Q. Complete embedment of pipelines into thrust blocks

For unreinforced concrete thrust blocks in bends and tees for pressurized pipelines, it's recommended that contact surface between pipelines and concrete thrust blocks must not exceed 45^o from either side of pipe in the direction of thrust force through the centre of pipelines. The reason is to prevent occurrence of potential cracking arising from deformation of pipelines under loading condition. If it is essential to embed the whole section of pipelines into concrete, it's suggested to coat the pipe with a flexible material.