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United States

Posted by admin on 13/ 11/ 15

The requirements for SMA binders used in the United States are related to the Superpave system prevailing in the country. The basis for the selection of binders for wearing courses, in principle their functional type (performance grade [PG]), is the climate of the given area of application. So all binders have to meet the same requirements for deformation resistance, fatigue, and low temperature cracking, but they meet those limits at different temperatures that relate to the climate in various parts of the United States. In specified situations, such as low-speed traffic or very high-traffic loads, the system additionally allows increasing the upper (high temperature) grade of the binder...

TOOLS FOR CHECKING LEVEL AND PLUMB

Posted by admin on 13/ 11/ 15

Checking for level and plumb are jobs a carpenter has to do every day. You don’t want floors running downhill or walls that lean. The tools used to check for level and plumb are levels and the plumb bob.

Levels

Although today there are many high- tech leveling devices that rely on lasers or microchips, the old standbys work quite well for most carpentry work.

Many carpenters carry at least two or three different sizes of spirit levels, and some still swear by water levels.

Spirit level The spirit, or carpenter’s, level is the best known of all. It is a simple tool consisting of a straight length of wood or metal with two or three glass vials located on it. Each vial is filled with spirit (like alcohol) so it won’t freeze, has a bubble in it, and is usually protected by a glass lens.

I ha...

Requirements According to European Standards

Posted by admin on 12/ 11/ 15

In Europe, road binders (paving grade) according to EN 12591 and modified binders according to EN 14023 have been used in SMA mixtures. Normally, road binders of 50/70 and 70/100 are used; however softer 160/220 types have also been cited in the regulations for roads with light traffic. The properties of each type of paving grade binder are fully specified in EN 12591; Table 5.6 shows selected properties of 50/70, 70/100, and 160/220.

European Standard EN 14023 for polymer modified binder (PMB) is similar to EN 13043 for aggregates. It comprises two tables with PMB properties to be chosen by any CEN country. In this way, PMB with the same designation could vary significantly from one country to another. Table 5.7 provides examples of some PMBs specified for SMA.

Recently, a technology ut...

NAILING STRUCTURAL PANELS

Posted by admin on 12/ 11/ 15

Your local building code will have the final say on sizing structural panels. To accommodate heavy loads, choose a panel rated for a higher span. A span rating of 32/16 indicates that the panel is strong enough to sheathe rafters spaced 32 in. on center and studs 16 in. on center and, therefore, can support far greater live loads than a 24/16-rated panel, even though a 32/16 panel is only & in. thicker.

Nailing schedules for different uses of plywood are the same: Nail every 6 in. around the perimeter, not closer than 3з8 in. to the edge; elsewhere, nail every 12 in. For subflooring, annular ring or spiral nails hold best; use hot-dipped galvanized nails for all exterior purposes. An 8d nail is sufficient for h-in. to M-in. plywood. For

Подпись: PROTIP Just one fragment from a nail head can blind you. So buy a pair of impact-resistant safety glasses that are comfortable— and then wear them. 1111 Подпись: Nail types. Top row from left: 60d galvanized spike, 40d common, 20d common, 16d galvanized, 16d common, 12d vinyl-coated sinker, 12d galvanized box, 10d galvanized common, 8d galvanized box, and 4d galvanized siding. Bottom row, from left: concrete nail and six joist-hanger and metal-connector nails (also called Teco™ nails). Longer nails may be required when sheathing covers framing. structural shear walls, follow the engineer’s sp...

REQUIREMENTS FOR BINDERS

Posted by admin on 12/ 11/ 15

SMA mixtures are chiefly laid as wearing courses. Binders for them should therefore have suitable properties for asphalt mixtures applied to that layer.

The majority of SMAs are placed in moderate climates. Therefore the SMA binder is usually an unmodified binder, or sometimes a polymer-modified one, with a penetration between 50 and 100 (0.1 mm) at 25°C. In several countries, multigrade

TABLE 5.5

Requirements for SMA Aggregates (Coarse, Fine, and Filler) in the United States

properties requirement comments

coarse aggregates

Подпись: Shape of particles: Flat and elongated, % (ASTM D 4791) Подпись: Particle surface. Crushed content:, % (ASTM D 5821) Absorption in water, % (AASHTO T 85) Susceptibility to weathering: Soundness, 5 cycles, % (AASHTO T 104) Подпись: Susceptibility to weathering: Soundness, 5 cycles, % (AASHTO T 104) Angularity, % (AASHTO T 304, method A) Atterberg Limits Tests Liquid limit, % (AASHTO T 89) Plasticity index (AASHTO T 90) <30 There is a suggestion to use additional test

methods like Micro-Deval or SGC degradation test. Despite experiences with aggregates of LA 30-45%, their use is not recommended due to possible grain crushing during compaction both in the laboratory and on the road.

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Special Project Procedures

Posted by admin on 12/ 11/ 15

Healthy home building does not permit many behaviors and practices that are commonly accepted at standard jobsites. The procedural expectations must be clearly stated by the owner and upheld by the contractor. Some basic rules that you may wish to include and expand upon in your specifications are: [1] [2]

contamination and moisture damage during storage and after installation.

Pads are poured

Posted by admin on 12/ 11/ 15

It’s common practice to pour any pads required in the plans at the same time the footings are poured. In a crawl-space foundation that includes a post-and-girder framework, poured concrete pads provide a base for concrete piers and wood posts (see the illustration on p. 48).

A common size for these pads is 16 in. square by 8 in. deep. If you’re building a basement foundation, pads are also required to support each post or Lally column. These pads are poured below the level of the basement floor and will be covered when the slab floor is poured. If a wall will provide midspan support for joists, a continuous footing is poured instead of separate pads.

STEP 2 BUILD THE FOUNDATION WALLS

The house shown here has concrete block walls...

MARKING TOOLS

Posted by admin on 12/ 11/ 15

A carpenter uses many different tools to mark all kinds of materials: wood, Formica, drywall, concrete, tile, you name it. Most of this can be done with a few basic marking tools, such as pencils, keel, pens, chalklines, and dryline.

Pencils, keel, and pens

While many lumberyards give away standard pencils, flat-sided carpenter’s pencils are more durable, easier to sharpen with a utility knife, and won’t roll away when set down on a board.

Keel (commonly known as a lumber crayon) is easier to see than a pencil on some surfaces, making it better for some kinds of layout work. Blue and red keel show up well on rough lumber and concrete; white works best on new concrete.

A few specialty pens are also useful on the job site...

Requirements

Posted by admin on 12/ 11/ 15

Statement of Intent

Clear communication among contractor, owner, and architect is a key factor in the success of any building project. When creating a healthy home, there are many special project procedures that must be communicated with even greater clarity than in standard construction. The owners intentions and instructions for special procedures can be formally transmitted in the statement of intent, thus making them part of the construction contract.

Here is a sample of specifications language that succinctly states the owners wish to create a special project:

This house is being constructed as a healthy house. The following specifications outline special project procedures and acceptable building products...

CHOOSING A FOUNDATION

Posted by admin on 12/ 11/ 15

Foundation types vary by region. When deciding which type of foundation to use, consider the cost, climate, and local preferences. The three major foundation types are discussed here.

Concrete Slab

Подпись: PT sill Подпись: 4-in. (minimum) reinforced slab, continuous with footing Подпись: Footing extends below frost line. Подпись: Moisture barrier Подпись: 4 in. (minimum) of compacted gravel CHOOSING A FOUNDATION Подпись: Termite shield Slab foundations are popular throughout southern sections of the country and in regions where winter temperatures are mild. A concrete slab is more than a foundation; the slab also serves as the rough or finished floor for the first level of the building. This explains why slab foundations are less expensive than other types. Because concrete has poor in – sulative qualities, slab foundations are often insulated with rigid foam. Plumbing waste lines are typically cast into the slab, so they must be carefully laid out and installed first...