Portal: General

Often, various clients request our ?rm?s advice regarding the supply and application of shotcrete?be they owners, engineers, contractors, or private individuals.

Dry-mix shotcrete specimens saved from field-shot panels were tested for freeze-thaw durability

Why do we wear hard hats? Is it because the sky is falling?

Since the last update on the activities of various shotcrete organizations and committees in the Spring 2005 issue of Shotcrete, steady progress has been made with updating the documents these organizations work on

As mentioned in previous ?Sustainability? articles, one primary objective of sustainability is energy ef?ciency.

E-mails are often sent to the ASA website from engineers, contractors, builders/owners, and home owners asking for information on proper methods for curing shotcreted structures.

This article presents a procedure for up-dating your environmental knowledge and keen awareness for a deeper appreciation of our surroundings. It discusses the new regulations for implementing the procedural provisions of the National Enormental Policy Act.

It is virtually impossible to hold a discussion at a trade or technical organization meeting without the topic of sustain-ability being raised. Skeptics might describe the intense interest in this subject as one more attempt to burden society, particularly the construction industry, with little or no discernable benefit. Conversely, there are fringe groups with radical political agendas that attempt to use sustainability discussions for their own purposes. There is, however, an important central issue”the need to analyze the long-term impact of how things are designed and constructed to minimize environmental change and maximize resources as the world™s population grows. Building œgreen (constructing buildings that make efficient use of energy, water, and materials; limit impact on the outdoor environment; and provide a healthier indoor environment) is being supported by both public and private entities in recognition of the finite resources available to support a growing population and higher levels of economic activity. This is where mainstream thinking is focused and where reasonable thought resides.
To begin to understand a bit more about sustainability, it is important to answer a few basic questions.
Question: What makes concrete a œgreen building material? Answer: Concrete is a responsible choice for sustainable development. Purely as a material characteristic, durability is a significant sustainable attribute of concrete because it will not rust, rot, or burn, requiring less energy and fewer resources over time to repair or replace it. Structures built with insulated concrete have optimal energy performance. Additionally, concrete is easy to use, incurs little waste, and can be readily recycled.
Question: What is energy efficient about concrete?Answer: Concrete on its own is not a very good insulator. Recent developments in building systems, however, have combined concrete with insulation, creating highly efficient, strong, and easy-to-build assemblies. Homes and buildings constructed with insulated concrete walls use the comparative great weight of concrete to moderate daily temperature swings, as did the pueblo dwellers of centuries past. This means home or building owners can lower heating and cooling bills up to 25%. Also, heating, ventilating, and air-conditioning can be designed with smaller-capacity equipment. Along with thermal mass, high-performance insulated concrete wall systems offer high R-value and low air infiltration to provide superior thermal efficiency.
Question: How does concrete relate to recycling?
Answer: Recycling is part of concrete™s life cycle from the beginning. Several common industrial byproducts like fly ash and slag that would otherwise add to landfills are incorporated into concrete mixes. Use of these byproducts also reduces

It is inevitable that every firm will have to verify its work at some point in time. No matter how the process gets started, each contractor and supplier should be prepared to methodically respond in a timely manner. This article will offer some important concepts and suggestions for creating your own œdisaster plan. It would be foolish to think that such a plan will never be needed. The only thing more foolish is not to have created a plan in advance.
Step One: Recognition and
Timely Response
Once a report is received, action should be taken to define and acknowledge the concern. Request clarification of the concern and its source: Is it coming from the owner, architect, engineer, consultant, general contractor, or construction manager? Is the concern a serious issue? Some-times a casual comment develops into a major problem (a cut on a finger turns into an amputated arm in the rumor mill). Let all concerned parties know your position immediately. If an investi-gation is required, request a meeting as soon as possible to discuss the problem and the investi-gation process. This gets you on the record as being responsive and begins to give you some control of the process.
Step Two: Fact Finding
Let™s use a simple example of how important it is to collect facts before diving into an inves-tigation. A number of years ago, while working for a ready mixed concrete supplier, I was called by a customer who was constructing a high-rise condominium project and told that we had low compressive strengths for concrete used for a slab pour from the previous month. This was a very large project that was closely monitored by our Technical Services Department. We had not even a hint of any low compressive strengths on any phase of the project prior to receiving this report.

I am frequently asked by contractors to aid in the selection of shotcrete equipment and acces-sories for many types of shotcrete applications, both wet-mix and dry-mix processes, including concrete repair and restoration, pool construction, mining, tunneling, soil nailing, slope stabilization, and refractory applications. There are many choices of equipment and acces-sories for shotcrete contractors today. Various types of equipment include concrete pumps, gunite (dry-mix shotcrete) machines, mixers, and predampeners. There are many more types of ancillary equipment and accessories that go along with the primary shotcrete equipment used today. Let™s take a look at some of these other tools used to apply shotcrete and why they are important.