Blog Archives

The appearance of the chamber lock

Posted by on 24/ 11/ 15

The chamber lock, with two gates, is invented in the Song Dynasty at the end of the 10th century. In 983, a civil servant named Chiao Wei-Yo is in charge of transport in the Huai region. At this time barges were transferred from the canal to the Huai, at the northern extremity of the Shangyang traverse, by dragging them on an inclined ramp. This oper­ation often damaged the heavily-loaded barges and their cargo. To remedy this difficul­ty, Chiao Wei-Yo conceived the concept of the chamber lock, the very first such device in the history of man:

“Chiao Wei-Ho therefore ordered the construction of two gates at the third dam along the west river. The distance between these two gates was a little more than 50 paces (75 m) and the entire space was covered with a large roof. […...

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Painting the Exterior

Posted by on 24/ 11/ 15

Exterior paint jobs can last 10 years or more if you’re fastidious about prep work and attentive to water-related building details. Key factors include proper flashing of windows, doors, and roof junctures; maintaining gutter systems; caulking gaps in exterior siding; and adequately venting excess moisture from interior spaces.

WHY PAINT FAILS

Before you sand or scrape anything, figure out why the paint is failing. . . and where.

Blistering is usually caused by painting over damp wood or an earlier coat of paint that isn’t dry. Blisters often contain water vapor, although "temperature blisters” are largely hot air, caused by painting a surface that was too hot. Scrape and sand blisters, allow the wood siding to dry thoroughly; then spot prime.

Peeling off in sheets, is blistering on a gr...

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Green—and Unseen

Posted by on 24/ 11/ 15

When I show my clients a typical CFL— the type shaped like swirly soft ice cream— they immediately hate it. It doesn’t matter if the light it produces has a beautiful color, if it operates quietly, or if it’s dimmable. They just have a visceral, negative reac­tion because they can see that the source
of light is fluorescent. I’ve learned to apply a technique I call stealth lighting. Stealth lighting simply means hiding the bulb be­hind a diffusion material such as a shade, an architectural detail, or a lens. If they can’t see that it’s a fluorescent source, most people assume the light is incandescent and find it perfectly acceptable.

When selecting a decorative fixture—for example, a pendant light—find a bowl­shaped one that hides the bulbs; in the case of a drum-shaped fixture, look...

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Hydrograph Attenuation

Posted by on 24/ 11/ 15

Normally, rain falling on impermeable surfaces, such as a road surface, quickly enters the drainage system, arriving at the outfall to river or stream very soon after falling from the sky. It is estimated (Interpave, 2005) that in a fully forested, lowland catchment only 5% of rainfall will flow across the ground surface, the remainder will be delayed by the vegetation to such an extent that it will soak into the ground. For agricultural land with less vegetation 30% may flow across the surface. However for an urban environment with piped stormwater drainage systems 95% is carried to the surface water bodies...

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Kjellbase

Posted by on 24/ 11/ 15

Colored asphalt surfacing is an aesthetically pleasing option. Colored wearing courses can also be executed with fine-graded SMAs (Blazejowski and Styk, 2000) using special synthetic (colorless) binders. Besides their aesthetic appeal, colored surfacing can also be used to mark pedestrian crossings or other safety-related features.

When making colored SMA, it is important to remember to carefully clean the asphalt plant, mixer, and silos, removing “black” mix remains. Loose fibers, specifi­cally those containing no binder additives and bright aggregates, should be applied.

Kjellbase

The strong mineral skeleton applied in SMA has attracted some followers. After all, nothing stands in the way of using similar mixes in intermediate courses or base layers. Kjellbase makes such a mix...

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STEP 3 INSTALL THE WINDOW AND DOOR CASINGS

Posted by on 24/ 11/ 15

If you’ve installed prehung doors with the cas­ing (trim) attached, then some of your trimwork has already been done. If not, then the time to trim the windows and doors is now. Remember: Accuracy is critical for good finish work. All joints between pieces of wood should be tight, with no space showing.

Doing a good job depends on having the right tools, measuring carefully, and using a few finish carpentry tricks. Make sure you have a
good chopsaw that is fitted with a finish­cutting blade. A pneumatic nailer is a tremen­dous time-saver when installing trim, and it ensures that installed pieces won’t be marred by hammer blows (see the photo above). However, you can still do the job the old-fashioned way if you have to—with a hammer, finish nails, and a nail set...

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The Grand Canal

Posted by on 24/ 11/ 15

The Grand Canal of the Sui, the Tang, and the Song (6th to 11th century)

In 581 AD, Yang Jian founded the Sui Dynasty at Chang’an. He reunifies China in 589, and in 604 the country sees its new master enthroned as emperor. An imperial necessi­ty appears immediately: to establish a safe communication route between the north of China where the reconstructed capital Chang’an is located, and the Yangtze basin to the south. This need reflects a fundamental change in the relations between north and south

The Grand Canal

Figure 8.12 The Grand Canal of the Sui, the Tang and the Song.

1. Shanyang traverse (renovated in 587)

2. Tongji canal (605)

3. Yongji canal (608)

4. Jiangnan canal (610)

5. Northern detour of Hongze lake (about 735)

since the Han period...

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The Pavement as a Water Reservoir

Posted by on 24/ 11/ 15

A book on Water in Road Structures would not be complete without a brief descrip­tion on the use of the pavement as a water store. Pervious pavements (see Chapter 5, Section 5.7) can be taken one step further and not only used to convey water away from the surface, but can also be used to temporarily store the water in the pavement. There are two principal reasons for doing this

• hydrograph attenuation and

• water quality improvement.

Here, the use of pervious pavements may only be briefly discussed, but inter­ested readers may find out much more in the book devoted to the topic by Ferguson (2005). Typically they comprise highly permeable surfaces (e. g...

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Mechanical

Posted by on 24/ 11/ 15

Water Supply and Waste

Polyvinyl chloride (PVC) is the standard for residential supply and waste piping. PVC plas­tic piping has been shown to outgas diethyl phthalate, trimethylhexane, aliphatic hydro­carbons, and other harmful gases. It should not be used for water supply piping in a healthy home. Because of the pollution resulting from both the manufacture and the disposal of PVC piping, we recommend seeking alternatives for waste lines as well.

Water Supply Pipe

Although we can choose the type of supply pipe we want in a new home, we have no con­trol over how water is delivered to our prop­ertyline. Well water is often delivered through PVC piping. Municipal water supply can be piped through a variety of unsavory piping, including PVC and asbestos cement...

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Optimal Risk-Based Design of Hydrosystem Infrastructures

Posted by on 24/ 11/ 15

Reliability analysis methods can be applied to design hydrosystem infrastruc­tures with or without considering risk costs. Risk costs are those cost items incurred owing to the unexpected failure of structures, and they can be broadly classified into tangible and intangible costs. Tangible costs are those measurable in terms of monetary unit, which include damage to property and structures, loss of business, cost of repair, etc. On the other hand, intangible costs are not measurable by monetary unit, such as psychological trauma, loss of lives, social unrest, damage to the environment, and others. Without considering risk costs, reliability has been explicitly accounted for in the design of storm sewer sys­tems (Yen and Ang, 1971; Yen et al., 1976; Yen and Jun, 1984), culverts (Yen et al...

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