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Show MOTOR TRUCKS AND ROADS j Preliminary road impact tests made bv the bureau of public romls indicate that the impact pressure exerted by a motor truck in motion is about six times that of a truck at rest. Tho tfsts were conducted with a rl.-tss B government truck loaded up to five tons. runniuK up to fifteen miles an hour and allowed to fall fr-Tii varying height p on the impact measuring apparatus. These tests will be co n t i n u ed w i t h t ru ck s rn n ci ncf from the lightest weight to the heaviest until complete data is obtained. The rpiestion of the relative impact exerted by trucks with Solid versus (riant pneumatic tires will also he investigated. Definite arrangements have been made to srn-ure a Packard three-ton truck with requisite tire equipment for these tests and a loan of other units would be welcomed wel-comed by the government officials. Tests to al:ow the resistance of vari- ous types of ruad surface such as con- J ( crete, asphalt, etc., are soon to be tinder- J taken. About fifly road slabs built of these materials will be broken under the I impact of a machine which approximates the impact effect delivered by motor trucks. By measuring the amount of impart actually delivered by the motor trucks to roads and by proceeding further in I test I tic the d'-striu'tion of actual road slabs subjected to impact, government of- j fioials hope to obtain very definite In- j formation which will permit them to de- i sign a high type pavement rapahle of re- sistlng definite traffic conditions. i |