Atterberg Limits Testing is just one of the testing methods that Encorus’s Civil Testing Group uses to determine properties of soil. According to ASTM International, Atterberg Testing Limits are six limits of consistency in soils that were defined by Albert Atterberg. These limits include the upper limit of viscous flow, the liquid limit, the sticky limit, the cohesion limit, the plastic limit, and the shrinkage limit. In modern engineering, the term Atterberg Limits commonly refers to only the liquid limit, the plastic limit, and in some cases, the shrinkage limit.
The liquid limit of soil is the minimum amount of water that would be added to a set amount of soil to change its consistency to a liquid state, meaning that the soil cannot retain its shape. The liquid limit of soils can be determined by creating a paste using soil and a small amount of water and putting it in a liquid limit device. The paste is separated into two halves using a grooving tool, and then allowed to flow together from the shocks caused by repeatedly dropping the device’s cup in a standard manner. This process is repeated with different amounts of water in the paste and the results are plotted on a graph to establish the liquid limit.
The plastic limit of soil is similar to the liquid limit, but it is the amount of moisture that causes soil to display plastic characteristics rather than liquid or solid ones. The plastic limit can be determined using a rolling method where the soil sample with a recorded amount of water is rolled into a 3.2 mm thread and broken into smaller and smaller pieces until it cannot be re-rolled and broken down any more. This process is done twice, and then the average water content of both trials is calculated to determine that soil’s plastic limit. The plasticity index of a particular type of soil can be found by determining the difference between the plastic limit and the liquid limit.
The shrinkage limit of soil is the maximum amount of water in soil that makes it saturated, but still in a solid state. When you add water to soil, the volume increases. However, when a soil sample reaches its shrinkage limit, the volume of the soil does not decrease when the amount of water is decreased even further. The shrinkage limit can be found in a soil sample by determining the relationship between initial wet mass, initial volume, the dry mass, and the volume after drying.
According to the ASTM International Designation: D4318–17E1 , “The liquid limit, plastic limit, and plasticity index of soils are also used extensively, either individually or together, with other soil properties to correlate with engineering behavior such as compressibility, hydraulic conductivity (permeability), compactibility, shrink-swell, and shear strength”. These testing methods are crucial when it comes to determining what type of soil to use as a foundation for construction projects. The properties mentioned above will affect the soil’s ability to maintain its durability under different forms of agitation. Therefore, it is essential for construction professionals to test the soil before starting construction to ensure the long-term integrity of the structure being built.
One of the in-house design services offered by Encorus Group is fire protection engineering. This discipline is relevant to almost any building design, since it helps to prevent fire and keep buildings safe in the event that a fire does occur. Fire Protection / Life Safety Specialist John Allan was able to share his knowledge and thoughts on the discipline.
Fire protection engineering, as defined by the Society of Fire Protection Engineers (SFPE), is the application of science and engineering principles to protect people and their environment from the destructive fire. It includes analysis of fire hazards, mitigation of fire damage through proper design, construction, arrangement, and use of buildings, materials, structures, industrial processes, and transportation systems. Fire protection engineering also includes the design, installation and maintenance of fire detection and suppression systems and communication systems, as well as post-fire investigation and analysis.
Fire protection engineering is becoming a design necessity by integrating the design process with other disciplines. All building codes provide the prescriptive requirements for fire protection, but not all building codes address every conceivable application. Encorus Group recognizes that there is more than the prescriptive approach to a design abnormality. Our experts use risk analysis and other tools to help clients find economic, effective solutions.
Encorus Group provides a wide range of design services for any occupancy and application a client may need. Our experience includes a wide range of fire alarm, fire suppression, and passive fire protection applications. One of the key factors that separate our designs from others is that we design for the serviceability of the system. We look beyond the minimal design requirements to envision how the system will serve the client, how is it expandable for future needs, and how can it be maintained and tested economically without being a burden to the owner.
Our fire protection design team is our whole company. Although we have dedicated fire protection and life safety staff, we pride ourselves on working closely with all disciplines to ensure the design is complete. Fire protection design is integrated into the “whole building” concept to ensure compliance with codes and standards. Fire protection must often interface with HVAC systems and electronic security systems. We do this up front to ensure full code compliance for the facility and to save the owner the cost and hassle of retrofitting missed requirements.
Encorus’s accomplishments and experience includes:
• Private Service Fire Water Distribution Systems
• Fire Pump House Design and Installation
• Large Water Tank Design for Fire Protection
• Fire Sprinkler Design (all types)
• Special Hazard Suppression and Detection Systems
• Fire Alarm Design (new and retrofit)
• Fire Alarm and Voice Mass Notification Systems
• Clean Agent Fire Suppression System Design
• Fire Hazard Analysis and Assessments (Risk Analysis)
• Forensic Fire Investigation
• Code Compliance Reviews
• Fire Safety Program Development
• NQA-1 Compliant Design
Encorus Group has an experienced fire protection engineering team of fire protection, mechanical, and electrical professionals ready to find better solutions to your toughest problems. If you require fire protection engineering services, please contact Encorus’s Director of Engineering Design, Tom Gilmartin, at 716-592-3980, ext. 124 or firstname.lastname@example.org.
For this week’s Fun Fact Friday, we will focus on one of the more technical aspects of engineering: drafting. Encorus Drafter Doug Acquard gave us some information about what drafting is and why it is important.
Drafting, also known as technical drawing, is the creation of accurate representations of objects, systems, or building structures for technical, architectural, or engineering purposes. Someone who is skilled in drafting is called a drafter, draftsman or draftsperson.
In drafting, objects are drawn to scale, and usually comprised of multiple views of the object or structure. They can be very detailed, and are often used for the construction or assembly of an object. For drafting systems, different colored lines represent a specific discipline, such as electrical, plumbing, HVAC, and structural. Though the lines are shown on architectural plans, they do not accurately represent to final product, but more as a guide for the contractor to utilize.
One might ask “why is this important, can’t I just tell a contractor what to do?” Without drafting, there would be no way to convey the same message to multiple bidders for a project, or accurately maintain a set budget. Drafting helps keep everything organized and projects on schedule.
Encorus Group has multiple experienced drafters on staff. If you require drafting services, please contact Drafting Manager Shannon Vrenna at email@example.com or (716) 592-3980 ext. 134.
Fun Fact Friday: Photo Edition
Did you know that wind turbines can be 300 to 400 feet tall and weigh up to about 350 tons? Encorus has had hands-on experience with wind turbines, providing Civil Testing services for the Arkwright Wind Farm! Learn more about Encorus’s larger-than-life Civil Testing experience here.
One of the environmental engineering services that Encorus Group offer is the creation of an SPCC Plan. Environmental Engineer Mary Padasak gave us some insight into what exactly SPCC Plans are and why they are important.
Spill Prevention, Control, and Countermeasure Plans (SPCC Plans) are documents created for facilities containing large reserves of oils, both petroleum and non-petroleum based. Their purpose is to protect navigable water and shorelines by helping prevent spill scenarios, and to provide roadmaps for cleanup and control of a spill should one occur. SPCC plans are required under federal law 40 CFR 112 for facilities that have greater than 1,320-gallon aboveground storage capacity or greater than 42,000-gallon completely buried underground storage capacity. Each SPCC Plan is unique to the facility and its contents. SPCC Plans include procedures to prevent spills during operations, control measures to be in place to prevent oils from entering the environment should a spill occur, and countermeasures to contain and clean up the spill, as well as mitigate any impacts to the environment. SPCC Plans must be certified by a Professional Engineer. They must also be reviewed annually and re-certified every five years.
New York State has requirements that go above the federal standard and are more protective of the environment. Under 6 NYCRR 613, tanks over 110 gallons, with some exceptions, must be registered to an owner who is responsible for their care and maintenance to prevent discharges to navigable waters. These registrations must be renewed every five years and are periodically audited by the NYS Department of Environmental Conservation. For underground tanks, trained operators are also required. These operators have been trained on the specific tank system they are using or registering, are knowledgeable in safe operation of the system, and know how to control, contain, and mitigate impacts should a spill occur.
Encorus Group has knowledgeable staff in the writing and review of SPCC Plans and tank registrations in New York State. Our professional engineers are able to certify the reports as required by federal law. We also have trained operators that can manage your underground tank systems and train your low-level operators. If you require an SPCC Plan, please contact Sheila Ransbottom, PE at (716) 592-3980 ext. 153 or email firstname.lastname@example.org.