artificial lawn average of five samples

artificial lawn average of five samples

Calculation artificial lawn5 samples the arithmetic mean, according to formula (R1) Total grate deviation rate:
(1) the formula. D_ deviation, F uniformly arithmetic mean of five samples, in units of Newtons (N);
F-sample extraction force, in Newtons (N);
If a deviation of the test results of the sample more than 30% of the sample test result is invalid, retest.
Annex C (normative) Determination of the coefficient of friction - sneakers France
A range
The method used in the laboratory or in the field Cao, test a variety of conditions with artificial lawn sports shoes and the coefficient of friction differential between the imagination.
2 Definitions
Frictional coefficient
Move the desired level sneakers pull Bao weight of the shoe and shoes which are subject to heavy pressure and mass ratios obtained. According to equation (1) calculated as follows:
(1) where:
ST-Friction coefficient:
F-moving force required level sports shoes, in F is just starts moving force of the shoe, in units of Newtons (N);
G-quality shoes and shoes are exposed mass of the weight and power of the doorpost obtained, in kilograms (kg).
2 friction coefficient difference
Coefficient of friction in different directions in several directions and the measured friction coefficient arithmetic mean of the absolute deviation.
3 Test Equipment
A shoe as a national standard 26 yards shoes, soles of rubber, sole thickness is 24, and flattened on the shoes.
Nylon band width of 2 24nn, a length of 1830.
3 barbell weight .34 kg, diameter 29c, 1c each side sticky thick vinyl foam.
4 Test Procedure