Joints of Stone Masonry
The construction which is done with the help of stones and bonded together with mortar is known as Stone Masonry. Stone Masonry is widely used where the stones are available in abundance. The stone masonry is the type of masonry construction which is done with stones and cement mortar.
Stone Masonry is the art of building structures from stones. Stones are abundantly available in nature. Stones are cut and dressed into different shapes and prove to be economical material for Construction. In the stone masonry, some through stones are provided at the right angle.
General Principles Which Are Used in the Construction of Stone Masonry:
- The stones which are used in the construction of stone masonry should be hard, tough, and durable.
- The pressure which is acting on the stones should be in the vertical plane.
- The heads and the stones should not be of dumb bell shape.
- The stone should be dressed properly as per the requirements.
- A large flat stone should be used under the ends of girders and trusses two uniformly distributed loads.
- The water which is used in the construction of the stone masonry is of good quality.
- It is very necessary for to you give your stone masonry e in a proper manner for a period of 2 to 3 weeks after the construction.
- The plumb bob should be used to check the accurate verticality of the stone masonry walls.
- Stonemasonry should be design to take the compressive stresses and not tensile stresses.
Type of Joints of Stone Masonry:
There are different types of joints in the stone masonry which helps to bond with each other.
- Butt or Square Joint.
- Rebated or Lapped Joint.
- Tongued and Grooved Joint.
- Cramped Joint.
- Tabled or Bed Joint.
- Plugged Joint.
- Dowelled Joint.
- Saddle Joint.
- Slate Joint.
#1. Butt or Square Joint
The butt joint is very simple and commonly used to join in the construction of stone masonry work. In the case of butt or square joint, the dressed edge of the two adjacent stones is placed side by side. The two adjacent stones which are placed in this type of joint are abutted with each other.
#2. Rebated or Lapped Joint
The rebates are also provided to prevent the movements of the stones. The length of rebates should not be less than 70 mm. These types of joints are widely used in the construction of earthwork and coping on gables.
#3. Tongued and Grooved Joint
In this type of joint, the stone is made by providing a tongue and a corresponding groove on the adjacent stones. This type of joint is provided to prevent sliding.
#4. Cramped Joint
In the case of the cramped joint, the holes are provided on the adjacent stones. The cramps are used in this type of joint to connect the stones.
The cramped are the pieces of non-corrosive material whose ends are turned down up to a depth of 4 to 5 cm. The length of the cramp varies from 200 mm to 300 mm. The hole must be cramped with the help of cement water after placing the cramp into its proper location.
#5. Tabled or Bed Joint
Tabled joints are used where the lateral pressure is very high and it is necessary to prevent it. In this type of joint, to prevent the lateral pressure at joggle is formed on the upper surface of the bed stone.
Recess is formed on the bottom surface of the stones which laying above the bed stone. The tabled joint is widely used where the lateral pressure is to be prevented such as in the case of sea walls.
#6. Plugged Joint
The plugged joint is the same as the cramped joint. In this type of joint, the cuts are made in the sites of adjacent stones after arranging the stones in the proper position. This type of joint is widely used for coping and cornices works.
#7. Dowelled Joint
In this type of joint a hole is made into each stone and the dowels of small pieces of hard stone or brass are used to connect the stones with the help of cement mortar.
The dowelled joint is used to prevent the adjacent stones against displacement or sliding. The thickness of the dowels is used of 5 cm and 10 to 15 cm long. This types of joints prevent unwanted displacement of these stones.
#8. Saddle Joint
A saddle joint is provided to protect the joints in of the cornices. This type of joint is also known as a water joint. Saddle joints are used in the cornices and other whether surfaces to divert the water away from the joint.
#9. Slate Joint
In this type of joint grooves are made on the sides of the surface of the adjacent stones. A piece of Slate is placed between the gross of the adjacent stones.
Important Points Which Should Be Considered While Construction of the Stone Masonry:
Here are some points which should be observed in the construction of the stone masonry
- In the construction of the stone masonry, all these stones should be laid upon the natural beds.
- Stones which are used in masonry should be well seasoned hard tough and has a uniform texture.
- The stone should be free from defects like cracks and cavities.
- The vertical joints in stone masonry should be staggered.
- Proper bonding should be maintained throughout the construction of the stone masonry.
- Stones which are used for the construction of the stone masonry should be wetted before its use.
- Stone Masonry should be cured properly for at least two weeks.
- In the case of the Stratified rocks, the stone should be placed on its quarry bed surface in such a way that the line of pressure should be Normal.