Types of Rubble masonry

                                          
                                                  Types of Rubble masonry

Stone masonry is divided in in two :-
(a). Rubble masonry
(b). Ashlar masonry

Rubble masonry :- In this category the stone used have either undressed or roughly dressed have wider joints, they are again subdivided as:-

(1). Uncoursed rubble masonry:- this is the cheapest, roughest and poorest form of stone masonry. Stones used in this masonry h
ave uneven shape and size and thickness of joints kept not more then 13mm.

(2). Uncoursed random Rubble :- The week corners and edges are removed with hammer, The vertical joints are not constructed in plumb. Generally bigger stones are employed as Quoins and Jambs to increase strength of masonry.

(3). Uncoursed Squared Rubble :- In this stones are make roughly squared. they can be of varrying size and are placed in irregular pattern. joints are made uniforms.

(4). Coursed Random Rubble :- these masonry are used in low hight walls or public buildings. The stones employed are 50mm to 200mm size.The joints are abbout 15mm thick. hight of each course in same.

(5). Coursed Square Rubble :- This type of masonry is made up of hammer squared stone facing with bonded backing of uncoursed random rubble masonry.These stones employed in each course are of equal hight. The hight of courses may be reduced in upper portion of wall.

(6). Built to regular Courses :- In this masonry uniform hight of stones are used in horizontal layers not less then 150mm in hight. The stones are arranged in suh a manner so that vertical joint not conside with continues courses.

(7). Polygonal Rubble masonry :- In this stones are roughly dressed to irregular polygonal shape. chips should not be used to support stones on facing.

(8). Flint Rubble masonry :- This type of masonry is used in the areas where flint is available in plentry. their thickness varies from 80mm to 150mm and in length from 150mm to 300mm.

(9). Dry rubble masonry :- This type of masonry is used in the constructiopn of retaining walls, pitching earthen dams and canal slops in the form of random rubble masonry without any mortar.