Concrete and Cement Jobs

About Concrete and Cement Jobs

Cement masons, concrete finishers, and terrazzo employees all work with concrete, one of the most typical and sturdy materials employed in construction.

They also may color concrete surfaces, reveal total ( little stones ) in walls and paths, or fabricate concrete beams, columns, and panels. In cooking up a site to set concrete, cement masons first set the forms for holding the concrete and correctly align them.

They then direct the casting of the concrete and control workers who use spades or special tools to spread it. Masons then guide a straightedge backwards and forwards across the apex of the forms to "screed," or level, the freshly placed concrete.

Concrete finishers employ a special tool called a "groover" to make joints or grooves at particular intervals that help control cracking.

Next, they smooth the surface using either a powered or hand spade, a little, smooth, rectangular metal tool. Often , cement masons perform all the steps of laying concrete, including the finishing. As the final step, they retrowel the concrete surface forwards and backwards with powered or hand spades to make a smooth finish.

For a coarse, nonskid finish, masons brush the surface with a brush or stiff-bristled brush. For a pebble finish, they embed tiny gravel chips into the surface. They then wash any extra cement from the exposed chips with a mild acid solution. For color, they use colored premixed concrete. Finally, they coat the exposed area with a rich Portland cement mix, using either a special tool or a coarse fabric to rub the concrete to a uniform finish.

Across the complete process, cement masons must monitor the way the wind, heat, or cold is affecting the curing of the concrete. Segmental pavers lay out, cut, and install paversflat pieces of masonry made of compressed concrete or brick.

Customarily the work includes building edges to stop horizontal movement of the pavers.

Sand is then added to fill the joints between the pavers.Terrazzo workers create attractive walkways, floors, patios, and panels by exposing marble chips and other fine aggregates on the surface of finished concrete. Much of the preliminary work of terrazzo workers is similar to that of cement masons. There are six different types of terrazzo, but the focus of this description is on the most common standard terrazzo: Marble-chip terrazzo, which requires three layers of materials.

First, cement masons or terrazzo workers build a solid, level concrete foundation that is 3 to 4 inches deep. Second, after the forms are removed from the foundation, workers add a 1-inch layer of sandy concrete. Terrazzo workers partially embed, or attach with adhesive, metal divider strips in the concrete wherever there is to be a joint or change of color in the terrazzo.

For the third and final layer, terrazzo workers blend and place into each of the panels a fine marble chip mixture that may be color-pigmented. While the mixture is still wet, workers add additional marble chips of various colors into each panel and roll a lightweight roller over the entire surface.

When the terrazzo is thoroughly set, helpers grind it with a terrazzo grinder, which is somewhat like a floor polisher, only much heavier. Any depressions left by the grinding are filled with a matching grout material and hand-troweled for a smooth, uniform surface. Terrazzo workers then clean, polish, and seal the dry surface for a lustrous finish.

Work environment. Concrete, segmental paving, or terrazzo work is fast-paced and strenuous, and requires continuous physical effort. Because most finishing is done at floor level, workers must bend and kneel often. Many jobs are outdoors, and work is generally halted during inclement weather.

The work, either indoors or outdoors, may be in areas that are muddy, dusty, or dirty. To avoid chemical burns from uncured concrete and sore knees from frequent kneeling, many workers wear kneepads. Workers usually also wear water-repellent boots while working in wet concrete.

Most workers work 40 hours a week, although the number of hours can be increased or decreased by outside factors. Earnings for workers in these trades can be reduced on occasion because poor weather and slowdowns in construction activity limit the time they can work.