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Concrete Restoration & Concrete Renovation
What is Shotcrete Or Gunite?
Shotcrete is a process in which compressed air forces mortar or concrete (wet or dry) through a hose and nozzle onto a surface at a high velocity.
In the Construction Industry
• Shotcrete - Is typically defined as the “Wet Process”
• Gunite - Is typically defined as the “Dry Process”
Shotcrete or “Wet Process”
• Receives wet product from local ready mix supplier
• Material is fed into the pump via shoot• Shotcrete product is pumped through hose
in the wet state• Air is added at the nozzle
Shotcrete (Wet Mix) Equipment
Wet mix is Shotcrete in which all of the ingredients are mixed before introduction into the pump and delivery hose.
Gunite or “Dry Process”
• Materials on site in dry state/premix• Materials fed from mixer-hopper-
pressurized hopper• Gunite (dry material) is pumped
through hose• Water is added at the nozzle
Gunite (Dry Mix) Equipment
Gunite (Dry Mix)
• Dry Mix is a blend of raw materials (cement and aggregates) or premix
• Water is added to the mixture at the nozzle and the mixed ingredients are projected onto the application surface
• Fibers (Steel or Poly) can also be used
Gunite Materials
• Portland Cement• Sand/Agg.• Fibers• Water• Admixtures
Shotcrete/Gunite-Advantages
• High production• Little area needed for staging• Total control of product• Access to work areas from long distance• No forms required• Confined space applications• Easy to finish
Like Concrete – Shotcrete must also adhere to:
• ACI Standards
• ASTM Standards
• Certified Applicators/Nozzle men
All these are specified as job requirements.
All of our crews have at least one Nozzle man per crew.
Damaged Culverts• A major to concern to a growing number of cities
and DOT officials is the effect of erosion and rust to previously installed Corrugated Metal Pipes
• Unfortunately out-of-site/out-of-mind
Damaged Culverts
Culvert damage that goes unattended can cause major roaddamage, safety concerns, and additional costly repairs
Damaged Culverts
Culvert washouts are a major concern on highways and roadways
Culvert Damage
Deteriorated sewers that are in eminent danger of collapse can be restored permanently with SHOTCRETE at a fraction of the cost of replacement.
Culvert RestorationYears of water, sand, gravel, and other debris take its toll on the bottom of Corrugated Metal Pipe.
This causes the water to run underneath the pipe washing away any support, causing this risk of the pipe to collapse on itself.
Invert Repairs
Full Perimeter Repairs
Pipe Identified as needing repair Wire mesh installed around pipe
Shotcrete is applied by Nozzle man Repaired pipe is complete
Sewer Rehabilitation
Repair
Repairing a damage CMP causes no damage to roadways, minimum disruption of traffic, and is very cost effective.
Repair vs. Replace
Replacement options often include extensive digging, disruption of traffic, and other daily routines, and long periods of repair.Other liners are extremely expensive and cured-in-place liners, or slip lining, can lead to reduced flow capacity.
Replacement
Picture Courtesy of Auburn Township-Geauga County, Ohio
Here we see what is involved in replacement of a CMP. Closure of roadways, disruption of traffic, and repair to roadway are just a few issues that come with the job.
Replacement
Traffic disruption associated with culvert replacement can cause lane closures, traffic back-ups, and slowed commute time.
Culvert Restoration using Shotcrete
• Cost Effective vs. Replacement• Provides structural integrity• Improves flow by reducing the roughness
coefficient• Repair without interference with existing
utilities• Maintains flow in line while rehabilitation is
accomplished• Minimum disruption of traffic• Environmentally Friendly
Culvert Repair
The environmental benefits of using trenchless technology must not be overlooked when working near rivers, streams and environmentally sensitive areas such as wetlands.
Bridge Rehabilitation
BEFORE
AFTER
Retaining Walls
Ditch Lining
Seismic Retrofit
Recently reinforced walls at Memphis' historic Downtown Customs House and Post Office.
Seawalls and Piers
• Shotcrete is not a new process and it continues to be a primary solution for Engineers, DOT, and Municipalities.
• Shotcrete applications continue to progress and expand every day.
• The applications of Shotcrete may not be known by everyone, but are seen by millions every day.