| Show DEPTH OF MACADAM tho tb thicker the th road 4 the tb greater ur tho are of the ina sustaining the th lewd lood many so to called macadam mac adani mals con ait mist of a few inches of broken stone laid on the surface of the ground without any provision for preventing the from spreading under ilia pressure of loada loads there should be made mane a trench trench of the width and depth intended for the roadbed I 1 or ligat traffic six inches of stone on an a good founds foundation tion will answer bat but for heavy bradlo this ie is not sum cicat the pressure ct of a load liaising over a compact road spreads cut through the body bencat Lj in conc con liLo clile form the opel being at the load on tin the surface tor face with a depth of bet but 0 iule ilia weight at the bottom will be ferend out ci 01 cr square inches if it it il ix 0 9 inches deep the th weight on the foundation will epic over 81 square In inches clies and if 13 12 incas deep it spreads over square inches depth of roadbed means Etre nath the tb area of the baso sustaining the weight of I 1 abe be load increases as the saul square to of the tho depth A road 12 inches deep is four times as stron aronas tr onas accle cloia ki x fuche deep |
