We believe technical experience is vital to the specialized services we offer and our geotechnical professionals deliver years of experience that includes diverse and challenging geotechnical projects. Our clients include school boards, universities, industries, contractors, developers, healthcare providers, private corporations, non-profit organizations, state highway departments, and other state and federal agencies. We are passionate about assisting our clients in implementing cost-effective quality assurance programs for construction and developing cost-saving approaches to challenges posed by site conditions and geotechnical constraints.
Transmission Line and Substation Services
TTL personnel have extensive experience with the unique engineering challenges associated with Transmission Line and Substation design and construction. In the past 5 years, TTL has provided engineering services for more than 200 substations (138 kV to 500 kV) and more than 400 Transmission Lines (69 kV to 345 kV) with routes ranging from 35 miles to 200 miles.
TTL’s in-house drilling team is safety-conscious, licensed, well-trained, and consists of a ﬂeet of drilling equipment including all-terrain and truck-mounted drilling equipment capable of performing hollow-stem, mud-rotary, air-rotary, ﬂight-auger and rock-coring drilling methods. TTL has extensive experience performing subsurface investigations in marine environments and rocky terrain. Our team is trained and highly experienced with in-situ tests such as CPT and pressuremeter tests. Our clients have transmission lines and substations across more than half of the United States.
Our Transmission Line and Substation services include:
- Civil Site Design
- Survey Services that include Topographic, Boundary, Alignment/Route Planning, Construction Staking, As-Build, UAV Aerial Photography
- Foundation Designs of Transmission Line Structures
- Environmental Consulting
- Construction Observation, Testing, and Inspection
- Construction Materials Testing services
- Bid phase services
TTL provides our clients with high-quality assistance in obtaining reliable subsurface data. We maintain our own in-house fleet of truck-mounted and all-terrain drilling rigs. TTL’s drill crews are experienced in hollow-stem auger drilling, rotary drilling, and wire-line core drilling. We specialize in the construction and installation of piezometers, monitoring wells, multi-cased wells and large-diameter recovery wells. We also provide soil sample collection using direct push methods to minimize investigation-derived wastes. Our crews have experience with drilling requirements for underground storage tank assessments, landfill evaluations, industrial sites, sludge ponds, and many other settings. TTL has state-of-the-art equipment to provide our clients with the most efficient and cost-effective technologies available today. Our drilling personnel are trained in accordance with 29CFR 1910.120 and are qualified to drill in Level D, C, and B personal protective equipment.
Once we have evaluated the samples gained from the site exploration, we can then recommend appropriate types of foundations (shallow, deep, pile, pier, etc.) for the type of structure planned for that site.
Soils can change under the load of foundation structures. The total vertical displacement occurring at foundation level is known as settlement. The cause of foundation settlement can be attributed to changes in the soil for a variety of reasons. We perform tests and provide consulting to help our clients determine the root causes when settlements occur.
The International Building Code (IBC) that has been adopted by most local governing bodies requires the structural designer to assign a site class (A through F) to every building project. The seismic site class depends on the soil and rock conditions within 100 feet below the site. The site class is most often evaluated using data from soil borings, but the IBC places conservative limits on site class when using boring data. That conservatism can have a significant impact on the structural and mechanical systems used during building construction. The IBC allows evaluation of seismic site class on the basis of the measured or estimated shear wave velocity profile below the site and that method is not subject to the same conservative limits applied to boring data. Measuring the shear wave velocity profile at the site can sometimes improve the seismic site class compared to what boring data may indicate, which can result in a more economical structural and mechanical design and allow an owner to realize a substantial saving in construction costs. TTL uses a geophysical method that does not require drilling or sampling to quickly and cost-effectively measure the shear wave velocity profile below a site. Our extensive experience with these analyses allows us to quickly produce results which most often allow the maximum reduction in seismic parameters.
Forensics is the exploration of materials, products, structures, or components of a structure that have failed or do not operate as intended. Signs of failure include doors not closing properly, drywall cracks, or even an entire building beginning to slope. Generally, the purpose of a forensic engineering exploration is to locate the cause or causes of failure with a plan to improve performance or life of a component or, in some cases, assist a court in determining the facts of an accident. TTL’s team approaches every forensic project with a thorough understanding of the various causes of damage or settlement and is skilled in making recommendations and working with our clients to address those issues.