Thermal Expansion

Thermal Expansion and Contraction -Why It's Important

All modular trench drain systems on the market require a concrete encasement, therefore selecting a trench drain that will meet the wide assortments of conditions is critical to the performance and life span of a properly performing system.  Unlike typical drainage pipe, which is buried; and at a relatively stable temperature, trench drain systems are at the surface and subject on a daily basis to wide temperature fluctuations. 

ABT Inc's polymer concrete blend is specially formulated to handle the wide temperature fluctuations that are often associated with surface conditions during a daily and seasonal cycle.

HDPE has a lower modulus of elasticity and higher coefficient of thermal expansion than other trench drain materials. These properties cause HDPE trench drains to expand and contract much more from changes in temperature than other trench drain materials.  Because of HDPE thermoplastic polymeric nature ,its performance is significantly related to its operating temperature.

Because the thermal expansion coefficient of HDPE is approximately 10-15 times that of the steel and concrete it is surrounded by, when exposed to extreme temperature changes, HDPE will experience undesirable structural movements.

Example:

Thermal Load in a typical Civil Environment

Daily Temperature Variance in a 24 hr period

50°F  to  90°F  = 40°F Change

Seasonal Temperature variance in a 12 month period

20°F  to 110°F  = 90°F Change