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Show HO W TO A VOID MISTAKES IN "ROAD-MAKING : PROPER METHODS OF MAKING EARTH, CLAY, SAND, AND GRAVEL ROADS AS RECOMMENDED ; BY GOVERNMENT EXPERTS Tho cost of hauling over country roads is largely determined by tho.slzc of the load that can bo hauled, tho number of trips that can bo made- Jn a day and the wear nnd tear on teams and equipment. Steep grades as well as ruts nnd mud-holes servo to decrease de-crease both tho speed and tho load. On the prlnclplo that "a chain Is no stronger than its weakest link," the maximum load that a team can draw Is tho load that it can draw up tho steepest hill or through the deepest deep-est mud-holo on that road. Wherever possible, roads should he located on straight lines. In a hilly or mountainous country, however, stralghtness often causes hoavy grades. SlraightnoM and grade must, therefore, there-fore, be handled together. Tho best location Is one which Is straight In general directions, is free from stoop grades. Is over solid ground, and serves tho largest possible number of people. In studying tho relations of grado to distance, tho following prlnclplo should be borno in mind: To lift a ton ono foot high requires 2,000 footpounds foot-pounds of energy; on a road, the surface sur-face of which offers 100 pounds of tractive resistance per ton, tho samo energy would roll tho ton a horizontal distance of 20 feet. To save ono foot of grade tho road may therefore bo lengthened 20 foet. The elimination of ono or two steep hills on a line of road will frequently enable horses to draw thrco or four times as much as they could draw on the old road. It takes approximately four times as much power to draw loads tip 10-por-ccnt grades as on a level, but on a 4 per-cent or 3 per cent grado a horso can usually draw (for a short time) as much as ho can draw on a lovcl. A I per cent or 6 per cent grade Is 3&mM 1 Two common mistakes in rontl-m: poorly located. thcroforo considered the maximum on roads subjected to heavy hauling. Steep grades may often bo avoided by locating the road around Instead of over the hill, without materially increasing in-creasing tho distance. Tho earth road should ha o at least six houra of sunshlno each day. Such brush and trees as Impcdo the drying nctlon of the sun and wind should be romoved. "With gravel and stono roads, this is not so necessary, as a certain amount of inoisturo le needed on such roads, especially during the summer. Relocating roads Is not nn engineering engineer-ing problem alone. One must also consider con-sider tho effect of tho road on those who now live upon It. Many dislike to have the road placed back of their houses, or out of sight of It. It requires re-quires tact and good judgment to sc-curo sc-curo a suitable location without arousing arous-ing harsh antagonism. Tho earth road can best bo crowned nnd ditched with a revcrsiblo road-graior. road-graior. Picks, shovels, scoops and plows should not ho used for this purpose. pur-pose. Ono road-machine, with suitable suit-able power and operator, will do tho work of many men with picks and shovels, and do it bettor. Tho grader should bo usod when tho soil Is damp, so as to make the soil bako and pack when I dries out If it Is worked dry, it takes more power to draw the machine, and, bo-slde. bo-slde. dry earth and dust retain moisture mois-ture and quickly rut after rainp Clods, sods, weeds or vegctablo matter should not bo left In the middle of the road. In order to dispose of storm water quickly before It hns time to pene-trato pene-trato deeply into the surface, the road should bo properly crowned. For nn earth road which Is 2-i feet wldo, tho center should bo not loss than 6 Inches nor moro than twolvo Inches higher than the other edgo of tho shouldero. The total fall of grndo from center to sldo ditch shoiild be about an 1 1 j cjr , tsZF st ,J9 c i7J I iking. The poorly drained nnd the i 'inch to tho foot. Ordinarily, tho only ditches needed aro those made with the road grader, which arc wldo and shallow. Deep ditches should be provided pro-vided If the road Is about level, but such ditches wash rapidly on steep slopes and arc dangerous beside. Wood or terra-cotta lllo do not make satisfactory culverts; tho first will soon rot and tho latter is liable to break. Stono or concrete culvorts aro the best and cheapest in the long run Tho main thing to bear In mind in building culverts Is that they should have sufficient capacity to quickly dispose dis-pose of tho maximum How of storm water, and that they aro given sufficient suf-ficient slope or fall to keep themselves clean. Because of Its simplicity, Its efficiency effic-iency and cheapness, tho splltlog drag is an excellent dovlco for maintaining earth nnd gravel roads. i A country road In March In ono of I the richest States In tho Union. The best results havo been, obtained by dragging once each way after each heavy rain. In some cases, however, ono dragging every three or four weeks had bcon found sufficient to keep a road in good condition. Tho drag does its best work when tho soil is "moist but not sticky." The sand-clay road is made by mixing mix-ing sand nnd clay together. Coarse, sharp sand and sticky clays aro preferred. pre-ferred. A proper mixture will produce pro-duce a hard surface, which In mild climates and for light traffic will not become looso when dry nor sticky when wet. Ordinarily from 10 to 13 per cent j of clay and from S5 to 90 per cent I of sand constitute the proper mixture. If tho road to bo treated Is sandy, j tho surfaco Is first levolcd ort and crowned with tho road-grader. The I clay Is then dumped on the surface and spread to a depth of from G to S Inches at tho center, and gradually decreasing In depth toward the sides. A layer of clean sand is then added, which is thoroughly mixed with the clay, cither by traffic or preferably by means of plows and disk or tooth harrows. har-rows. Tho sand-clay road, after completion, comple-tion, should bo carefully maintained until the surfaco bocomes firm and smooth. The construction of this type of road Is by no means a quick operation. oper-ation. Thcro arc so many kinds of gravel that it is almost Impossiblo to lay down principles of construction which ulll hold good In all cases. The following are the principal causes of failure In gravel roads: First, poor material; round water-worn water-worn gravel; too little binder or too much sand, earth or clay. Second, unstable foundations: placing plac-ing gravel on surfaces filled with ruts and holes. I Tho middle west hns too ninny of these poorly built gravel ronds. Third, poor drainage; too fiat, or too high in tho middle, side ditches loo deep or not deep enough, culvorts which nro too small, or which arc laid so flat that they aro soon filled with silt or trash. Fourth, spreading gravel in dry weather, dumping it in piles and leaving leav-ing it for the traffic to spread. Fifth, making the road too narrow to accommodate tho traffic, or so nar-raw nar-raw that wagons will track and soon cut the surfaco Into ruts. Sixth, failure fail-ure to keep ruts and holes filled with gravel. With good binding or cementing gravel, satisfactory roads may be made by surfacing tho prepared subgrade with one or two layers of this material. mat-erial. The earth foundation is first shaped with a road-grader, and If possible, rolled with an eight or ten-ton ten-ton roller. .. Tho earth foundation should be crowned but 3llghtly. Tho 'material Is spread In one, two or thrco layers to a total depth of from S to 12 Inches in tho center, and from A to C Inches at tho sides, gradually dlminishing in depth to a feathcredge toward tho sldo ditches. Tho gravel road ought to havo a llttlo attention throughout the year instead of a great deal of attention at one time. Mud-holes should never be filled with large rocks or boulders; sods or trash. After tho mud has been removed, the holes should be filled with the samo kind of gravel with which the road i3 surfaced. Whon tho gravel road is worked with a road machine tho sods and weeds arc often left In windrows In tho middle. These should be raked up and thrown Into tho adjacent field or otherwise disposed of. as they retain re-tain molsturo and causo lumps and holes if left on the road. - - Well drnined enrth road in Yam 1II1I County, Orcson. |