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Show ; LOADS' CONSTRUCTION OF GOOD ROAC Concrete Highway Is Composed of Mixture of Sand, Stone, Portland Cement and Water. The concrete road is composed oi a carefully proportioned mixture oi clean, hard, well-grnded sand, pebbles peb-bles or broken stone, Portland cement end water. This mixture is laid upon the subgrade to n depth of 7 inches or more for the entire width of the road, and soon hardens into a mass as hard as rock. The materials are bonded together by the cement so firmly firm-ly that it is impossible for traffic to loosen or separate the particles. For this reason no expensive maintenance is required. The foundation or subgrade is compacted com-pacted where the concrete is to be laid and the roadbed is drained so that no water will remain under the slab, writes A. L. Pettibone in Dakota Farmer. Upon the foundation concrete con-crete is laid in one or two courses. A one-course concrete road consists of a relatively rich concrete mixture throughout. A two-course road consists con-sists of a somewhat leaner mixture for a base with a rjher top or wearing course, applied before the concrete in the base has begun to harden. Frequently Fre-quently re-enforcement in the form of wire fabric or steel rods is embedded in the concrete. This assists to prevent pre-vent cracks in the slab and aids in keeping cracks which may form from opening to any appreciable extent. The high wearing quality of the concrete con-crete road results from using properly graded, clean, hard sand and pebbles or crushed rock. These must be combined com-bined with Portland cement in carefully care-fully measured proportions, mixed with a power-operated batch mixer to produce pro-duce a stiff plastic consistency, then placed upon the foundation and struck off with a template or strike board, so shaped that the surface of the pavement pave-ment will have the desired crown. After Af-ter rolling with a light, metal roller to compact the concrete and remove excess water used in mixing, the concrete con-crete is finished by seesawing a section sec-tion of rubber or canvas belting along 4 spi An Improved Highway in West. the pavement, leaving a true, even, gritty, dense surface. 'When sufficiently sufficient-ly hardened to prevent pitting or marking, the surface is sprinkled with water, then covered with 2 inches or more of moist sand or earth, which is kept wet by sprinkling for from ten clays to two weeks to prevent the concrete con-crete from drying out tco rapidly. Under Un-der no. circumstances should a concrete con-crete road be put in use until it is 14 days old and in cool weather a longer time is necessary. This is a brief summary sum-mary of the essentials of the construction construc-tion of a concrete road. GOOD ROADS ARE PROFITABLE Authorities Should Act to Meet Growing Grow-ing Demands Before Trade Goes Other Ways. Good roads are a paying investment. Local authorities in cities, towns and counties should act without delay to meet the growing national and local demands before trade goes in other directions. It is almost impossible to get back the lost advantage after other oth-er districts have won it. NOT AFFECTED BY WEATHER Heat or Cold, Freezing and Thawing Does Not Injure Concrete Once It Is Hardened. Concrete roads are not affected by heat or cold nor by freezing or thawing thaw-ing when it is once hardened. Other materials tracked upon concrete have no effect upon it. Heat does not soften the binder permitting it to flow; cold does not make it brittle, causing it to chip. Proper Grade of Road. J The grade of the road is important, for on this depends the weight of the load which can be hauled economically. Improvement in Texas. Texas this year will spend a total of $7f,J1 (5.000 on improved highways, according ac-cording to figures compiled by the state highway department. Eialirg Roads Is Important. ! Tli imHiVng of good roads is of the jwr.' rt importance to a ovmnuri'ty. |