Blog Archives

Laying out the ridge board

Posted by on 22/ 11/ 15
Подпись: 2x10 ridge board

Rafters cover the joint between ridge sections

Ridge board ripped to width of barge rafter in overhang ‘

Подпись: Gable-end rafter 2×8 common rafter

Подпись:

every 1 б о. c. or 24 in. о. с. If more than one board will be used to make up the ridge, cut the boards so that each joint falls in the center of a pair of rafters. Be sure to align the layout of the ridge board to that of the joists so that the rafters and joists tie together at the plate line. If both are spaced 16 in. o. c., every rafter will tie into a joist (see the draw­ing on p. 142). If the joists are 1 б in. o. c. and the rafters are 24 in. o. c., a rafter will tie into every fourth joist.

Some builders like to let the ridge board extend out into the overhang and catch the ends of the barge rafters (see the drawing on the facing page)...

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Characteristics of the SMA Course

Posted by on 21/ 11/ 15

Constituent materials, design, production, and placement of a stone matrix asphalt (SMA) mixture were discussed in previous chapters. It would not make sense to spend this much time discussing the mix if SMA courses had not been characterized with many strong points. Conversely, it should be openly admitted that it is not a perfect mixture, and it also has a couple of run-of-the-mill or slightly poorer proper­ties among some very remarkable and even outstanding ones. In any case, its lack of perfection does not affect the final appraisal of SMA as a very useful material for pavements. After all, the rapid increase in SMA applications all over the world has not been exclusively brought about by fashion.

Next, the following operation and maintenance properties of SMA courses will be elabora...

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OVERDOSAGE OF AN ANTISTRIP ADDITIVE

Posted by on 21/ 11/ 15

It happens occasionally that an additive dosing system does not work correctly. When that happens, there is either too much or too little antistrip additive in the mixture. Its deficiency does not directly affect the quality of the mixture during production or placement. Effects may appear in the form of a lower durability of the course under traffic. However, an excess of the antistrip additive can manifest itself in an imme­diate and direct impact on the quality of the mixture. Usually the antistrip additive overdosage may be identified while still in the batching plant because of the charac­teristic (i. e., unpleasant) smell of the mixture...

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Sma susceptibility to polishing

Posted by on 21/ 11/ 15

Although susceptibility to polishing is not a problem at the construction stage but a result of an earlier decision, greater pavement slipperiness becomes apparent after some time of pavement operation. The source of this problem is at the design stage of an SMA composition. The proper selection of an aggregates for a mixture and the level of designed air voids content are crucial.

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FIGuRE 11.34 Mastic squeezed-out of SMA in wheel paths during trafficking of pave­ment. (Photo courtesy of Krzysztof Blazejowski.)

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FIGURE 11.35 Polished SMA surface after 3 years of operation. (Photo courtesy of Krzysztof Blazejowski.)

We may define the expected scope of an aggregate’s polishing resistance for wearing courses through the selection of the polished stone value (PSV) category...

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Installing a Granite Countertop

Posted by on 21/ 11/ 15

Once you’ve looked at granite samples and narrowed your choices to a few varieties, consult the fabricator—the company that will be cutting and installing your stone.

For example, if you choose a granite with large crystals, joints between sections may be more obvious than those between finely grained stone. Besides, some richly figured stones are more likely to crack or spall when subjected to everyday use. A fabricator’s practical concerns can be a good counterpoint to a kitchen designer’s artier point of view. In any event, cabinets and the plywood substrate must be installed before measurements for a stone countertop can be made.

1. Подпись: sink to hundreds for a custom-made, 16-gauge commercial-grade sink with multiple bowls. ► Enameled cast-iron or enameled-steel sinks are available in numerous colors and provide a classic look that works in modern and traditional kitchens. Enameled sinks have a hard finish; but the enamel can chip, making the metal substrate likely to rust. Abrasive Подпись: 2. After ensuring that the substrate is flat, installers typically lift the slabs, stand them on edge, and carefully lower them into position to test clearances, cutouts, overhangs, and so on.

Подпись: 4. After caulking the undermount sink with silicone, installers set the slab on the epoxy grid. To avoid spreading the epoxy too thin, installers don’t slide the stone in place—they lift and lower it as close to the final position as possible. Suction-cup handles help. Подпись: 5. After leveling the slabs, pros ensure that the joint are flush by sliding a razor blade back and forth acro; them. If one side is higher, the razor blade clicks as it hits a high point or falls from a high point to a low one. More sensitive than a fingertip!
Подпись: . .УЖ

An experienced installer takes nothing for granted and will scrutinize substrates for high and low spots before anything else...

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ORDERING COUNTERTOPS

Posted by on 21/ 11/ 15

Once you’ve identified several reputable coun­tertop shops in your area, get bids. For your protection, develop detailed floor plans and, as you proceed, put everything in writing. That way, you’ll be sure that quotes from different shops reflect similar details, deadlines, and so on. The following guidelines are adapted, with permission, from Sullivan Counter Tops, Inc. (visit www. sullivancountertops. com).

Visit suppliers in your area. Look at counter­tops in several different showrooms, and discuss your options with the salespeople. Share any information—samples of wall paint or cabinet finishes, magazine ads showing counter surfaces, photos of sinks or sink fixtures—that will clarify the style and look you’re after...

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In-Situ Results

Posted by on 21/ 11/ 15

The deterioration of strength, stiffness and resistance to the development of per­manent deformation, or the reduction in pavement life, with increasing moisture levels is a common observation. Trial pavement studies in which the water content of the construction has been changed and reduced performance observed are quite numerous. In recent years work in Finland has been reported by Korkiala-Tanttu and Dawson (2007) showing the much faster rutting of a test pavement with a high water table than one in which it was lower. In an earlier study by accelerated trafficking, Vuong et al. (1994) found that the life of a crushed-rock base was very dependent on the degree of saturation in the aggregate base course...

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Plank and Beam Roofing

Posted by on 21/ 11/ 15

“Plank and beam” roofing consists of planks — often tongue-in-groove — supported from below by exposed beams, or rafters. This is the system we used at Log End Cottage, Log End Cave, and Earthwood, and it is my favorite roof support system for three reasons:

i. We like the aesthetic appeal of exposed beams, with light- colored V-joint tongue-in­groove planking above them.

Fig. 4.46: The trusses are temporarily stored upside down, straddling the sidewalls.

 

image90

image91Подпись: 2. Plank and beam roofing is strong. For example, two-by-six tongue-in- groove planking — on four-foot centers — will support a 185 PSF (pounds per square foot) earth roof load, providing that the beam framework is engineered correctly. With conventional roof loads, planking spans of six feet and even eight feet are possible. Fig. 4.52 shows a strong homemade truss system, with the tension and compression web members sandwichedFig. 4.47: Chris started with the second truss from the end, well braced to the ground. The first and last trusses, called the gable trusses, have overhangs built into them, which makes them more difficult to deal with. After all the other trusses are braced firmly in place, the two gable trusses are installed...

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Slip Base Designs

Posted by on 21/ 11/ 15

Slip base designs for multiple sign supports are usually of horizontal design as shown in Figs. 7.23 and 7.26. Horizontal slip bases, when used in multiple-sign-support systems, operate satisfactorily when impacted from only one direction. Horizontal slip bases should not, therefore, be used for multiple sign supports where there is a high probability of impacts from more than one direction. In Fig. 7.26, the keeper plate prevents the bolts from “walking” out of the assembly as a result of wind vibration (Art. 7.4). The washers should separate the upper and lower slip plates by at least И in (3 mm), but not more than И in (6 mm), to prevent mating of the surfaces and possible binding due to friction...

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Protection from Decay

Posted by on 21/ 11/ 15

Moisture and warm air are catalysts of fungus, which causes dry rot that can destroy a building.

In addition to calling for ventilation to control moisture, the code also requires decay-resistant wood wherever moisture can come in contact with structural wood. Some areas of the country are more conducive to decay than others. The code requires naturally durable wood or preservative-treated wood in the following situations:

• Wood joist or the bottom of the wood floor structure if less than 18" from exposed ground. (See “Joists & Girder Protection" illustration.)

• Wood girders if closer than 12" from exposed ground.

• Wall plates, mudsills, or sheathing that rest on concrete or masonry exterior walls less than 8" from exposed ground...

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