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Techniques CROSS-SIGHTING A JAMB

Posted by on 24/ 11/ 15

  Techniques CROSS-SIGHTING A JAMB

Techniques CROSS-SIGHTING A JAMBTechniques CROSS-SIGHTING A JAMB

Подпись: LEAVE ENOUGH OPER-ATING CLEARANCE. Leave a Ye-in. margin between the door and the jamb so the door can open and Close freely. [Photo by Andy Engel, courtesy Fine Homebuilding magazine, ® The Taunton Press, Inc.] Подпись: KEEP THE JAMBS STRAIGHT. A heavy door can bow a jamb inward at the top hinge. Straighten the jamb by lifting up the door on the lock side and then nailing the jamb securely in place. [Photo by Andy Engel, courtesy Fine Homebuilding magazine, ® The Taunton Press, Inc.]

Techniques CROSS-SIGHTING A JAMB

thickness of a nickel, all the way across the top (see the top photo above). If the margin at the top is too tight (less than % in.) or too wide (more than % in.), it can be corrected by rais­ing a jamb side. The hinge side can be raised, even with a nail at the top, with a flat bar

under the jamb. Once the margin is correct, nail again near the bottom hinge. Remember to shim under every jamb that doesn’t rest directly on the subfloor.

When setting heavy doors, the weight on the top hinge can bow the jamb outward. If that happens, place a bar under the door and raise the strike (lock) side of the closed door until the hinge jamb is straight or even bowed back slightly. Then drive a nail through the jamb on the hinge side, both above and below the top hinge.

You don...

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Durability Considerations for MSE Walls with Polymeric Reinforcement

Posted by on 24/ 11/ 15

The durability of polymeric reinforcements is influenced by time, temperature, mechanical damage, stress levels, microbiological attack, and changes in the molecular structure due to radiation or chemical exposure. The effects of aging and of chemical and biological exposure are highly dependent on material composition, including resin type, grade, and additives; manufacturing process; and final product physical structure.

Polymeric reinforcement, although not susceptible to corrosion, may degrade as a result of physicochemical activity in the soil, such as hydrolysis, oxidation, and environ­mental stress cracking. In addition, it is susceptible to construction damage, and some forms may be adversely affected by prolonged exposure to ultraviolet light...

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West Bridge on the Great Belt Link, Denmark

Posted by on 24/ 11/ 15
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Another example of an SMA bridge application in Europe is found on one of the longest bridges in Europe—the Great Belt Link connecting Denmark with Sweden.

FIGuRE 13.1 Grading of the SMA aggregate mix, Roosteren design. (Data from von Brochove, G. G., Voskuilen, J., and Visser, A. F.H. M., Proceedings of the 4th Eurasphalt & Eurobitume Conference, Copenhagen, paper 402-102, 2008.)

It is a 6600-m long, prestressed concrete structure with an asphalt pavement consist­ing of the following courses (Wegan, 2000):

• 15 mm open graded asphalt concrete (drainage layer)

• 40 mm thick asphalt concrete (protective course)

• 40 mm thick SMA (wearing course)

The expected lifespan of the SMA layer on this bridge is 25 years.

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Examples of SMA Pavements on Bridges

Posted by on 24/ 11/ 15

What follows are descriptions of a few applications of SMA-type asphalt mixes for pavements on steel bridge decks. It has been noted before that this type of bridge construction poses the greatest challenge for the asphalt pavement.

13.2.1.1 Bridge in Roosteren, the Netherlands

In 2005, in Roosteren, the Netherlands, an experimental SMA pavement was made with mastic containing a binder that was highly modified with elastomer (Pen@25°C = 50/70, SP > 90°C) instead of typical mastic asphalt (von Brochove et al., 2008). Demanding requirements, as follows, were required of the SMA mix to compare it with mastic asphalt:

• Resistance to permanent deformation measured by the triaxial compression method after EN 12697-25

• Cracking resistance by the method based on the semicircular bending test...

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Tools and Equipment

Posted by on 24/ 11/ 15

Ladders and scaffolding are essential for many painting jobs. For more on them, see Chapter 3.

MASKS AND CARTRIDGES

Disposable paper masks will keep out sanding dust, but you need a filtered mask when spraying paints or applying chemical strippers. For any task involving leaded paint, wear a full-face respi­rator mask with replaceable HEPA (purple) car­tridges. For most paint applications, a half-face mask with replaceable organic vapor cartridges will be adequate. Masks vary, so pick one that fits your face snugly. To test the fit, when you cover cartridge openings and inhale, no air should enter the mask.

Cartridge life varies according to the chemical you’re using, the type of filter specified for that chemical, ventilation in your workspace, and the care you take to keep cartridges “...

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Window Testing

Posted by on 24/ 11/ 15

Water infiltration caused by faulty windows or installation procedure is a common source of building failure leading to mold infestation and water damage. Because water infiltrating through window assemblies will often leak directly into the wall cavity, a problem can go undetected for a long time and once it is dis­covered the damage is often extensive.

Such problems can be avoided if the proper testing protocol is carried out at the time of in­stallation. Some windows are designed with drainage channels and weep holes that allow water to drain to the outside of the building and not into the wall. One way to test the ef­fectiveness of a windows drainage capacity is to temporarily block the weep holes with putty and then fill the drainage channel with water...

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Durability Considerations for MSE Walls with Metal Reinforcement

Posted by on 24/ 11/ 15

Where metallic reinforcement is used, the life of the structure will depend on the corro­sion resistance of the reinforcement. Practically all the metallic reinforcements used in construction of embankments and walls, whether they are strips, bar mats, or wire mesh, are made of galvanized steel. Epoxy coating can be used for additional corrosion protection, but it is susceptible to construction damage, which can significantly reduce its effectiveness. PVC coatings on wire mesh also provide corrosion protection, provided again that the coating is not significantly damaged during construction. When PVC or epoxy coatings are used, the maximum particle size of the backfill should be restricted to /4 in (19 mm) or less to reduce the potential for construction damage.

For the purpose of determi...

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The Han Empire: continuing hydraulic development. Awakening of the Yellow River

Posted by on 24/ 11/ 15

The First Emperor left the legacy of an energetic, but bloody, monarchy to Chinese his­torians. And this is no doubt why the Qin Dynasty could not survive it. It is replaced by the long Han Dynasty, dominating China for more than four centuries from 206 BC to 220 AD. The Empire continues to encompass the basins of the two great rivers, and even extends to the south as far as Canton and to the west into the corridor of the Silk Road, nearly to Bactria. But the demographic and economic center of gravity remains in the north. The census of the year 2 AD showed 85% of China’s 57 million people to be in the north. The most populated zones[408] are the Wei valley, ancient nursery of the Qin, and the vast alluvial plain of the lower course of the Yellow River down to the sea, between the Jiang...

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Moisture Meters

Posted by on 24/ 11/ 15

There are two general types of moisture me­ters. The first uses sharp pin probes that are pushed into the material to be tested. The pin probe meter detects moisture by electri­cal conductivity, since wet materials conduct greater amounts of electricity than dry materi­als. This meter leaves pinholes in the materials being tested. The second type of meter sends an electronic signal into the material. The de­gree of moisture determines how the meter will register the returning signal.

Both types of moisture meters are bat­tery operated and can be used repeatedly. The meters range in cost from about $200 to over $1,000 and can require some technical expe­rience. For example, damp wood is measured with a different setting and scale than damp concrete or brick...

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Porous Asphalt

Posted by on 24/ 11/ 15

Although they may not be considered as part of the drainage system, a pervious type of asphalt treated surface layer, known as porous asphalt, has become common in Europe in recent years. The main advantages attributed to porous asphalt layers are noise reduction, improvement of skid resistance in wet weather, and enhancement of runoff water quality. Asphalt treated drainage layers of this type are discussed further in Chapter 5, Section 5.7.

13.3.4.2 When Drainage is Unnecessary

Some authors suggest that subsurface drainage may not be necessary if:

• annual rainfall is not significant;

• the subgrade has a relatively high permeability value;

• the pavement is structurally adequate without drainage;

• lateral and vertical drainage in the pavement section exceeds infiltration; or

• ...

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