Test Results

The following table presents a few physical properties of Thastyron and the RASTRA® wall and is based upon material tests conducted.

TESTING OF PHYSICAL PROPERTIES

Parameter	Rating/Value	Remarks
Recycled Content	± 85% by volume	Mainly postconsumer expanded polystyrene.
Bulk density	22 lbs/ft3 ± 10%	Elements for specific applications may be produced with higher density.
Compressive strength of THASTYRON	56 psi	Depending on density.
Tensile strength of THASTYRON	43 psi	Depending on density.
Water vapor transmission	6.1 / inch	This is a (dimensionless) factor to measure possibility of condensation in the wall, particularly in cooler periods or with high air conditioning; the low value of Thastyron is a guarantee that no condensation will occur.
Fire endurance	4 hours rating (ASTM E119)	A 10" unplastered RASTRA® wall has been tested for 5 hours under a load of 10,000 lbs/lin.ft.; two tests have been performed with an additional positive and negative load perpendicular to the wall, simulating a 35 mph wind pressure; with a temperature in excess of 2000°F on the exposed side the surface temperature on the unexposed side of the wall did not increase for more than 7°F; a high pressure water stream directed towards the wall immediately after burning did not penetrate the wall.
Thermal barrier (Room fire test)	no flame spread, no smoke development, wall meets UBC 26-3	A wood crib is burned in a corner built with unplastered RASTRA® walls exposing it to appr. 1700°F; flame spread, smoke and any damage of the wall is monitored.
Surface burning characteristic	flame spread index 0 smoke development index 5 NFPA class A UBC class 1 ASTM E 84 (NFPA 255, UBC 8-1)	4" thick Thastyron panels were exposed to flame. Spreading of the flame front and smoke density ,compared to red oak, was measured. The flame front was proceeding less than 0.5ft, which is within the flame spread of the burner. For smoke development light absorption is measured. The test showed some very low absorption, for a test result values are always rounded to the next figure divisible by 5.
Frost resistance	highly frost resistant	Thastyron specimens have been soaked in boiling water and frozen at -4°F; after 50 cycles no reduction of compressive strength was found.
Toxicity	low toxic	Testing conducted using Leaching Procedure by EPA SW-846 method 1311, metals by method 6010 & 7470, volatiles by method 8240; metals are less than 1/20 of regulatory limit, only traces of 4 volatiles out of 40 tested found.
Formation of mildew	mildew & fungus growth is not anticipated	Test cubes were kept under moist conditions for 40 days after inoculation of test germs (aspergillus niger, rhizopus nigricans). No growth of cultures could be observed; formation of mycel or konidien culture did not take place.
Water transmission	meets requirements ASTM E331, ASTM E514, meets UBC 14-1 (grade "C" craft paper)	10" thick RASTRA® wall with skim coat has been exposed to a water spray with a minimum flow rate of 5.0 US gal/ft2.hr at a differential pressure to simulate a 125mph. (Extended time testing has been done by US Navy and met standards).
Average wall humidity	average 2.5% by volume	Samples have been taken from a home more than 5 years in use from areas where most humidity is expected.
Expansion	0.0018inch/ft (as standard concrete)	Even as RASTRA® elements without concrete grout show shrinking and swelling in changing humidity, shrinkage is neglectible once the concrete is poured.
Thermal performance	dynamic R-values 20 to 49 h.°F.sqft/Btu (click here for more details)	European testing on a 5ft by 5ft, and US testing of 8ft by 8ft walls revealed heat conductivities of 0.084 to 0.053 Btu/h.°F.ft of dry, grouted 10", 12" and 14" walls. DBMS values between 1.79 and 2.17 have been established for 6 US climate zones. Energy usage shows even better efficiency.
Sound insulation	>50dB(a)	Measurements have been taken in laboratories and in real buildings; dB is a value measured on a logarithmic scale, therefore, f.i. the difference between 27dB (a good value for a 2x6 framed wall) and a 50dB RASTRA® wall result in a 199 times lower sound intensity. The value indicated in test results is an average measure on a band width of 100 to 3150 Hz. Another aspect is sound absorption which a RASTRA® wall provides.

TESTING OF STRUCTURAL PARAMETERS

Parameter	Rating/Value	Remarks
Pillar strength	> 70 kips/lin.ft (failure load)	Tested was a pillar consisting of 1 RASTRA® std. Element capped with 2 end elements; concrete strength 3000psi, no reinforcement.
Cyclic shear	10ft x 10ft: ±68 kips 5ft x 10ft high: ±20 kips	Walls have been constructed with reinforcement on 15" centers not centered in the cavity. In order to simulate high wind or earthquake loads cyclic loading in plane and a constant axial load of 10000 plf has been applied. The wall showed extreme good ductility and a deflection of 1.14" re. 1.24". Failure occurred near the base connection to the foundation.
Cyclic narrow shear wall	30" x 10ft high load at 60": 11kips load at 75": 10kips load at 90": 9kips	To investigate shear resistance on very short elements of a wall specimen consisting of only 1 std and 2 end elements have been tested. Boundary reinforcement has been increased to avoid premature failure due to flexural forces. A constant axial load of 10000plf has been used. Shear load has been applied in 3 heights to gain information about pillars with different aspect ratios.
Slender wall	axial load 1000plf, 7.5" out of center, width 45" (4 col.) flexural load at failure: wall 16ft high: 2800lbs wall 20ft high: 2200lbs	The specimens were loaded with a constant out-of-center load to simulate roof loads introduced by ledgers. The out-of-plane load was applied on 1/3^rd points on the side to increase the eccentricity of all loads. The walls were able to sustain the applied axial and out-of-plane loads through the deflection limits given in the codes and beyond.
Out of plane load	9ft span: 9kips	Load was applied in 1/3^rd points on a 10" RASTRA® element laying flat. No brittle failure occurred even as test was continued beyond 80% peak load . Deflections at peak load were 2.44".
Lintels & beams	height:1 element (2 pillars) 10ft span: 21kips 5ft span: 26kips	One RASTRA® element was used capped on the lower side with an end element to simulate a lintel design as it may be used in the field. Support was free at 10ft distance, loaded at 1/3^rd points.

The outline of test results above are for rough reference only. For any application of these tests for structural calculation, request the full text of these reports or ask for engineering information based on such testing.

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Last modified: August 22, 2003
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