How to Determine the Temperature of Freshly Mixed Hydraulic-Cement Concrete and Why it is Important

How to Determine the Temperature of Freshly Mixed Hydraulic-Cement Concrete and Why it is Important

In the civil materials testing industry, there are several testing methods that can be applied at construction sites. This article will focus on the testing method that is used to determine the temperature of freshly mixed hydraulic-cement concrete. There are time-dependent requirements for the temperature of concrete that is being used in new construction. In testing the temperature of the concrete, it is ensured that the material will meet these requirements so that it can solidify in a given period of time and can be used safely in construction.

This testing process involves a container, temperature measuring device, and partial immersion liquid in glass thermometers. According to the ASTM standard for the testing method for the temperature of freshly mixed hydraulic-cement concrete, the temperature measuring device should be placed about 3 inches deep into the fresh concrete. After a period of time between 2 and 5 minutes has passed, the temperature measuring device should be removed and the temperature should be recorded. The recorded results from the test are then charted and compared to the appropriate standard specification for freshly mixed concrete to determine if it is safe to use in construction depending on the project’s time constraints.

If the concrete is determined to be too cold or too warm, the variation in temperature affects the rate at which the concrete sets up or solidifies. When the temperature of the material is known, the contractor utilizing the concrete will know how long the concrete will take to set so that they can safely and effectively plan the finishing processes for the project.

By testing the temperature of freshly mixed hydraulic-cement concrete, it is assured that the pre-determined standards are being met, resulting in the safety and longevity of the structure. It can also result in saving time and money, as the construction schedule and budget are among the most important things that can be adhered to throughout the project. Civil materials testing gives the construction project manager peace of mind as they work to meet their own budget and deadline restraints. Encorus’s Civil Testing Group performs testing for determining the temperature of freshly mixed concrete, as well as other concrete testing services, both in the laboratory and in the field.

If you have a need for determining the temperature of freshly mixed hydraulic-cement concrete or any other civil materials testing service, reach out to Civil Laboratory Supervisor Jeremy Lake at (716) 592-3980 ext. 133, or jlake@encorus.com.

How Cold Weather Impacts the Structural Integrity of Concrete

How Cold Weather Impacts the Structural Integrity of Concrete

As a Western New York-based firm, we are no strangers to cold weather. The temperature has a daily impact on our lives, from what clothes we wear to how long our morning commute will take. Just as the temperature has an impact on us, it also has an impact on construction materials, specifically concrete. Exposure to extreme temperature lows can have adverse effects on the structural integrity of concrete.

The temperature should be controlled throughout both the concrete mixing and placement processes. Temperature control during these phases prevents thermal contraction and shrinkage later on in the concrete’s lifespan. According to the ACI 306R-88 standard, exposure to extreme cold during placement can cause rapid moisture loss from warm concrete heating the surrounding cold air, resulting in a reduction of relative humidity. The decline of water content in the concrete can lead to extended setting periods and variation in concrete strength, which could have detrimental effects on the schedule, budget, and safety of the construction project.

Fortunately, practices and procedures have been developed to protect the concrete from being damaged or structurally compromised as a result of freezing. According to the American Concrete Institute (ACI) Cold Weather Concreting (ACI 306R-88) standard, the goal of these cold weather preventative practices are as follows:

“Prevent damage to concrete due to freezing at early ages,… assure that the concrete develops the required strength for safe removal of forms, for safe removal of shores and reshores, and for safe loading of the structure during and after construction,… maintain curing conditions that foster normal strength development without using excessive heat and without causing critical saturation of the concrete at the end of the protection period,… limit rapid temperature changes, particularly before the concrete has developed sufficient strength to withstand induced thermal stresses,… [and to] provide protection consistent with the intended serviceability of the structure”

As listed in the ACI 306R-88 standard, the methods of protecting new concrete include covering the concrete with insulating materials, creating an enclosure surrounding the concrete, using embedded thermal coils to heat the concrete internally, covering the placed concrete with tarps, and implementing insulated forms during the setting period.

Just as preventative measures are necessary to protect the concrete during the construction process, it is also necessary to make sure that the protection methods were effective, which can be achieved through materials testing. Compressive strength is one of the indicators to determine if the concrete meets structural and safety standards. This test is performed by applying an increasing amount of pressure to a piece of material to determine how much weight it can handle before fracturing. Depending on the purpose of the concrete (flooring, foundation, structural support, etc.), there are different standards of pressure that the material is expected to withstand to be considered fit to support the intended load. Encorus’s Civil Testing Group performs laboratory compressive strength testing for a variety of construction materials, including concrete core samples.

If you have a need for concrete testing or have any questions about the impacts of temperature on the structural integrity of concrete, contact Civil Laboratory Supervisor Jeremy Lake at (716) 592-3980 ext. 133 or jlake@encorus.com.

Why Concrete Testing is Essential for New Construction Projects

Why Concrete Testing is Essential for New Construction Projects

Concrete is one of the most common materials that is used in construction as the building blocks for the foundations of various structures around the world. These structures could be as large and complex as your office high-rise or as simple as the sidewalk that you use every day. Regardless of the size or use, it is of the utmost importance that the concrete has been tested by a qualified civil materials testing company. It can be argued that there are three main requirements when it comes to construction projects: efficiency, functionality, and safety. Concrete testing plays a major part in each of these three aspects.

As detailed in Encorus’s previous Fun Fact Friday article, civil materials testing is financially invaluable when it comes to construction projects of any size. Most flaws in concrete can be corrected within the a certain time frame and budget if they are identified early on. This allows the construction team to maintain the client-set standards for finances and scheduling, thus creating a high level of efficiency. If you are interested in learning more about how civil materials testing maximizes construction schedules and budgets, click here.

Functionality gives each construction project meaning and defines the intended purpose of the structure. If a slab of concrete is intended to be used as flooring, it should be evaluated to make sure that it can support the load and traffic that it will be subject to post-construction. In testing the concrete to make sure it can fulfill its intended purpose, it guarantees the functionality of the structure.

Public safety is one of the top priorities in the construction of any given project. It is important to test concrete structures to ensure that they are safe in regards to load-bearing, stability, and any other factors that could come into play. If concrete is being used to support a bridge, civil materials technicians test the strength of that concrete to make certain that it will not put the safety of the public on the line by cracking, crumbling, or failing in any other way.

Encorus’s concrete services include concrete field inspections, compressive strength testing, and concrete mix design verifications. If you have any questions about or need for concrete testing, contact Encorus’s Civil Laboratory Supervisor, Jeremy Lake, at (716) 592-3980 ext. 133, or jlake@encorus.com.

How Civil Materials Testing Maximizes Construction Schedules and Budgets

How Civil Materials Testing Maximizes Construction Schedules and Budgets

New construction developments are often considered to be high stake projects that require adherence to strict budgets and timelines over the course of the construction period. This creates a necessity for producing high quality work while maintaining budget and scheduling requirements.

The construction industry produces heavy pressures to complete work within the given time and budget, and project managers are expected to take measures to ensure that the work will be satisfactorily completed according to predetermined client standards. If there is an unidentified issue with the site or the materials being used, it will likely lead to a waste of time and expenses. This waste is unnecessary and can be avoided by testing the materials for flaws before or during the construction process.

Having the materials tested by a qualified technician beforehand is a preventative process that is timelier and more financially efficient than if any flaws were to go undetected, and then found at a later time, which would lead to backtracking in the project and the unwarranted expenditure of time, money, and materials.

If a flaw is detected by a qualified technician in the early stages of construction, the faulty material can be quickly replaced without the need to undo any other completed construction work. The cost of hiring a civil materials technician is a fraction of the time and financial cost of faulty materials, especially if it goes unnoticed in the long run, which would produce a dangerous structure that would put public safety in jeopardy.

Civil Materials Testing services offered by Encorus in the field include concrete inspections, floor flatness testing, in-place density testing, fireproofing / firestopping inspections, certified welding inspections, ICC special inspections, asphalt testing, wood framing inspection, EIFS inspections, masonry inspection, structural steel inspection, and anchor bolt pull testing.

Encorus also offers a variety of laboratory testing, including compressive strength testing, concrete mix design verifications, grain size analysis, Atterberg Limits Testing, hydrometer analysis, asphalt testing, USCS soils classification, specific gravity testing, and standard / modified proctors.

If you have any questions about how to maximize your construction schedule and budget or require civil materials testing services, contact Encorus’s Civil Laboratory Supervisor, Jeremy Lake, at (716) 592-3980 ext. 133, or jlake@encorus.com.