GCL internal strength

Questions and answers from the GMA Techline

GCL internal strength
In section 6.3.4 of Designing with Geosynthetics Fifth Edition, the internal shear reinforcement for a GCL is calculated using the geogrid veneer reinforcement method. This results in an internal reinforcement strength using kN/m.

Manufacturers of GCLs report their internal shear strengths in kPa. Do you consider these numbers: (1) equal to one other, (2) require a conversion, or (3) not related?

We would like our clients to undertake site-specific testing but would like to give them an indication of the type of reinforced GCL they might be looking at in the first instance.

(Andrea | Australia)

Andrea,
Nice question, which brings up the age-old concept of proper dimensionality, which always must be obeyed.

As you have intimated in option 2, you do not have proper dimensionality because the value of internal reinforcement strength in kN/m must be divided by the thickness of the GCL’s bentonite (about 4-5mm) to get stress units. Then it can be compared to internal shear strengths in kN/m² or kPa.

Bob Koerner | GMA Techline