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Principles of Data Collection and Storage

Posted by on 18/ 11/ 15

7.2.1 Data Collection

It is a general rule that data must always be collected with a specific purpose in mind. This rule is as much true concerning contaminant levels in soils and groundwaters as it is in any other field. Therefore, before any sampling regime is contemplated and before any specimens are analysed, it is essential to decide the purpose for which samples and analyses might be required. Then a systematic sampling programme and network needs to be designed and planned with the purpose and constraints clearly in view. It is usually a non-routine task to identify the questions that need answering by the sampling and analysis programme. Perhaps these will be suggested because of standards set by an environmental regulator...

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Other patterns of Batching constituents in a Batch plant

Posted by on 18/ 11/ 15

The KGO-III (Viman et al., 2004) method has been experimentally applied in Sweden since 2002. It consists of changing the order of batching and mixing the constituents in a batch plant. The suggested KGO-III mixing order is as follows:

FIGuRE 9.5 One sequence of batching SMA constituents into a pugmill using a loose form of stabilizer. Notice that the times depend on the type of pugmill. (From Graf, K., Splittmastixasphalt – Anwendung und Bewahrung. Rettenmaier Seminar eSeMA’06. Zakopane [Poland], 2006. With permission.)

Подпись: Coarse and fine aggregates Added filler Stabilizer (loose fibers) Binder Wet mixing Discharging
Other patterns of Batching constituents in a Batch plant
Other patterns of Batching constituents in a Batch plant
Подпись: 50
Other patterns of Batching constituents in a Batch plant
Подпись: 10 s
Подпись: 10
Подпись: 60
Подпись: 20 Подпись: 70

FIGURE 9.6 Another sequence of batching SMA constituents into a pugmill using a loose form of stabilizer. Notice that the times depend on the type of pugmill. (From Schunemann, M., Faserqualitat...

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Overall summary of AFOSM reliability method

Posted by on 18/ 11/ 15

Convergence criteria for locating the design point. The previously described Hasofer-Lind and Ang-Tang iterative algorithms to determine the design point indicate that the iterations may end when x(r) and x(r+1> are sufficiently close. The key question then becomes what constitutes sufficiently close. In the ex­amples given previously in this section, the iterations were stopped when the
difference between the current and previous design point was less than 0.001. Whereas such a tight tolerance worked for the pipe-capacity examples in this book, it might not be appropriate for other cases, particularly for practical prob­lems. Thus alternative convergence criteria often have been used.

In some cases, the solution has been considered to have converged when the values of в(г) and віт+1) are...

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. EXTERIOR HINGED DOORS

Posted by on 18/ 11/ 15

. EXTERIOR HINGED DOORS. EXTERIOR HINGED DOORSПодпись:. EXTERIOR HINGED DOORSПодпись: SLIDING DooRПодпись: FIXED DOOR SCREEN DOORПодпись:. EXTERIOR HINGED DOORS

Sliding doors, whether they are wood, vinyl, fiber­glass, or aluminum, fasten to a building more like a window than like a hinged door. Because the weight of a sliding door remains within the plane of the wall, there is no lateral loading on the jamb of the door unit. Sliding doors are therefore supported on the sill and can be attached to the building like windows—through the casing or with a nailing fin. As with sliding windows most sliding-door manufacturers recommend not fastening the nailing fin at the head because header deflection can impede door operation.

Sliding doors are trimmed to the finish materials of the wall in the same way as swinging doors and win­dows (see 92-94).

HEADER SEE 68-70 SHEATHING

DOOR WRAP IF EXPOSED TO WEATHER SEE 89

NAILING Fin on

sheathing & under mo...

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Mixing SMA with a Loose Stabilizer

Posted by on 18/ 11/ 15

When incorporating a loose stabilizer, which is usually packed in shrink-wrapped bags, extra time is needed for dry mixing the stabilizer with aggregate. A bag of stabilizer is thrown into the pugmill when the filler is being batched, and then an extra period (about 3 seconds) of dry mixing the fibers with the aggregate follows. Because of this, they are released from the bag and evenly distributed in the mixture. The binder is batched onto the dispersed fibers and aggregates, and additional wet stage mixing time follows. Again, one should to remember that too long a dry mix­ing time could destroy loose fibers.

Figure 9.5 depicts one sequence of the batching of SMA constituents into the pugmill with the use of a loose stabilizer...

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Replacing a Shallow Foundation

Posted by on 18/ 11/ 15

If you decide to replace a shallow foundation, begin by checking local building codes for foun­dation specs appropriate for your area. Before

image433Подпись: Lally column capПодпись: Lally column (metal) —Подпись: (engineered lumber) (engineered lumber)Подпись: When it's necessary to construct a girder from several pieces of lumber, support each girder joint by placing a post or column beneath it. Many building codes also require metal connectors or plywood gussets at such joints to join posts to beams.

beginning foundation work, be sure to review this chapter’s earlier sections on shoring and jacking. Then survey the underside of the house and the area around the foundation for pipes, ducts, and other potential obstructions. If you can reposition jacks or move shoring slightly to avoid crushing or disconnecting drains, water pipes, and the like, do so.

Remember, jacking timbers and shoring are temporary supports. Complete the job and lower the house onto foundation elements as soon as possible...

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STEP 8 SEAL THE ROOF WITH FELT PAPER

Posted by on 18/ 11/ 15

Now that the house has been framed and sheathed, it’s time to seal it from the elements. As long as you are able to work safely on a roof, you can cover it with roofing felt and shingles. It’s best if all the plumbing and heating vents are through the roof before you install the felt.

If that isn’t possible, just make sure they’re installed before you begin shingling.

Roll out the felt paper

Felt paper, sometimes called tar paper or builder’s felt, is the first protective layer installed over roof sheathing. This material has evolved in a fashion similar to that of a candy bar. In the

old days, you could buy a good-size candy bar for a nickel. Today, you get a much smaller bar at a higher price...

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Cutting into a Concrete Floor

Posted by on 18/ 11/ 15

To enlarge an existing load-bearing pad or create one where none was, you may need to cut through a concrete floor. Depending on the condition and thickness of that floor, the job will range from nasty to horrible. Cutting concrete is noisy, dirty, and dangerous; and the tools are heavy and unpredictable. Wear safety glasses, gloves, hearing pro­tectors, and a respirator mask. Adequate ventilation and lighting are a must.

If the floor was poured before the 1950s, you’ll likely find that it is only 3 in. or 4 in. thick and is without steel reinforcing. The floor may also be badly cracked.

In this case, you can probably break through it with a pickax, but to minimize floor patching later, rent an electric concrete-cutting saw with a diamond blade to score around the opening...

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Contaminant Sampling and Analysis

Posted by on 18/ 11/ 15

Teresa Leitao*, Andrew Dawson*, Torleif Bakken, Mihael Brencic, Lennart Folkeson, Denis Francois, Petra Kunmska, Roman LiCbinsky and Martin Vojtesek

Abstract This chapter presents a general overview of procedures and methods for sampling and analysis of contaminants in water and soil in the road environment. The chapter concerns the water and seepage in road structures under the influence of traffic loading, and in the adjacent ground extending to the water table where contaminant seepage is of concern. The text gives an introduction to this subject and guides the reader to relevant literature with detailed information about practices of sampling and analysis...

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Inlet and Outlet Control

Posted by on 17/ 11/ 15

There are two types of flow in culverts: inlet control and outlet control. Accurate pre­diction of the condition of flow is difficult, and an assumption of the most conservative control may at times be warranted. Figures 5.12 and 5.13 depict several conditions of inlet and outlet control.

For inlet control, the discharge capacity is controlled at the upstream or inlet end. Factors that have an effect on the culvert performance under this condition are the headwater elevation, the inlet area of the barrel, and the inlet configuration. For outlet control, the discharge is controlled at the downstream end...

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