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Drainage Masks

Posted by on 25/ 11/ 15

Drainage masks provide control of emerging water (e. g. a spring line) on a slope’s face with a geotextile covered by hand-placed rock (Fig. 13.21). The material used for a drainage mask should be angular and should comprise 100-500 mm sized stone. The rock provides improved slope stability both by allowing the reduction of pore water pressures without erosion and by adding mass to the slope.

Fig. 13.20 ‘ ‘Christmas tree” drain

Fig. 13.21 Drainage masks

13.4.4.2 Drainage Spurs

Drainage spurs have the double function of draining and reinforcing the excavated slopes. Spurs are constructed as stone-filled trenches excavated perpendicular to the slope face (Fig. 13.22) to provide both drainage and buttress support...

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MAINTENANCE CONSIDERATIONS

Posted by on 25/ 11/ 15

It is wise to keep a stock of compatible replacement materials on hand to repair damage from impact or vandalism. Consideration should be given to keeping replacement materials where they can weather to match installed barriers, such as for pressure-treated timber components. Also, if color is added to concrete panels during manufacture, it is desirable to make future replacement panels in the same operation.

The control of graffiti remains a problem in some urban areas. There are some anti­graffiti surface treatments available, but they are generally costly. Power washing and repainting are current options.

Plantings should be tolerant of roadside environments and require little or no maintenance. Access must be provided to both sides of the barrier for mowing, general maintenance, etc...

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SAFETY CONSIDERATIONS

Posted by on 25/ 11/ 15

Care must be taken not to install a noise barrier in such a way that it will be a safety haz­ard. The general considerations presented in Chap. 6, Safety Systems, apply here. Noise barrier design should incorporate all of the safety design techniques used in the basic roadway design. Examples of features that should be considered include trans­verse location to provide required clear zone, slopes of berms, sight distances, wall ends, plantings, and transitions.

Ideally, noise barriers should be located beyond the clear zone. If not, a traffic barrier may be warranted. It is usually best to design the traffic barrier as part of the noise barrier...

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Net Current in Utilities

Posted by on 25/ 11/ 15

After purchasing a gaussmeter, an electrician was surprised to discover an elevated magnetic field throughout his entire driveway and a portion of his home. Upon learning that the field did not de­cline when he shut off the power to his home at the main breaker, he concluded that the source of the field was from net current in the gas line. A gas company technician visited the siteand confirmed that the gas line was carrying electricity. There was no cause for concern, he said, because the amount of electricity was small.

The electrician was not comforted by such reassurances. As a specialist in complex wiring

techniques for boats and marinas, he was familiar with the problems of electrolysis and galvanic ac­tion resulting from electricity straying from its in­tended path...

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Task and Accent Lighting Require Focused Light

Posted by on 25/ 11/ 15

LEDs produce a focused beam of light. Al­though their relatively small output means they can’t throw light as far as some incan – descents, there are plenty of circumstances where they work well as task lights. And they’re ideal for accent lights because they don’t produce UV-light that damages paint­ings and fabrics. Because LEDs are small and easily produced as pucks or strip lighting, they are ideal for undercabinet illumination or as accent lights hidden in coves or inside cabinets, where small size and low heat out­put are important.

Glare can be a concern with bright LED fixtures, especially recessed lights. San Francisco Bay Area lighting designer Eric

Подпись:Task and Accent Lighting Require Focused LightKind of canlike...

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HOW DOES A SEPTIC SYSTEM WORK?

Posted by on 25/ 11/ 15

How does a septic system work? A standard septic system works on a very simple principle. Sewage from a home enters the septic tank through the sewer. Where the sewer is connected to the septic tank, there is a baffle on the inside of the tank. This baffle is usually a sanitary tee. The sewer enters the center of the tee and drops down through the bottom of it. The top hub of the tee is left open.

The bottom of the tee is normally fitted with a short piece of pipe. The pipe drops out of the tee and extends into the tank liquids. This pipe should never extend lower than the outlet pipe at the other end of the septic tank. The inlet drop is usually no more than twelve inches long.

The outlet pipe for the tank also has a baffle, normally an elbow fitting...

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Refinishing Wood Floors

Posted by on 25/ 11/ 15

Wood floor refinishing can be as simple as lightly sanding an existing finish and applying another coat of the same finish or as extensive as strip­ping the floor finish completely and sanding it several times before applying a new finish. If the floor is just grimy and dull from too many coats of wax, it may just need a thorough washing.

If washing doesn’t do the trick, try to determine what the existing finish is before you rent a sander.

THREE TESTS TO DETERMINE A FLOOR FINISH

Wood floors installed in the 1960s or earlier were usually finished with some combination of wax, shellac, and varnish. After that, they were most likely finished with a penetrating oil, or oil – or water-based polyurethane. (For more on finishes,
see p. 494...

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Match the Light to the Job

Posted by on 25/ 11/ 15

Both CFLs and LEDs are available with screw-in bases as replacement bulbs for ex­isting fixtures, but if you are building a new home or remodeling, you might consider fixtures dedicated to one technology or the other. Dedicated fixtures can lengthen the lifespan of the bulb and maximize its strengths. Both CFLs and LEDs play a role in providing ambient, accent, task, and deco­rative lighting, the four layers that create a well-lit room. But CFLs and LEDs aren’t necessarily interchangeable. That’s largely because CFLs are a multidirectional light source and LEDs are a point source.

Because they are multidirectional and produce large amounts of diffuse light, CFLs work well for ambient, task, and decorative lighting (photos pp. 160-161). They can be used nearly everywhere that incandescent...

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The technologies of the medieval revival

Posted by on 25/ 11/ 15

The conquest of the waterways: inland water transport and mills

The great technological phenomenon of the Middle Ages is the development of mills, perhaps a natural companion of the revival of interest in watercourses. Since the road network was in bad shape and the countryside was not safe, the development of com­merce in the 10th century first relies on the watercourses. Demographic expansion and the nearly exclusive use of cereals to feed the population drive major development of the flour trade. In this period the consumption of bread made from flour develops while consumption of porridge decreases. It was quite natural to build mills along watercours­es that were already indispensable for water supply and transport, a heritage from the Roman era...

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