Conveyed through a hose and pneumatically projected at a adjustable velocity onto a surface, as a construction technique to install concrete.
(Dry Mix-Process) the material may come in a bag form or bulk, the material is conveyed with pneumatics with the water added at the nozzle .In the (dry process) the Nozzleman plays a most important role with the material being placed, the mix is propelled by air velocity
which creates turbulence creating fluxions at the nozzle, the Nozzleman will use a (circular motion -etc.) to compete the hydration at point of discharge.(Recommend adding 3%-4% moisture for all Dry bag material) this will minimize dust and help final hydration of the placed mix .
(Wet Mix-process) the material is generally delivered with
ready-mix trucks per ACI 318-ASTM C94 standard specification for ready mix concrete. The aggregates are a combination of coarse and fine aggregates per ASTM 33 . The material is pumped with high pressure hydraulic concrete pumps thru a system which air is injected at the nozzle to increase the velocity
The concrete being placed may be vibrated and placed with or without the nozzle.
The Shotcrete Contractors Association works with
ACI chapters thru-out US and Canada administering the ACI Shotcrete Nozzleman Certification program which includes both classroom education and practical field education including a Concrete specific Safety class. Contact Shotcrete Concrete Contractors for session dates.
Which may include project specific mock-up's - These Pre- Construction test panels demonstrate quality control and verify the Nozzleman has the capability with the support crew including the intended mix to qualify the team to install the concrete for the project.
Including qualifying the Support required by the Shotcrete / Concrete Contractor.
Starting in the mid 1950’s wet mix Shotcrete was introduced to the construction industry – these primitive attempts proved to be very beneficial to the industry, thru the 1970’s numerous structures have been constructed with Wet Mix Concrete using the Shotcrete process as means and method to place the concrete.
In the early 1980’s the Concrete Industry takes a big step in the quality for mixing and batching ready mixed concrete, computer controlled ready mix plants are installed. Admixtures have become common and proven to increase the placement and durability of the concrete. The equipment used in the Shotcrete (wet mix concrete process) has changed full circle from the start in the mid 50’s.
Today's state of the art equipment is capable of pumping any slump and used in long distance tunnel projects as well as high rise concrete construction.
Material is generally delivered with Ready- mix trucks per ACI 318 - ASTM C94 Standard specification for ready mixed concrete. The Aggregates are a combination of coarse and fine aggregates per ASTM C-33. Concrete is pumped thru a system with air-injected at the nozzle to increase velocity and improve the placement of the concrete. The concrete being placed may be vibrated and placed with or without the nozzle in congested and horizontal applications.
The Shotcrete Contractors Association - Non-profit origination of Contractors - Engineers and others with an interest in Shotcrete .
The Shotcrete Contractors Association offer's - Education / Training / Safety Program which includes - ACI Nozzleman Certification thru ACI Chapters - US & Canada -
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