| 摘要 |
Fillers for masses based on bitumen and/or tar, esp. for the surfacing of roads, consist of powdered stones or their mixt. The filler contains by wt. 1-15% of expanded perlite which is milled. The filler pref. contains 2-7% perlite and may also contain (a) a cationic surfactant and/or (b) 10% max. of hydrated lim; and/or (c) rubber, which is opt. reticular. The filler has properties equal to or exceeding those of conventional fillers, while being less expensive, easy to work, and contg. no materials which are harmful to health such as asbestos. Road su rface coatings of fine concrete with asphalt can be obtd. with voids below 1%, using a ratio filler:bitumen of 65:35, corresp. to 6.5% bitumen and 12% filler in the asphalt-concrete mixt. |
