From Bridges and Ferry Terminals, to Waste Water Treatment Plants and Transfer Stations, Metro's crew is well versed in the variety of complications associated with working around the public, dealing with various scheduling issues – and in confined, sometimes hazardous spaces.
We pride ourselves in our ability to come up with solutions that work well for our clients and our crew that meet or exceed expectations.
WASTE WATER TREATMENT PLANT
The sewage treatment plant of a major metropolitan city required us to go into each of thirteen pre-aeration holding tanks. The covers installed over these tanks trap H2S gas between the effluent water and the covers. The H2S gas reacts with the exposed concrete, creating sulphuric acid which degrades the cement paste.
The repair work was conducted in a confined space and within a biohazardous work environment. We implemented a detailed confined space entry work program with full-time air monitoring and active ventilation to ensure the safety of our crew.
We found that hydro demolition with a 20,000 psi hydro unit was the most effective method of exposing a sound substrate. Once all the deteriorated concrete has been removed, a 50 mm x 1200 mm shotcrete repair is applied to the prepped surface.
The value was between 2.5 and 3 million dollars.
We have been involved in a variety of water reservoir projects required to decrease the amount of water leaking and being wasted. One reservoir required work due to deteriorated joints and concrete edges caused by extended time of fresh water leaching of the cement particles from the concrete surface. Another reservoir had poor initial workmanship from leaving shotcrete rebound around the bottom edges, creating easy passage for water to leak out.
Our team has been able to assess the problem, assemble the required procedures needed to fix the problem, and subsequently carry out the work required to greatly decrease the amount of water leaking from these reservoirs.
BRIDGES IN NEW WESTMINSTER
There were two bridges in New Westminster that linked a residential area to the rest of the city that needed joints to be repaired, as well as a retaining wall along a well-used road.
The challenge we faced in this job related to scheduling for the different aspects that needed to be accomplished without drastically impacting those who use these key roads.
FERRY TERMINAL - RE & RE OF TOPPING ON TRANSFER DECK
Metro preformed work on the transfer decks of a well-used ferry terminal that had multiple cracks and spalls. The deck is subject to a large amount of stress caused by the weight it holds on an everyday basis. Metro removed and replaced the topping for the berth 3/4 transfer deck and scissor ramps. Jeene® joints were also installed at key slab joint locations to facilitate expansion/contraction movement to increase the lifetime of the structure.
FERRY TERMINAL - REPAIR TO PASSENGER LOADING CONCRETE DECK
A passenger loading area of a metropolitan ferry terminal was in need of repair. Metro was able to supply the labour and materials needed to prepare the surface for a membrane application, and seal existing cracks using epoxy injection expertise. All this while keeping the public out of the work area, and not interfering with the scheduled ferry traffic.