The strength of concrete pipe joint design alone is a deciding factor for many so that they can provide a water tight connection allowing for lateral or longitudinal movement.
But to understand these pipe joint designs, we need to appreciate just how long sanitary and stormwater pipe systems have been around.
Dating back to 3200 BCE Scotland we can see remnants of early drainage systems on the Orkney Islands. And stormwater drain systems can be found in 4000 – 2500 BCE Eshnunna/Babylonia – Mesopotamian Empire (Iraq). The majority of which were constructed of sun-baked materials or cut stone.
It may not have been understood at the time, but these early adopters of drainage systems knew that you had to get these odors and wastes away from the home.
Jump ahead thousands of years and we end up at modern-day pipe joint design that is far superior to our history of when sewage was literally being dumped and drained into city streets.
Modern Pipe Joint Design
Concrete has been around for centuries and in the United States it has been used extensively in pipes for stormwater drains and sanitary systems.
Improvements in science, chemistry and technology alone have advanced the manufacturing process of concrete. This has allowed the concrete industry to create different mixing processes, better strength and even engineer different designs of pipe and pipe joints.
Engineering Pipe Joints
Pipe joints are engineered so that when a continuous line of pipe is laid, the inside of the pipe does not have irregular dips, valleys or deformities that could cause infiltration or exfiltration. The joint designs help with:
- Lateral or longitudinal movement
- Easier installation
- Strength when there is shear or vertical movement
And with all of these advantages comes a host of different types of joints. The concrete pipe industry has several joint systems to meet the performance requirements of ASTM or AASHTO standards.
- Rubber Gasket joints (our favorite)
- Preformed Flexible Joint Sealants (In accordance with ASTM C 990)
- Mortar Tongue and Groove
- External Sealing Bands
ASTM’s are consensus technical standards for a wide range of materials, products, systems and services and exist for both stormwater and sanitary sewer joints. Whereas AASHTO standards publish specifications, test protocols and guidelines which are used for storm sewers and culverts.
It’s clear that standards and practices have change over the last century and concrete pipe offers engineers plenty of options to specify depending on the application.