прочный

см. тж. высокопрочный

• The supporting structure must have a secure foundation.

• The concrete structure must be built on sound rock.

• A rigidly built saw-frame ...

• The housing is covered with vulcanized rubber, leather-like in appearance, but much more durable.

• High-strength steels.

• The transmitter is a robust (or rugged) unit.

• The weld must be sound and free from cracks.

• At speeds and altitudes where only the staunchest materials will serve ...

• This material is mechanically strong.

• The relays are ruggedly built.

• Such systems must be rugged enough to withstand shocks.

• Sturdy latches, substantial handles ...

• A stiff construction can be obtained by ...