SERVIDEK® / SERVIPAK®

Applications

Servidek/Servipak is a composite, cold-applied bridge deck waterproofing membrane and combined protection board system approved by the British Department of Transport, Specification for Highway Works, Series 2000, Clause 2003.3 for bridge decks and elevated roadways. The system will accept red tinted sand asphalt protection and hot rolled asphalt.

The two component Servidek compound is simply mixed on site to produce a viscous rubber/bitumen liquid which chemically cures to an elastomeric waterproof membrane. Servidek also acts as a strong adhesive for the preformed Servidek boards which can be trafficked after 4 hours with road laying machinery. The combined system can be laid on to unprimed, clean, dry or damp-to-touch concrete and can also act as a curing layer when applied to “green” concrete.

Servipak boards comprise selected aggregates bound with bitumen laminated between two tough asphaltic papers to form a strong protection board capable of accepting road laying equipment and hot rolled asphalt. The board allows for indentation by the base course aggregate during rolling and bonding to resist the braking forces.

Installation

Application Temperature

Servidek should be used when the ambient temperature is above 4°C or when 4°C and rising. The application should not be made if rain or frost is imminent or in conditions where it is likely to freeze before curing takes place. When the ambient temperature is below 10°C, storage at 21°C for several hours will ease mixing and application.

Surface Preparation

Concrete surfaces to be waterproofed should present a smooth surface free from sharp protrusions and hollows. Abrupt irregularities greater than 3mm should be knocked back or filled with a high strength mortar. The concrete deck should be thoroughly swept or air blown so that it is free from dust, loose stones, dirt, surface water and all other contaminants.

Mixing Servidek

DO NOT POWER MIX

Pour all of the Part B (small tub) into the Part A and stir with a timber paddle in a folding motion until a consistent colour, completely free from streaks is obtained. Ideally this should take no longer than two minutes. Mix and use one unit at a time, applying the Servidek immediately once mixed. Working life is approximately 20 minutes at 20°C.

Application of Servidek/Servipak

Pour the mixed Servidek on to the surface and spread with a Servidek Squeegee at a rate of 12.5-15 sq metres/unit depending on surface texture and temperature. Servipak protection boards should be laid while the Servidek compound is still wet and laid progressively to minimise applicator trafficking until the Servidek has cured. The boards must be close but jointed to ensure continuous protection to the Servidek, but where gaps occur these should be filled with Servidek prior to applying the Armour Tape to ensure watertightness. Where Servipak boards abut the parapet, pipe bays or abutments they should be pre-measured, and accurately cut to size by incising with a sharp Stanley knife and breaking on edge.

The joints between the Servipak boards should be primed with Primer B1, applied in 100mm wide strips with a brush or roller and allowed to dry before applying the self-adhesive Armour Tape centrally over the joint.

The Armour Tape must be firmly rolled with a Bituthene Lap Roller along its length and at junctions to ensure a watertight joint. It is advisable to seal the exposed edge of the Servipak boards at the end of each working period to prevent the ingress of moisture overnight, by tooling the Servidek compound against the exposed edge of the Servipak boards. It is good practice to ensure that the Servipak boards are bonded to the substrate by firmly rolling or light trafficking before road laying.

Base and wearing courses should be applied as soon as possible after a minimum of four hours. Bituminous material with a temperature greater than 145°C shall not be laid or deposited on bridge deck waterproofing systems, unless precautions against heat damage have been approved by the Engineer.

It is important that the waterproofing is not allowed to reach temperatures in excess of 145°C. In practice asphalt laid at higher temperatures (175 - 180°C) cools immediately to an acceptable 140°C or less interface temperature

In the event of ambient temperature exceeding 35°C, it may be necessary to lay the sand carpet by hand or to restrict machine operations to specific times of day.

On bridges which have pipe bays, abutments and curtain walls it may be necessary to waterproof with Servidek TG (trowelling grade) on vertical faces or Bituthene HD and protected with Bitushield as required. For details refer to separate data sheets. A hot climate grade of Servidek is available to suit higher ambient temperatures.