An anchor portal or H-frame tower is a

gantry A gantry is an overhead bridge-like structure supporting equipment such as a crane, signals, or cameras. Devices and structures *Gantry (medical), cylindrical scanner assembly used for medical 3D-imaging or treatment *Gantry (transport), an over ...

structure supporting

overhead power line An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. It consists of one or more conductors (commonly multiples of three) suspended by towers or poles. ...

s in a switchyard. Their static function is similar to a

dead-end tower A dead-end tower (also anchor tower, anchor pylon) is a fully self-supporting structure used in construction of overhead power lines. A dead-end transmission tower uses horizontal strain insulators at the end of conductors. Dead-end towers may b ...

. Anchor portals are almost always

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

-tube or steel-framework constructions.

Gallery

Power line Morales1.jpg, A simple H-frame anchor tower consisting of two poles and one horizontal crossarm, bearing similarity to the letter H Abspannmast_Abspannportal.jpg, anchor pylon and anchor portal, 380kV UW-Birkenfeld_Abspannportal.jpg, anchor gantry, 110kV UW_Seewiesen_Zuleitung.jpg, diagonal frame Huge gantry tower in Golczewo.jpg, Multi-level gantry tower Mastportal Pszenno.png, Gantry tower with road underneath

References

Pylons Electric power infrastructure {{Engineering-stub