Date of Award


Document Type

Master Thesis

Degree Name

Master of Engineering (Research)


Civil, Structural & Environmental Engineering

First Advisor

Brian O'Rourke


Precast prestressed hollow core floors are a widely used structural element which offers increased speed of construction, reduced self-weight and many other advantages. Due to the relatively low span-to-depth ratio and the speed of construction hollow core slabs are utilised in a large number of commercial buildings. In order to carry the services to the upper floors an opening must be made within the prestressed slab. Cutting an opening in a prestressed slab has significant effects on the structural behaviour of the slab and can considerably reduce the ultimate capacity of the slab.

This paper outlines the limited available guidance on this topic and examines the development of the prestress within the transmission length as this has a substantial impact on the effects of an opening.

A methodology for the implementation phase is outlined. The effects of an opening created by cutting prestressing strands will be modelled using the LUSAS Finite Element Analysis program and the data collected will be used to develop new and up to date guidance on this design issue.

The developed guidance will then be incorporated into a VBA Design Program which take design inputs from a user and apply them to a selected slab from an in-built database. This program will output all relevant design checks.

Access Level