The ASA Contractor Qualification Program (CQP) is a straight-forward program that helps to establish a shotcrete contractor’s qualifications through review of the contractor’s work, by the ASA Contractor’s Qualification Review committee, whose members have extensive experience in successful shotcrete work. This qualification program provides a distinct service to the industry by assuring specifiers that shotcrete contractors reviewed here have a proven record for completion of successful projects of similar work and scope.
Specifiers are encouraged to require the ASA Qualified Shotcrete Contractor (QSC) for their specific projects, selecting the appropriate level of qualification (Structural Level I or II, or Pool) based on the difficulty of application, in the process (Wet-Mix or Dry-Mix) specified. Qualified Contractors will be posted on the ASA website and promoted in Shotcrete magazine and at the various venues where ASA is represented.
ASA Qualified Shotcrete Contractor Level I or II (QSC – SI or SII)
The majority of self-performing shotcrete contractors would seek this qualification. There are two levels of qualification, Level I Level II (SI or SII) in the process(es), i.e. wet-mix or dry-mix, to the work performed by applicant.
Qualified Shotcrete Contractor – Structural Level I (QSC – SI) – which have thin, lightly-reinforced shotcrete sections that can be easily accessed and placed would be considered “Level I”.
Qualified Shotcrete Contractor – Structural Level II (QSC – SII) – Projects which have thick, heavily-reinforced sections or sections with difficult access would be considered “Level II”.
ASA Shotcrete Contractor Education (aka CQ Seminar) – this seminar represents best practices for the self-performing shotcrete contractor and provides guidance to complete your CQ application.
ASA Qualified Shotcrete Contractor – Pool (for self-performing)
This qualification program is tailored to the specific needs and unique practices of the pool industry. This qualification is available in the process(es), i.e. wet-mix or dry-mix, in which the applicant self-performs.
ASA Shotcrete Contractor Education (aka CQ Seminar) – this seminar represents best practices for the self-performing shotcrete contractor and provides guidance to complete your CQ application.
The American Concrete Institute (ACI) established the Shotcreter certification program to establish a basic skill level for shotcrete placement. A design engineer or specifier should always require an experienced and qualified contractor for support, which includes experienced crew members and the proper equipment including material selection for the specific project. This gives the specifier assurance that the entire shotcrete team (qualified contractor, ACI certified shotcreter, and experienced crew) have proven their knowledge and ability to consistently place quality shotcrete.
Certification credentials are issued by ACI in either process (wet-mix or dry-mix) in the vertical orientation, with overhead available as an additional credential. The education and testing are provided by Sponsoring Groups authorized by ACI. The American Shotcrete Association (ASA) is the primary sponsoring group consisting of ACI Approved Examiners for the Shotcreter certification program.
Listed below are informational items designed to explain the certification process, costs, required forms, and proper use of certification by owners and specifiers.
Call ASA at 248.983.1702 for questions regarding the program or setting up a session.
Hiring a shotcrete contractor solely because he employs a certified shotcreter is short-sighted and irresponsible. Make sure the contractor and his team is well qualified and experienced with your type of project. Due diligence and proper use of shotcreter certification, as outlined below in the “Certification User’s Manual,” could be the difference between the failure and success of a project. The extra work upfront will pay off exponentially as the speed, quality, versatility, and economic advantages of shotcrete are fully realized.
Earth and rock excavations are effectively stabilized with shotcrete and a variety of reinforcement and anchoring systems. Using shotcrete to stabilize soil for excavation has advantages over traditional timber and steel shoring techniques. Shotcrete is also ideal for ground support in tunneling and mining. It provides early ground support after blasting or excavating; early strength development, which provides flexibility to allow for ground stabilization and stress relief; and offers the ability to conform to the natural irregular profile of the ground without formwork, which makes it ideal for any tunnel. It is also the preferred material/process for underground stations, side drifts, shops, and provides long-term stability. It can be used as a final or permanent lining for underground structures.
Shotcrete is often the best alternative when repair and restoration are being contemplated and can be the ideal application method for both reinforced and nonreinforced construction. From tanks and pools to chemical and automotive to retaining walls and highway structures, the opportunities are endless.
The shotcrete professional must be able to integrate new materials with in-place construction to form a composite that will stand up to exposure and use. As important as the materials is the coordination of effort from a properly qualified contractor, materials supplier, engineer, and architect. When all of these pieces are in place, the exceptional benefits of the shotcrete process are realized.
Stay Current on the latest shotcrete industry trends, strategies, challenges, and opportunities
Receive Project Leads through project bid alerts and project listings
Gain Exposure through a variety of tools available to members, such as the ASA Buyers Guide
Influence ASA’s direction in serving members and growing the industry
Save significantly on ASA products and services
Grow Your Industry
Educate the construction world on the advantages of the shotcrete process through in-house presentations to engineers and specifiers
Promote the benefits of shotcrete at national trade shows
Coordinate proper specification of shotcrete in private and public specifications and national codes and standards
Engage DOT and other Public Authority officials with a variety of ASA resources and outreach efforts
Take advantage of Targeted Marketing in national and regional organizations and publications
Enable owners and specifiers to embrace shotcrete with a portfolio of tools designed to give them an understanding of and confidence in the shotcrete process
At a time when more and more companies are demanding effective use of their dollars, more companies in the shotcrete industry are realizing the benefits of becoming an ASA Sustaining or Corporate Member.
An ASA Qualified Shotcrete Contractor shall adhere to the following QSC Code of Conduct: “As an ASA Qualified Shotcrete Contractor, we agree to ongoing compliance with the requirements and standards set forth in the ASA Shotcrete Contractor Qualification Program description. We will not knowingly or purposefully violate any project specifications or requirements. We agree to maintain required insurance coverage, staff our projects with trained and certified personnel, and strive to produce a high-quality product in a safe and professional manner.”
Shotcrete has often been described not as a material but as a process. Both wet and dry processes produce a material that exhibits superior hardened properties to high quality conventional concrete, such as high strength, low permeability, and high durability.
Although the hardened properties of shotcrete are similar to conventional cast-in-place concrete, the nature of the shotcrete placement process provides additional benefits, such as excellent bond with most substrates and instant or rapid capabilities, particularly on complex forms or shapes.
The properties of both wet- and dry-process shotcrete can be further enhanced through the addition of many different additives or admixtures such as:
Silica Fume — Provides reduced permeability, increased compressive and flexural strength, increased resistance to alkali and chemical attack, improved resistance to water washout, reduced rebound levels, and allows for thicker single pass applications;
Air-Entraining Admixtures — Improve pumpability and adhesion in wet-process shotcrete and freeze-thaw durability in both wet and dry processes;
Fibers — Control cracking, increase toughness values, improve impact resistance and energy absorption; and
Accelerators — Improve placement characteristics in adverse conditions, allow for thicker single pass applications, increase production capabilities, and reduce the occurrence of fallouts on structures subjected to vibration.
The numerous advantages of the shotcrete process are especially evident when viewed from a sustainability point of view. Unlike many sustainability claims that are based on political or social ideals that are often difficult to quantify and substantiate, the sustainability advantages of the shotcrete process directly and positively impact the economic side of a project, falling in-line with traditional business decisions such as material, labor, and time savings as well as improved quality.
In addition to the following “top ten” sustainability advantages of shotcrete, ASA’s Sustainability page offers a wealth of information on the topic.
Formwork savings of 50 to 100% over conventional cast-in-place construction;
Formwork does not have to be designed for internal pressures;
Complex shapes require very little, if any, formwork;
Crane and other equipment savings or elimination;
Labor savings of at least 50% in repair applications;
New construction speed savings of 33 to 50%;
Speed of repair reduces or eliminates downtime;
Better bonding to the substrate, which enhances durability;
Adaptability to repair surfaces that are not cost-effective with other processes; and
Ability to access restricted space and difficult-to-reach areas, including overhead and underground.
Wet or Dry?
Although both wet and dry shotcrete have specific benefits, advancements in both material and equipment technology make both processes almost interchangeable. In most applications, the preferred method is determined by:
Economics;
Availability of material and equipment;
Site access; and
The expertise and preference of the contractor.
Today, rebound levels, dust levels, and properties such as bond strength, compressive strength, and durability can be similar whether the wet or dry method is used.
The shotcrete process is truly one of the most versatile processes available for the use of concrete in both new construction and repairs. Shotcrete can be used in almost any concrete project and typically results in a significant savings of time and money. The following list is a sample of the almost limitless applications for shotcrete.
Shotcrete, the quarterly publication of ASA, is the leading magazine of the shotcrete industry, and is designed to educate and promote the use of shotcrete as a method of placing concrete.
ASA produces member and nonmember editions of a monthly e-Newsletter titled, “What’s in the Mix.” These monthly e-Newsletters keep you informed of your association’s new products, services, events, and other initiatives.
