What type of excavation involves the use of bulkheads to support active earth pressure?

Braced cut excavation involves the use of structural supports, such as bulkheads, to resist the lateral earth pressures exerted by surrounding soil. In this method, excavations are typically deeper and require stabilization to prevent collapse due to the weight of the soil pressing against the excavation walls. The use of bracing systems, which can include horizontal braces or struts, allows for a safer work environment and permits excavation in urban settings or areas with restricted space.

Open cut excavation refers to a method where soil is excavated, leaving the sides unsupported, which is suitable only for shallower depths or stable soils. Sheet pile excavation involves the installation of sheet piles to create a barrier against the soil and water, but it does not specifically utilize bracing systems like those found in braced cut excavations. Deep excavation generally describes any excavation beyond a certain depth but does not inherently describe the method used to support the sides of the excavation.

Therefore, braced cut excavation is the most appropriate answer as it directly addresses the use of bulkheads to manage active earth pressure during the excavation process.