Masonry arches

Just about every bearing wall has utilities buried within it. It is not uncommon to find plumbing supply and wastes lines, heating and cooling ducts, electrical wires, and low voltage wires for telephones, doorbells, and intercoms. It is possible to relocate these utilities in almost every case, however, it may be time consuming, costly, and require extensiveadditional demolition.

Load bearing walls often run perpendicular to the run of floor or ceiling joists that rest on top of the wall. However, beware of walls that run parallel with floor joists. They can obscure hidden posts or columns. One can create an opening in a bearing wall much the same as openings are created in exterior walls for large windows or doors. A beam is placed over a new opening. The beam accepts the load from above and concentrates it onto columns or posts at either end of the beam. The new columns or posts that support a new beam must rest upon solid bearing material. The weight of the structure above the beam will then be transferred to a spread footer, thickened slab, steel or wood beam, or possibly some other structural member below.

REMOVING A LOAD BEARING WALL

ТИПИЧНЫЕ ОШИБКИ, ДОПУСКАЕМЫЕ ПРИ СТРОИТЕЛЬСТВЕ СТЕН

При возведении стен проблемы возникают довольно часто. В первую очередь нужно внимательно отнестись к материалу и подходить к его выбору основательно и не торопясь, поскольку в зависимости от этого вы можете получить тот или иной букет «случайностей».

Предположим, вы всегда мечтали иметь деревянный дом и наконец-то приступили к постройке. Учли ли вы, что дерево требует дополнительной обработки вовремя и после возведения из него стен? Если не применить специальные препараты, то ваши стены станут прибежищем насекомых, которых вытравить будет довольно трудновато, а ведь они не будут мирно радоваться новоселью, а станут поедать древесину. Ещё более важной проблемой может стать горючесть дерева как материала, поэтому его так же стоит обрабатывать уже другими специальными препаратами. Как ни странно, про эти сложности забывают.

Кирпичные стены таят в себе другие неприятности. Примером таковых может служить появление белых разводов соли на стене, явления, связанного в основном с частыми и значительными перепадами температур. Прежде чем закупать кирпич для постройки, стоит основательно вникнуть в «разнообразие видов». Предлагаемый ассортимент довольно велик, и у каждого вида есть свои достоинства, впрочем, как и недостатки, а верный подбор минимизирует возможные проблемы. Оштукатуривание фасада здания сложенного из кирпича также таит в себе несколько проблем, которые упорно не замечаются до их явного проявления, хотя большинство из них можно избежать на стадии планирования. Например, фасады покрытые штукатуркой по мокрой технологии могут быть долговечными разве что в южных краях. Следствием чего станет необходимость не просто постоянного подновления, а конкретно основательного ремонта. Не забывайте соблюдать пропорции приготовления цементно-известкового раствора: стены не должны быть ни сырыми, ни пересушенными, толщину штукатурного слоя нужно рассчитывать, а не просто наносить и т.д.

(www.domaderevo.ru.)

19 Read the text. Discuss the problem raised in the text with your partner. Use the linking words/phrases from Appendix 1:

Sizing the beam and posts that support the beam should be done by a professional. A structural engineer is trained to calculate the current floor, ceiling and roof loads and possible added loads caused by snow, attic storage, and additional roof coverings. If to undersize a beam, portions of the house may sag and even in extreme cases collapse. The fee to hire an engineer who can develop a re-support plan in minuscule compared to the cost of repairing structural damage after a collapse.

There are several different ways to install a new beam in a load bearing wall. In some instances the beam can be hidden within the ceiling above. This works if the beam height does not exceed the height of the floor or ceiling joists and there are no utilities that must pass through a new beam location. If to choose this method, the floor/ceiling joists above are attached to a new beam using metal joist hangers.

The most common approach is to install a new beam bellow the floor/ceiling joists. To install a beam one need to build a temporary support wall on either side of the wall which is being removed. The temporary walls should be held back about 30 inches from each side of the old wall. Be sure to build a new beam and slide it up against the old wall before to build a last re-support wall. If to fail to do this, it is often impossible to get a new beam into position.

One can often see where these utilities enter the bottom of the wall in a basement. In some instances, wires and plumbing vent pipes might be visible in an attic as they rise up from the bearing wall. It is better to use an electronic device made specifically for this purpose, for example, hand held devices with a liquid crystal screen that will show studs, hidden pipes, wires, conduits, and duct work. These units can “see” through plaster, drywall and wood.

(By Tim Carter; ©1993-2012 Tim Carter)

20 Study the information bellow, find additional information and speculate on the problem raised in the text. Use the linking words/phrases from Appendix 1:

The arch has long been used in masonry structures. In fact, a brick masonry arch found in the ruins of Ur in Mesopotamia dates back to 1400 B.C. Today, the brick arch is used in construction to span over wall openings and add aesthetics, as the arch is the consummate definition of form and function.

This information addresses design considerations for brick arches in veneer construction. Common arch terminology is shown in Figure 1. below. The first important consideration when designing a brick arch is whether the arch is structural or non-structural. That is, will the arch be required to transfer vertical loads to abutments or will it be fully supported by a steel angle. While this may seem obvious, confusion often develops because of the many configurations of arch construction.

To answer this question, one must consider the two structural requirements necessary for a brick arch to adequately carry vertical loads. First, vertical loads must be carried by the arch and transferred to the abutments. Second, vertical load and lateral thrust from the arch must be resisted by the abutments. If either the arch or the abutment is deficient, the arch must be considered as nonstructural and the arch and its tributary load must be fully supported by a steel angle or plates. Alternately, reinforcement may be used to increase the strength of either or both the arch and the abutments.

This main concept in masonry arch design is overlooked, ignored or just simply not understood by nearly all home builders. Home owners ignore the problem of a failing arch only to later physically watch as these arches fall to the ground dramatically increasing the cost of repair. This defect in masonry construction is growing worse each year as fewer and fewer of today’s homebuilders or masons receive any vocational training or apprenticeship in the field.

(www.themasonryarch.com)

21 Topics for projects and presentations:

1. Modern tendencies in interior wall construction.

2. Modern tendencies in exterior wall construction.

3. Wall construction types: advantages and disadvantages.

4. Decorative exterior walls.

5. Walls in popular culture.

“The two most important keys to effectively organizing a floor plan are

managing solid-void relationships and resolving circulation.”

MatthewFrederick (architect)

Дата добавления: 2014-11-29