Choose correct variant of terms to following definitions

1. This kind of wall is strengthen by the introduction of the certain type of metal in the form of bars, wire etc.

a)cavity b)rubble c)reinforced brickwork

2. It is built of thinly-bedded stone

a) rubble b) partition c) ashlar

3. It consists of two separate walls with a cavity in the middle

a) ashlar b) block-in-course c) cavity

4. It is composed of squared stones

a) partition b)block in course c) ashlar

5. They are used as deep trusses for supporting parts of a building

a) cavity b) partition c) rubble

Discuss with your group mates peculiarities of all types of walls, positives and negatives for the certain kind of building and its parts

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Find correct translation to Russian words. Explain their meaning in English

Compose correct word combinations from both columns. Try to guess their meaning

single-joisted joists

double-joisted supported

triple-joisted floor

single brick

basement wood slab

bridging beam

binders

perforated

filler

fire-resisting

ferro-concrete

hollow

precast

Read the text. Find synonyms characterizing all kinds of floors

Floors

Definition. —The tiers or levels which divide a building into stages or stories are called floors. These may be of timber, or they may be constructed of fire-resisting materials.

Classification. —Floors for ordinary residential purposes are mostly made of timber, and may be divided into:

Single-joisted floors include bridging joists.

Double-joisted floors include bridging joists supported by binders.

Triple-joisted floors include bridging joists supported by binders the latter usually being framed into girders which finally support the load.

Single Floors. —When the total weight upon a floor is carried by a single system of joists, which span or bridge an opening, it is termed a single floor, and the joists are known as bridging joists.

Basement Wood Floors. —Basement floors constructed of timber are subject to rot unless adequate precautions are taken to keep the woodwork dry and well ventilated. To attain the latter conditions and also to comply with general hygienic requirements, the soil below the basement floor should be covered with 6 inches of good concrete, gauged and graded to be practically damp proof. A composition of 1 part Portland cement, 2 parts sand and 4 parts broken ballest will give good results and keep down dampness when not under pressure and also ground air.

Double Floors. —Where the smallest span exceeds I5" feei it becomes economical and better construction to employ double floors. These consist of girders usually placed across the shortest span, and joists crossing them at right angles and fixed in the direction of the longest span.

Triple-joisted Floors. —For spaces of 25 feet and over in timbers, the main girders require lateral support. Intermediate beams known as binders are framed into the main girders, and these in turn support the bridging joists. Large wood floors of this type are now obsolete, owing to the difficulty in obtaining timbers sufficiently large for the main girders and also from the combustible nature of the material. Where floors of this type are employed, the main girders would always be of steel, either simple rolled beams or compounds, according to the nature of the loads to be supported. The proper necessary ventilation may be obtained by the insertion of iron or terracotta air bricks at intervals in the outer walls between the ceiling and the floor boards level, and by boring a number of horizontal holes through the joists at the centre of their depth, by using ceiling joists, or by brandering, so that.the air may circulate through all. The ventilation is more complete, when, instead of a few iron or air bricks, a course of perforated bricks is inserted at two or more sides of the floor, and provision is made for a thorough ventilation without draught.

Fire-resisting Floors. —The practice of employing a system of fire-resisting construction for floors in all cases where it is not imperative to reduce the initial cost to the lowest point is now becoming universal. Some of advantages of this form of construction are safety from fire, its superior hygienic properties, and ease with which floors of wide spans may be constructed thus enabling any storey to be divided into rooms, without reference to the arrangement of the rooms either above or below.

Upper Floors. —There are a large number of patents for the construction of upper floors, but they nearly all conform to one of four types, i. e., 1) filler joists, 2) ferro-concrete slabs, 3) hollow block and rib, and 4) precast beams, each of which is a method designed to support the essential con­crete slab.

Filler Joist Floor s. —In this type of floor the concrete slab is reinforced with rolled steel joists of small section, spaced at from 2 feet to 3 feet centres and in spans up to 20 feet. The filler joists may rest on brick walls or cleated to main steel girders.

Ferro Slab Floor s.— The floor surfaces in this type are formed of concrete reinforced with steel rods spaced at about 6 inch centres. The minimum thickness permitted for floors is 3 inches, but generally they run aboutinch in thickness for every foot of span.

Hollow Block Floors. —These are formed of hollow earthenware or terra-cotta blocks from 9 inches to 1 foot in width, about 1 foot in length, and of a depth varying from 6 inches to 1 foot. They are laid in parallel rows on the formwork, their ends butted, and with a space between them of from 4 inches to 6 inches wide.

Precast Beam Floor s. —These consist of hollow precast reinforced beams of about 10 inches in width, and a depth varying to the requirements of the load and span. They may be supported direct upon walls or be placed between steel joists. The sides are grooved to form joggles. The beams are precast, and seasoned before delivery, and can be lifted and bedded in position directly, and the surface concrete screeded on direct.

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