ANSWER
Advantages of flexible joints over rigid joints include:
(i) Flexible joints produce the economy of expansion but rigid joints are prone to damage under bad ground conditions.
(ii) Rigid joints are usually applied to pipes of smaller bores made mainly of clay or concrete materials while flexible joints could be applied to both small and bigger sizes of pipes providing additional protection to the joints.
(iii) Flexible joints when jointly used with the pipes have ability to absorb movement and distribute the pressure uniformly over the surface area of its coverage.
(iv) Flexible joints are made of more durable materials and can withstand both thermal and other forces exerted on them.
