Blog Archives

Development of the Roman Orient

Posted by on 20/ 11/ 15

During the last years of the Republic, Greece, Anatolia, Syria-Palestine, Egypt, and Cyrenaica had become Roman. This process began with the bequeathing of Pergamon to the Roman Republic, and was marked by Augustus’ taking possession of Egypt in 31 BC, and continuing through the tumult of the many wars during the last years of the Republic. There is not much to say of Greece, for she was knocked flat by wars and never got back on her feet economically. The reader may recall the development works at lake Copais undertaken in the Mycenaean era (Figure 4.10), and somewhat restored by Alexander the Great. Several sources mention that during the Roman period the lake’s dikes are no longer maintained, that the adjacent cities are subject to flooding, and that the best land must be abandoned.

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Sign Components

Posted by on 20/ 11/ 15

Sign assemblies consist of four components:

• The sign panel on which the message is displayed

• The signpost

• Mounting hardware and fasteners

• The base for the post

Sign Panels. The majority of sign panels in use today are made from sheet alu­minum stock [19]. The thickness of the stock varies depending upon the sign size but is generally not less than 0.16 in (4.0 mm). Plywood is occasionally used by some agencies as the blank material for the reflective sheeting face in areas of frequent van­dalism due to gunshots. Wooden sign blanks deform less from gunshots, are easier to repair, and are not as attractive a target as aluminum sign blanks. Plywood, however, does not weather as well as aluminum and, if the edges are not sealed correctly, has a relatively short life...

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DESIGN OF SINGLE-MOUNT SIGN SUPPORTS

Posted by on 20/ 11/ 15

Traffic signs are a primary source of information to motorists. The majority of traffic signs consist of sign panels held in place by a single support. Single supports can usu­ally be used for signs as large as 18 ft2 (1.7 m2) in area. The only purpose of the sign support is to hold the sign at the proper position for driver visibility. This requires that this support be strong enough to maintain the sign panel in its intended position while subjected to wind, ice, and snow loads. The magnitude of these forces increases as the sign panel becomes larger in size, until the panel is so large that multiple supports are required. Single sign supports are made of different materials, of various sizes and con­figurations, each capable of withstanding different environmental loads...

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Wall Framing

Posted by on 20/ 11/ 15

Stud spacing should be shown on the plans, but it is still good to be familiar with the code limitations. For 2 x 4 studs less than 10 feet tall, the maximum stud spacing is 24" O. C., provided the wall is supporting one floor or a roof and ceiling only. For the support of one floor, a roof, and ceiling, 16" O. C. is the maximum. To support two floors, a roof, and a ceiling with a maximum spacing of 16" O. C. and height of 10′, a minimum of 3 x 4 studs must be used. If studs are 2 x 6, a wall can support one floor, a roof, and ceiling at 24" O. C., or two floors, a roof, and ceiling at 16" O. C. Again, this stud spacing only applies to walls that don’t exceed 101 in height. (See "Stud—Spacing and Size" illustration.)

Cripple walls less than 41 in height should be framed with studs at lea...

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Making It Happen

Posted by on 20/ 11/ 15

IMAGINE MARION WILLOUGHBY,

sitting on the rotting front porch of his leaking rental house, listening to Habitat’s offer to have volunteers help him build a new home. Imagine him hearing that Habitat will sell the new house to him at cost and also give him a mortgage with 0% interest.

Marion did not believe a house could be built in just one week. But his opinion began to change when he saw the Habitat volunteers arrive in the pouring rain with a 40-ft. horse trailer packed with enough gear for a

crew of 30 members. Marion began to believe that a miracle might happen in just six days.

I can’t count how many times that week he said, “You don’t see ladies doing this kind of work!” and “This is such a blessing!” and “You people do it right!” Marion was amazed that a crew of accountants, lawy...

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Irrigation works in North Africa

Posted by on 20/ 11/ 15

Lucius Septimus Severus was born at Leptis Magna, capital of Cyrenaica (today’s Libya), at the end of the 2nd century AD. After the death of the Emperor Commodius in 192 AD, Severus emerges victorious from the civil wars, and becomes emperor in his turn, founding the dynasty of the Severians. North Africa had already been a prosper­ous region for some time; we have mentioned earlier the great aqueducts of Carthage and Cherchell (Lol Caesarea), testaments to the prosperity of these cities. But the new emperor adorns North Africa even further, battling the desert nomads, building roads and fortifications, and creating the new province of Numedia to the west of present-day

Tunisia...

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BUILDING OUT FROM THE MAIN DRAIN

Posted by on 20/ 11/ 15

Extending the DWV system out from the end of a cast-iron main drain—where it joins the soil stack—can be the least disruptive way if there’s a cleanout at the end of the drain that you can remove. Before cutting the drain, support both sides of the section to be cut, using pipe clamps or strap hangers.

The exact configuration of the end run will depend on the size of the main drain, the fitting currently at the base of the stack, the fixtures you’re adding, and the size of the drain needed to serve them. If you are not adding a toilet, the drain extension can be 2-in. pipe, which can be attached with a reducing bushing such as the male-threaded adapters shown in "Extending with 2-in. ABS,” at left. If you’re adding a toilet, however, the extension must be 3-in...

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Toe-nailing and Toe-screwing

Posted by on 20/ 11/ 15

Nails, when they became cheap, replaced dowels, doveta Is, and mortise-and-tenon joints. Most nailing is called surface nailing: driving a nail straight through one board in order to fasten it to another. This is the way roofing planks and plywood are installed, as well as wooden siding.

But one of the most valuable skills in timber framing for the rest of us is to learn how to toenail properly. A toenail (in carpentry) is a nail driven at an angle that allows us to join one timber to another where they meet at right angles. It is a fairly strong method of nailing, because toenails are always installed opposite each other, as in Fig. 4.21. Some of the nails will always provide shear strength, no matter which way a timber is forced...

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Resilient Behaviour

Posted by on 20/ 11/ 15

9.4.1.1 Routine Pavement Analysis

In practice much routine pavement design is carried out as catalogue-based design. Nevertheless, routine structural analysis and design methods are used as supple­mental design methods where the pavement is considered as a multi-layered elastic system (Amadeus Project, 2000). The layers are characterised by Young’s modulus, Poisson ratio and thickness. The simplest model for the stress-strain behaviour of isotropic materials is based on linear elasticity, which is described by Hooke’s law. In two or three dimensions, the model is written:

°ij = Ejr (9.1)

where oij, ей, Eeijkl are respectively members of the stress, strain and stiffness tensors а, є and Ee.

A symmetric stiffness matrix is used to describe the constitutive equations in those cases...

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Lay out and cut the stringers

Posted by on 20/ 11/ 15

There are two basic types of stringers for stairs. Cut, or open, stringers have square cutouts to support treads and risers. Closed stringers use cleats rather than cutouts to support treads. To

Подпись: Use a square to lay out a stair stringer. Mark the square cutout areas with a framing square. The tread and riser measurements on the square align along the edge of the board.

give a deck or porch stairway a trim look, I like to use closed stringers on the sides. Cut stringers must be used in the middle. Stringers for out­door stairways are usually cut from PT 2x12s. Stairs with three risers can be cut from 4-ft. stock, but it’s a bit tight. Stairs with four risers can be cut from 6-ft. stock.

A framing square and a pencil are all you need to lay out stair stringers. Although they aren’t necessary, a pair of stair gauges (small clamps that screw onto a framing square) make the layout process faster and just about fool­proof. Attach one gauge at the 71/2-in...

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