Blog Archives

Conception and Drainage Criteria

Posted by on 24/ 11/ 15

13.3.1 Road Alignment and Routing

For new roads, before drainage can be considered, the routing of the road must be fixed. Road routing is a complex procedure that involves very many factors including social, economic, engineering and environmental criteria as well as pub­lic acceptance. However, proper selection of the road corridor is one of the most important factors in the protection of water bodies. Technical measures aimed at mitigating a problem provide a poor substitute for efficient routing and alignment which could have avoided the occurrence of the problem altogether. Nevertheless, in those cases where conflicts between roads and water bodies cannot be avoided,

design of the road’s elements, together with technical measures, plays an important role...

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Design

Posted by on 24/ 11/ 15

Подпись:■ BY RANDALL WHITEHEAD

T

alk about energy-efficient lighting these days, and there are two technologies that are sure to dominate the discussion: fluorescents (usually compact fluorescents) and light-emitting diodes, or LEDs. As a lighting designer in California—where energy regulations are the strictest in the nation—I have a lot of these conversations. And I can tell you that rather than get­ting turned on by these newer, watt-saving technologies, most people are immediately turned off.

Why? Because most people have already had a lifetime of bad experiences with flick­ering, buzzing fluorescents and know little about LEDs, except that they’ve become ubiquitous as strings of the latest must-have holiday lights.

It’s not that these new light sources aren’t as good—or better—tha...

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Objectives

Posted by on 24/ 11/ 15

There are two aspects, which must be addressed in answering the question: “Why is road drainage so important?”. They are:

• A road’s infrastructure is an engineering work, aimed at the establishment of a platform on which vehicle circulation is possible under safe conditions, with proper traffic flow, utility, and economy, independent of the region’s climate con­ditions; and

• Water, along with heavy traffic, is one of the greatest causes of road deterioration. As previous chapters have shown, even relatively small increases in water con­tent can often result in significant reductions in the mechanical properties of the aggregate and soil layers in and under the road, thereby speeding up pavement failure.

The overall objective is, therefore, to keep the pavement and the subso...

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Hydraulic development and rise of the Qin kingdom (4th and 3rd centuries BC)

Posted by on 24/ 11/ 15

The kingdom of Qin, rising from the western valley of the Wei, begins to grow from 350 BC. Its leaders are tough, uninterested in moderate discourse and Confucian scholarship. In 417 BC they had occupied Lin-Tsin, one of the centers of the cult of the Yellow River at its confluence with the Luo (the other center of the cult was at Ye where Ximen Bao had put an end to the human sacrifices at about the same time). Since the Qin desired the river god’s protection for their family, each year they sacrificed a princess in “marriage.”[396] [397] The methods of the Qin were radical, one could even say bloodthirsty. But their leaders well understood the importance, to their own power, of economic development of the regions under their control...

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Single-objective versus multiobjective programming

Posted by on 23/ 11/ 15

The optimization model defined by Eqs. (8.1a-c) is for a single-objective problem. On the other hand, multiobjective programming deals with problems in­volving several noncommensurable and often conflicting objectives simultane­ously. Among the objective functions involved, no single one has an importance that is overwhelmingly dominant over all others. Under this circumstance, the ideological theme of optimality in the single-objective context is no longer appropriate.

Mathematically, a multiobjective programming problem can be expressed in terms of vector optimization as

Maximize f (x) = [ f 1(x), f 2(x),…, fM(x)] (8.2a)

subject to g(x) = 0 (8.2b)

in which f (x) is a vector of M objective functions, g(x) = 0 are vector of con­straints, and x is a vector of decision variables.

The solu...

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ATTACHING THE STOOL AND APRON

Posted by on 23/ 11/ 15

Lightly sand and prime the stool, including its underside and ends to prevent its absorbing moisture from condensation or driving rains. After the paint is thoroughly dry, apply water­proof glue to the underside of the stool, level it, and nail it to the rough sill using two or three 6d galvanized finish nails. Try not to lean on the only partially supported stool till it’s nailed to the top of the apron, which will steady the stool.

Next cut the apron, which is generally the same casing used for side and head casing, although here its thicker edge is butted to the underside of the stool. The apron should be as

Подпись: 1. After transferring the interior dimensions of the window frame to the stool stock, cut across the stock till the sawblade reaches the stool shoulder.

long as the head casing so that it lines up visually with the outside edges of the side casing...

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Construction

Posted by on 23/ 11/ 15

Swimming Pools and Hot Tubs

If you wish to include a swimming pool or hot tub inside your home, the two major health concerns to consider are water sterilization and humidity-related mold infestation. Пае standard disinfectants used to kill microbes and algae in swimming pools are chlorine or other halogenated compounds, which are easily absorbed through the swimmer s skin as well as inhaled into the lungs. Піеге are sev­eral alternatives to chlorination. Ozonation is a popular method used in Europe for steriliz­ing water. Other methods include electrolysis, ultraviolet light, and filtration through char­coal and pesticide-free diatomaceous earth. Pools using these alternate methods need to be frequently monitored for the presence of bacteria...

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Preparing the Girders

Posted by on 23/ 11/ 15

Once the floor was complete, I transposed the plans onto the deck with a black marker, at full scale. Now the position of every post could be seen clearly on the deck, and 1 could even show how the major south wall girders could abut with each other over the posts. See Fig. 5.22. I could check with the structure below to make sure that the line of thrust was transferred directly on compression to the post below, and not just missing them, as per Fig. 2.9 on page 24.

Before installing the posts, my family and I laid the girders out on the deck, supported on little blocks of wood. Then, the corresponding ends of the girders were cut at an angle so that they joined together fairly well...

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Fill holes and gaps

Posted by on 23/ 11/ 15

Once the trim has been installed, the next step is to set all the nails, then fill and sand the nail holes. Any nails that are above the surface of the wood must be driven below the surface with a nail set (see the photo at left on the facing page). If you plan to stain or polyure­thane the trim, fill the holes with matching wood putty. For paint prep, you can use painter’s putty or ordinary Spackle™ applied with a small putty knife or your finger.

Sometimes the miter joints (where the door and window trim meet) are not tight so you need to fill the gaps. There also may be slight gaps between the wall and sections of door and window casing or baseboard trim.

In addition, check for gaps between shelving and walls and around cabinets and other built-ins...

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Control of Pavement Water and Pollution Prevention

Posted by on 23/ 11/ 15

Jose Santinho Faisca[28], Jose Baena, Susanne Baltzer, Beata Gajewska, Antero Nousiainen, Ake Hermansson, SigurOur Erlingsson, Mihael Brencic and Andrew Dawson

Abstract This chapter sets out the requirements, possible problems concerning sur­face and subsurface water flow for pavements and offers some technical solutions to control these waters. It presents the general principles for the design and choice of a drainage system, the measures to adopt during construction and maintenance phases and considers the control of surface and subsurface water contamination, in order to minimize the possible detrimental effect to existing aquifers and habitats. This is achieved by a thorough review of available drainage measures, including many illustrations.

Keywords Road drainage ■ sub-soil drainage...

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