Cement, Portland Pozzolana Cement (PPC), and various specialized types like Sulphate Resisting Cement and Rapid Hardening Cement.

Can hydraulic lime be used interchangeably with cement in all construction applications?

No, hydraulic lime has lower binding strength compared to cement and cannot be used for binding reinforcement in concrete as effectively as cement.

How does the setting process of hydraulic lime compare to cement?

Hydraulic lime sets through hydration of silicates and aluminates, similar to cement, but at a slower pace, which can delay construction compared to the rapid setting of cement.

What historical structures were built using lime that still stand today?

Many historical forts, monuments, and bridges were constructed using lime-based materials, showcasing their durability over time.

Are there specific applications where lime (hydraulic) is preferred over cement?

Lime (hydraulic) is preferred in applications where slower setting and historical restoration are priorities, due to its compatibility with older building materials and techniques.

How does lime mortar compare to cement mortar in terms of compressive strength?

Lime mortar typically has lower compressive strength (around 2 N/mm²) compared to cement mortar (around 3 N/mm²), as per the classification of the National Building Code.

What are some environmental considerations when choosing between lime and cement in construction?

Lime production generally has a lower carbon footprint compared to cement production, making it a more environmentally friendly choice in some contexts.