A large mountain road excavation project

The Rogers Pass route though the Canadian Rockies.

Let us look at a large mountain road excavation project, the Rogers Pass route through the Canadian Rockies. More than 90 miles long, it shortens by 100 miles the old Trans-Canada Highway Big Bend route along the Columbia River. At one time, this area was considered impractical as a highway route, but modern machinery and modern methods have changed this. The entire length involved 15 million cubic yards of soft excavation and 7 million cubic yards of rock excavation.

While the Rogers Pass route as a whole set many problems characteristic of mountain work, the major problems lay in the 27-mile section through the Glacier National Park. Here, in a narrow valley surrounded by towering mountains, is the heart of the avalanche country. In rain, silty material becomes a soft unworkable mud, bogging everything down. Muskeg swamps near the summit of the pass gave the engineers many a headache. The country is under ice and snow in the winter, so that work could go on only in the short summer. In the spring, when the thaw set in, the melting ice brought down dangerous avalanches. Heavy runoff of melting snow and water from the mountain tops poured down the steep slopes of the sidehill cuts and turned them into a quagmire that hindered both men and machines.

The route cuts into the steep mountain sides far above the valley below. Men clearing the ground ahead, and drilling the rock for blasting, had to work with ropes around their waists; the ropes were tied to anchors above. Bulldozers cut a narrow "bench" or shelf in the mountainside to serve as a footing for the main excavation machines, which followed and widened it out to the full width. These bulldozers sometimes worked in pairs, one high above and well anchored down, holding the working bulldozer below by a strong wire rope. The men call this arrangement the "Yo-Yo". They never seem to mind the dangerous nature of their work; they never seem to consider that the steel rope might break. Perhaps they know their engineers have worked it all out carefully and watch everything like hawks.

IX. What geological problems did this project have for construction engineers?

X. Find the definitions for certain construction machines:

1) bulldozer 4) excavator 7) pile driver

2) dragline 5) grader 8) roller

3) dumper 6) paver 9) scraper

a) An earth - moving vehicle with the barrow part in front of the driver.

b) An earth - moving machine designed mostly for pushing heavy loads of earth. If is mounted on caterpillar tracks and has a heavy blade.

c) Any powered digging machine.

d) A rood- making machine that mixes and pours the surfacing material (usu. concrete) along the roadway.

e) A road- making machine that digs by scooping toward, itself with a bucked handing from the end of a long jib.

f) A vehicle used to prepare the roadbed. It scrapes the surface to level it.

g) An earth - moving machine consisting of a large bucked that is dragged along the ground on its side, scrapping up the earth.

h) A road- making vehicle, used for compacting the roadbed and the road surface.

i) A machine that lifts the piling into position and incorporates the pile hammer that drives it into the ground.

XI. Look at the pictures of road-making machines and think of the possible functions of each of them:

1. 2.

3. 4. 5.

Road-making machines: (1) tractor with scraper for tearing up and hauling away soil; (2) dumper; (3) compactor; (4) excavating tractor; (5) grader.