During geomembrane installation, most CQA plans include third party destructive seam testing to assure the quality of the welds. HDPE or LLDPE Samples that are received at the Lab by noon will be reported same day via email. Other types of material seams can be tested but may not be reported same day due to special conditioning requirements. TRI also provides seam forensic capabilities to assist the project if and when any problems are encountered with dirty seams or welds marked by too much or insufficient heat, bad alignment, etc. We can use microtomes and photographs of observations to assist clients in responding appropriately to any quality assurance issue.

High strength geosynthetic reinforcement products are often specified and it is important to confirm the characteristic high strength of these products. TRI is the highest quality laboratory in this regard as we employ a variety of state-of-the-art tension testing clamps and measurement systems. Included in this inventory of responsive tension testing technologies is the use of “Smart”-clamps, able to adjust gripping pressure based on the measured tension strength. These clamps adjust during testing to maximize the gripping pressure without damaging the material tested. Working together with non contact extensometry for strain measurement, TRI is able to test the strongest geosynthetic materials in the world. TRI also tests high strength component yarns and tapes, and high strength geosynthetic stitched and mechanical seams.

TRI performs creep/stress rupture testing for characterization of reinforcement geosynthetics:

• strain limit creep testing
• stress rupture limit testing
• development of reduction factors for creep/stress rupture (RFCR)
• accelerated creep and stress rupture testing using conventional time temperature superposition (TTS)
• accelerated creep and stress rupture testing using TRI developed Stepped Isothermal Method (SIM) testing

TRI also performs compression testing to measure normal-to-the-plane deformations of geosynthetic:

• Drains and/or liner systems
• Short and long term compressive strength of geosynthetic drains
• Short and long term compressive strength of geosynthetic liner systems
• Strain (deformation) measurements within liner systems
• Compression creep via conventional accelerated time temperature superposition (TTS)
• Compression creep via TRI developed Stepped Isothermal Method (SIM) testing

The durability of geosynthetics and geosynthetic systems is often measured to ensure long-term performance. TRI is a world-wide leader in durability testing and offers considerable capabilities to meet regulatory-driven or product development needs. TRI responds to both environmental and load/construction durability concerns via large-scale and bench-scale testing of geosynthetics and their component materials. Some of the durability testing services and relevant standards are listed below.

TRI has broad capability to evaluate the microstructural properties of geosynthetic materials. This capacity, in concert with our performance testing capability, is often employed to investigate the cause for geosynthetic seam problems or geosynthetic material failures. Senior technical staff bring their experience to bear on specific technical challenges encountered as geosynthetic materials are installed. Forensic investigation is also called upon when new and/or unknown materials are evaluated, or where premature field failures have occurred. TRI employs a variety of equipment to support forensic evaluations including a full service DuPont thermal analysis testing system (TGA, DSC, DMA, TMA) as well as analytical equipment (FTIR, GC/GCMS).

While traditional quality assurance programs have involved on-site sampling of product rolls after they arrive, they often resulted in expensive delays and costly corrections when subsequent testing identifies non-conforming product rolls. TRI has revolutionized this approach by establishing in-plant manufacturing quality assurance (MQA) inspection and sampling services.

Almost all TRI’s in-plant services are established in the host-city of the manufacturer of interest, thus eliminating the need for clients to pay for travel and lodging costs traditionally associated with MQA inspection and sampling events. TRI may secure samples from the manufacturing plant, ship to our laboratories and test in accordance with the CQA plan. The previously unaffordable is now financially feasible and of significant benefit.

Other plants by special arrangement

TRI’s state of the art interface friction laboratory features 20 large scale direct shear boxes. Our loading capacity ranges from 50 to 40000 lb/ft2 (2-1900 kPa). Our in-house manufactured low load shear boxes provide our clients with improved testing and repeatability of interface shear strengths under cap and construction loading conditions (50-1000 lb/ft2, 2-50 kPa). Continued research in GCL hydration and consolidation, gripping and clamping systems ensures that TRI is the industry leader in interface friction testing.

TRI performs Interface Friction/Direct Shear testing to investigate slope stability:

• geosynthetic-geosynthetic interfaces
• soil-geosynthetic interfaces
• internal GCL shear and GCL interfaces
• large-scale soil shear strength
• long-term creep at the interface
• constant load or constant strain testing

TRI performs road base and asphalt reinforcement testing to characterize the improved performance of geosynthetic systems over traditional non-geosynthetic systems.

• Bench scale static and dynamic loading of reinforced road base structures
• Bench scale static and dynamic loading of reinforced asphalt structures
• Asphalt retention testing
• Confinement testing of geosynthetic reinforcement in road base courses

TRI performs clogging potential for long-term filtration applications

• gradient ratio
• long-term hydraulic conductivity
• long-term residual flow

TRI performs installation damage testing services to characterize the construction damage imparted to a geosynthetic as a function of installation. TRI has adopted a convenient method for applying installation damage to geosynthetics that allows for exhumation of the test samples while avoiding unintended damage. The method was developed and reported by Watts and Brady (1994) of the Transport Research Laboratory in the United Kingdom. TRI uses this procedure as modified to generally conform to ASTM D5818 requirements.

The following construction quality control measurements are followed during exposure:

• Sieve analyses, as well as Proctor density and Attenberg limits analyses, as applicable, are performed on each soil/aggregate
• Lift thickness measurements are made after soil/aggregate compaction
• Moisture and density measurements are made on each lift using a nuclear density gage to confirm that densities >90% of modified Proctor (per ASTM D1557) were being achieved
• Each geosynthetic is exposed to soils/aggregates chosen by the client from a range of available TRI maintained stockpiles having different gradations and representing fine grain sands to large angular gravels. Detailed particle size distribution curves and pictures are available for review

TRI performs connection and pull-out testing services to support the design of geosynthetic reinforced walls and slopes.

• MASONRY BLOCK connection and shear testing
• Constant strain or constant load testing
• Ceep/stress rupture at the connection
• RFCR of mechanical and friction connections