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Moulton Laboratory Testing


Group B - Untreated
Group B - Treated / Uncured
Group B - Treated / Cured
Samples 1
Samples 2
Samples 3
Time = 0 hours 
Time = 18 hours
Time = 1008 hours
Color corrected photographs are taken to characterize the color of the samples before treatment, just after coating application, and after treatment curing. While the samples darkened substantially after treatment, this color shift diminished during the curing process.
In November 2018, the CAC began a testing program to evaluate the performance of treatments to improve the durability of the surface finishes. Optimal performance criteria for a treatment seeks to achieve the following:

1) Reduce susceptibility of paint layers to abrasion and biodeterioration

2) Not impact the color or matte lustre of the weathered extant finish unless the intent is to restore the weathered appearance to its original color (saturation)

3) reduce liquid water absorption, but not water vapor transmission

4) Satisfy environmental and personal health and safety standards

Due to the limited number of original samples, this testing program compared two types of treatments to provide Grand Teton National Park with options now and in the future.

  • Ethyl silicate consolidant (Prosoco OH100)
  • Ethyl silicate modified with silane (Prosoco H100).

The samples were divided into three cohorts of six sample coupons each. All the samples were exposed to accelerated weathering in a QUV Weatherometer.

Accelerated weathering is commonly employed to test the performance of a treatment under extreme simulated weather conditions. At intermittent stages during the testing program, the samples are characterized in terms of their color (by qualitative and quantitative means), resistance to abrasion, and hydrophobicity according to ASTM standards.

Based on the results of accelerated weathering and performance testing, a series of possible applications will be suggested which balance treatment potency with low aesthetic impact; these will be part of the outdoor pilot tests applied to the structure in Summer 2019.

filler block

Moisture test-1
 
moisture test-2
According to ASTM D7334-08, the relief of a water droplet applied to the surface indicates the ability of that material to resist water. The untreated sample (top) rapidly absorbed the water droplet, as inferred by the flat profile in the photograph. By contrast, the water droplet applied to a recently treated sample (bottom) stands high in profile, indicating that the coated surface is highly hydrophobic.

Red arrows indicate water droplets applied to two sample surfaces.


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