The PARS System for innovative strengthening, repair and enhancement of masonry parapets

Bridge strengthening using the PARS system

Disruption, collateral damage and associated risks to human life can be significantly reduced from vehicles striking parapets by strengthening the parapets using our PARS system.

Our innovative PArapet Restoration and Strengthening System (PARS) both repair and enhance masonry parapets, while causing minimal inconvenience to the public or disruption to road and rail traffic.

This system is a practical option where the strengthening of masonry parapets will reduce the risk of direct of collateral accidents by vehicle strikes.

Accurate surveys and design

We produce a finite element model of the parapet and, using dynamic analysis, we estimate the effects of a vehicle striking the parapet. We then add masonry reinforcement in sufficient quantity and pattern to provide the necessary increase in vehicle and/or debris containment.

A carefully developed system that is economic and practical to fit.

Gallery of illustrations:

A scene from an an accident with a car and a damaged parapet.Parapets – a diagram of the problems afflicting parapetsA dangerous parapet in the instance of a road traffic accident

Benefits of the PARS system

  • Economical, cost effective and reliable.
  • All work is undertaken from the carriageway face of the bridge.
  • No disruption for users of the thoroughfare below the bridge span.
  • Easy and rapid installation.

  • Increased strength and impact resistance.
  • Improved structural behaviour.
  • Allows normal structural movement.
  • Rapid, concealed, sympathetic installation.
  • Allows staged, sequential, installation.

  • Minimal disturbance to bridge fabric.
  • No unsightly external plates.
  • Original characteristics retained.
  • Accurate structural computer analysis.
  • Optimised software engineering design.

PARS system diagram showing SockFix anchors, Helibars and Cemties

Helifix reinforcement system

PARS installation showing where to fix the Cemties

Cross section of reinforced parapet

PARS project example of a temporary scaffold

Schematic view of a temporary work platform

The risks associated with crashing into a parapet are:

  • Injury or death from a vehicle falling through a parapet
  • Injury or death from flying or fallen debris or collateral damage from an associated accident as a result of parapet debris on the rail lines, road, path or waterway below.
  • Damaging the structural integrity of the bridge.

Structural survey of the parapet

A full structural survey of the masonry parapet is carried out detailing the critical dimensions, type and condition of the brick or stone, type and condition of the mortar and defects.

The appropriate strengthening measures are designed to meet the requirements of the Department of Transport.

The installation will commence with the setting out of the positions of the vertical anchors, longitudinal bed joint reinforcement and the transverse ties.

The temporary works platform will be installed to protect the workforce and prevent objects and debris falling from the workface to the area beneath the bridge.


The longitudinal HeliBars provide lateral continuity and distribute the stresses induced by impact throughout the masonry, the CemTies enhance the transverse resistance by maintaining the mass of masonry thus preventing bricks/stones dislodging from the parapet.

The Helifix SockFix anchors act as vertical restraints providing stiffness and resistance to the stresses transferred by the longitudinal HeliBars.

Vertical or inclined holes are drilled through the masonry parapet in order to accommodate the Helifix SockFix anchors.

After installation of the SockFix anchors. The Sockfix anchors are used to place the parapet under construction.

HeliBars will be inserted in the rebates and encapsulated with the Marflex structural adhesive.

After drilling transverse holes across the thickness of the parapet in the masonry at the prescribed locations Helifix hooked CemTies will installed and grouted.

At the completion of the installation the surface of the masonry will be cleaned and the temporary works removed.