Blog Archives

Legal Responsibility

Posted by on 20/ 11/ 15

Estimates by the FHWA indicate that there are an average of 15 signs per mile on the nation’s 3.8 million miles of streets and roadways [6]. The resultant 57 million traffic signs represent a huge investment in materials, labor, equipment, and maintenance costs. While this is a significant investment, improvements using standard traffic control signing are reported in the “1988 Annual Report on Highway Safety Improvement Programs” as having the highest benefit-cost ratio of any highway safety improvement [7]. Properly designed, located, and maintained standard traffic signs and other carefully conceived devices can be an effective method of increasing traffic and operational efficiency and subsequently decreasing the tort liability exposure of roadway agencies.

The concerns about tor...

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. Corner trim, J-channel, and undersill trim

Posted by on 20/ 11/ 15

The corner trim pieces, which receive the ends of the vinyl siding panels, must be installed straight and plumb or they won’t look attrac­tive. Hold a short, cutoff piece of vinyl corner post against the sheathed corner of the house
and mark the edge of the flange on both sides of the corner at the top and bottom of the wall. Snap a chalkline between the marks. Set a corner post Z in. to И in. down from the sof­fit, and drive a l^-in.-long nail at the top of a slot on both sides of the corner. The corner post hangs from these nails, allowing the vinyl to move. Hold the posts directly on the chalk­lines and drive nails about every 12 in. in both flanges, down to the bottom of the wall. Keep each nail in the center of its slot. The corner posts should extend Zi in. to 1 in...

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VENTING TOILETS

Posted by on 20/ 11/ 15

Because they have the biggest drain and vent pipes of any fixture, toilets can be the trickiest to route vents for. When space beneath a toilet is not a problem, use a setup such as the one shown below, in "Venting a Toilet,” in which a 2-in. vent pipe rises vertically from a 3 by 2 combo, while the 3-in. drain continues on to the house main. The 3-in.-diameter toilet drain, allows the vent to be as far as 6 ft. from the fixture, as indicated in the table on p. 281.

When space is tight, say, on a second-floor bathroom with a finish ceilings below, the drain and vent pipes must descend less abruptly (see "Constricted Spaces,” below...

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Uniformity Considerations and Necessary Deviations

Posted by on 20/ 11/ 15

While the advantages of uniformity far outweigh the disadvantages, there are some undesirable effects when complete uniformity is maintained. One of the principal disad­vantages is that strict uniformity may result in the failure to adopt an improved device or procedure simply because it is not in common use. In addition, total uniformity would require the specification of a separate traffic control device for every conceivable road­way geometric and traffic operational condition. This would be a monumental task that undoubtedly would still not cover every situation, while simultaneously increasing the size of MUTCD with devices of limited application.

This difficulty is recognized in MUTCD, which indicates that warning signs other than those specified in the manual may be required under...

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STEP 2 INSTALL THE LEDGER

Posted by on 20/ 11/ 15

On a house built over a basement or crawl space, a deck or porch can be attached to the house frame. Deck building then becomes a lot like framing a floor-joist system inside a house (see

Chapter 3). Step one in this process is to attach a ledger to the house frame. Straight, level, and solidly secured to the house, the ledger acts like a rim joist for the porch. It extends the full length of the porch, supporting its inboard side.

There are several concerns when attaching a ledger, and all of them are important. First, the ledger must be at least 21/2 in. below the level of the interior floor. When l/Tin. deck boards are screwed on top of the ledger, the deck will be l in. lower than the interior floor, which is just about right...

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The Swedish Tjal2004

Posted by on 20/ 11/ 15

Tjal2004, developed by VTI, monitors temperature at every 50 mm down to a depth of 2 m. Temperatures are collected twice an hour and distributed via the Internet. The temperature sensors are calibrated to give highest possible accuracy close to 0°C where freezing starts. Trucks, having mobile Internet, pick up the current freezing situation from the installed Tjal2004 along the intended roads to travel. Road own­ers give truckers allowance to use roads as long as the upper part of the pavement is frozen down to a certain depth. This means that in spring, load restrictions are imposed and removed automatically and very frequently. During periods in spring with clear weather the situation might change daily...

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Venting Options

Posted by on 20/ 11/ 15

Until you expose the framing and actually run the pipe, it’s difficult to know exactly how things will fit together—especially vents. Because cor­rect venting is crucial, the section discusses sev­eral venting options to consider. But first, here are a few terms to keep straight: A stack is a verti­cal pipe. If the stack carries wastes, it’s a soil stack. If the stack admits air and never carries water, it’s a vent stack.

Most of the venting options described next are examples of dry venting, in which a vent stack never serves as a drain for another fixture. But there are hybrids; for example, if a vent stack occasionally drains fixtures above it, it is a wet vent. Wet vents must never carry soil wastes, and many local codes prohibit all wet venting...

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STEP 1 COMPLETE THE ESSENTIAL ROOF FRAMING

Posted by on 20/ 11/ 15

In many house designs, a section of the main roof extends over the porch. To complete the
installation of the roof trusses, roofing material, and exterior trim, the truss support beams over the porch must be cut and fastened to the wall framing. As shown in the illustration above, each beam rests in a pocket formed by a pair of jack studs framed in the house wall. The top of the beam is flush and level with the top of the wall plates.

In addition to nailing the beam to the wall framing, I strengthen the connection by nailing an 18-in. metal strap across the top of the beam and the double top plate of the wall. Beams made from rough 2x lumber can

Подпись: Larger decks may require more bolts to attach the ledger to the house frame. You have to think about the weight a deck might carry—a party with 50 people on a deck is a lot of weight.
STEP 1 COMPLETE THE ESSENTIAL ROOF FRAMING

later be covered with aluminum cladding, as described in Chapter 6.

If it’s not possible to install permanent posts at this stage, temp...

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Monitoring Frost Depth and Thawing, Finland and Sweden

Posted by on 20/ 11/ 15

8.3.5.1 Introduction

Spring-thaw load restrictions are often imposed to avoid severe pavement deteriora­tion during periods of reduced bearing capacity. Equipment that enables monitoring of the pavement strength situation is very important for a road’s traffic carrying capacity, as restrictions could be lifted as soon as the pavement regains its capacity. There are projects with this aim being run in both Sweden and Finland. In Finland the Percostation is used to monitor dielectric value, electrical conductivity and tem­perature with depth. The Swedish approach is to monitor temperature profile only and to distribute this via the Internet enabling direct access from trucks to frost depth readings that are updated twice an hour. Both approaches are now described.

8.3.5...

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Problems

Posted by on 20/ 11/ 15

As with other asphalt mixtures, problems frequently occur with SMA, too. They may develop at the stage of design, production, or application. Some of the troubles described here also appear in asphaltic concrete or other asphalt mixtures, but a dis­tinctive feature of SMA is that its shortcomings are revealed in a particularly clear, and sometimes painful, way.

This chapter presents an arranged collection of the most common defects observed in SMA. But before we begin, two issues need to be made clear:

• Each group of problems and their probable causes are provided here based on the author’s subjective assessment derived from his experience and con­sideration. Therefore it is obvious that a reader may have a different view on a given problem or that it may have another cause.

• Alway...

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