Bulletin - United States, Office of Public Roads, Թողարկում 33-48U.S. Government Printing Office, 1908 |
From inside the book
Արդյունքներ 100–ի 1-ից 5-ը:
Էջ 8
... wear . This represents the percentage of material under 0.16 cm . ( inch ) in size , worn from 5 kilograms of a sample made up of fragments ranging in size from 1.5 to 3 inches in their greatest diameters . The material is raded in a ...
... wear . This represents the percentage of material under 0.16 cm . ( inch ) in size , worn from 5 kilograms of a sample made up of fragments ranging in size from 1.5 to 3 inches in their greatest diameters . The material is raded in a ...
Էջ 11
... wear and tear of traffic , it can be seen that the presence of this prop- erty is most essential to good results ... wearing qualities , are influenced in an important manner by the character and the amount of the secondary or altera ...
... wear and tear of traffic , it can be seen that the presence of this prop- erty is most essential to good results ... wearing qualities , are influenced in an important manner by the character and the amount of the secondary or altera ...
Էջ 12
... wear , and by good cementing values . Rocks of this general type differ considerably among them- selves in road - making value , but almost all of them are superior to the best rocks of other types . The tests also show that a slight ...
... wear , and by good cementing values . Rocks of this general type differ considerably among them- selves in road - making value , but almost all of them are superior to the best rocks of other types . The tests also show that a slight ...
Էջ 13
... wearing quality is due in part to the fineness of the grain , the texture , and the hardness of the minerals , and ... wear . In southern and eastern Maine trappean rocks are present in abundance only in the Penobscot Bay region and in ...
... wearing quality is due in part to the fineness of the grain , the texture , and the hardness of the minerals , and ... wear . In southern and eastern Maine trappean rocks are present in abundance only in the Penobscot Bay region and in ...
Էջ 14
... wear is moderately low , though higher than for most trap rocks . Their hardness is nearly the same as in the traps ... wearing qualities are 14 ROAD MATERIALS OF SOUTHERN AND EASTERN MAINE .
... wear is moderately low , though higher than for most trap rocks . Their hardness is nearly the same as in the traps ... wearing qualities are 14 ROAD MATERIALS OF SOUTHERN AND EASTERN MAINE .
Common terms and phrases
Agriculture amount applied Approxi asphaltic Average cost barium chromate binding bitumen bridge built calcium chloride cementing value cent improved chemical clay coal coal tar coating concrete corrosion cost per mile counties report crude crushed cubic centimeter culverts depth determined diabase diameter diorite distillation Dollars dust preventives earth roads emulsions engineer feet feldspar foundation grams granite gravel gravel roads heated highway hornblende hydrometer igneous rocks improved roads inches iron Kind of stone limestone Location macadam macadam roads mate percentage metal method Mileage of improved mineral composition obtained Office of Public paraffin percentage of roads pigments plagioclase PLATE present public roads quarry quartzite Railroad facilities residue rhyolite road materials available road surface roads improved sample sand sand-clay roads schists Section solution spans specific gravity square yard steel Table tars temperature tion total mileage town traffic U. S. Dept Washington weight zinc
Սիրված հատվածներ
Էջ 19 - The crucible and both flasks are then dried at 125° C. and weighed. The filtrate containing the bitumen is evaporated, the bituminous residue burned, and the weight of the ash thus obtained added to that of the residue in the two flasks and the crucible. The sum of these weights deducted from the weight of substance taken gives the weight of bitumen extracted.
Էջ 5 - And whenever the commission shall be of opinion, after a hearing, had upon its own motion or upon complaint...
Էջ 17 - The most widely used method of making the total bitumen determination consists in dissolving the bitumen in carbon disulphide and recovering any insoluble matter by filtering the solution through an asbestos felt. The form of Gooch crucible best adapted for the determination is 4.4 centimeters wide at the top, tapering to 3.6 centimeters at the bottom, and is 2.5 centimeters deep.
Էջ 20 - ... flask. If difficulty is still experienced in dissolving the material, a rounded glass rod will be found convenient for breaking up the undissolved particles. Not more than one-half of the total amount of naphtha required should be used until the sample is entirely broken up. The balance of the 100...
Էջ 3 - The stopper is then inserted in the tube and the cup filled with water at 25 °C. to the top of the projections. The measuring cylinder should be placed directly under the outflow tube so that the material, upon flowing out, will not touch the sides, and the stopper may then be removed. The time required...
Էջ 27 - The residue is poured into an 11-cm. porcelain evaporating dish and evaporated on a steam bath. The most scrupulous care must be taken at all times that no flames are in its immediate vicinity. Evaporation is carried on at a gentle heat, with continual stirring, until foaming practically ceases. It is advisable to have a large watch glass at hand to smother the flames quickly should the material ignite. As the foaming subsides, the heat of the steam bath may be gradually raised, and evaporation...
Էջ 18 - The crucible is filled with the suspended asbestos, which is allowed to settle for a few moments. A light suction is then applied to draw off all the water and leave a firm mat of asbestos in the crucible. More of the suspended material is added, and the operation is repeated until the felt is...
Էջ 5 - ... to any desired temperature at which the test is to be made. This temperature should be accurately maintained, and should at no time throughout the entire test be allowed to vary more than one-half a degree Centigrade from the temperature selected.
Էջ 7 - Binding power is thus, probably, the most important property to be sought for in a road-building rock, as its presence is always necessary for the best results. The hardness and toughness of the binder surface more than of the rock itself represents the hardness and toughness of the road, for if the weight of traffic is sufficient to destroy the bond of cementation of the surface, the stones below are soon loosened and forced out of place. When there is an absence of binding material, which often...