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4. Design a segmental masonry bridge of 25 feet span and formation 20 level 18 feet from bridge floor; and show on it (a) face wall, (6) blocking course, (c) impost, (d) starlings, (e) curtain wall, &c.
N. B.-Dimensions should be figured on plan, sections, and elevation.
5. Give neat figured sketches (elevation and cross-section) of a trape- 10 zoidal wooden bridge 30 feet span, and 20 feet wide, showing joints in the main girders.
6. Distinguish between plate iron and sheet iron, giving the grades in 10 thickness of plates; and state limit of area, and weight to which plates are ordinarily rolled.
Give easy rules to find the weights of bars, plates, &c., by reducing them to some uniform section or thickness.
7. Give sketches of the joints and the formulæ used to asce, tain the diameter of rivets for
(a) a single riveted lap joint;
(b) a double riveted lap joint; and
(c) a butt joint with two covers.
8. Describe wrought iron screw piles. In what circumstances are they used, and what is the arrangement of lengthening them and bracing them ?
9. Explain the principles of construction of the
(a) Suspension Bridge;
(b) Cantilever Bridge;
and state under what circumstances each may be employed.
WEDNESDAY, 20TH NOVEMBER.
[2 P.M. TO 5 P.M.]
CARPENTRY AND STRENGTH OF MATERIALS.
1. Describe with sketches:-Oblique Mortise and Tenon joint; scarf joint; stress; strain; modulus of elasticity; queen post truss.
2. Two teak beams 12 feet span, 12 inches deep, and 9 inches wide each; each beam supports 60 square feet of flooring, and the load may be taken as uniformly distributed. Find the greatest intensity of load to be put on the floor, taking f = 1,200 lbs. per square inch.
3. Draw a bending moment diagram and a shearing force diagram for 14 load on beam of No. 1. Give sketches with dimensions for a teak beam of uniform strength, when beam has (a) uniform depth 12 inches and (b) uniform breadth 9 inches.
4. King post truss-span 24 feet, rafters 30° to horizon, trusses 10 feet apart, tiles 60 lbs. per square foot, wind load 40 lbs. per square foot normal to rafter and on right side only. Find loads on all the joints.
5. Draw a diagram of loads for No. 4. Suppose right side fixed and left only supported, draw link polygon, and find supporting forces; draw diagram of stresses and mark amount of stress on each member of the truss.
8. Give sketches for a triangular truss for a bridge, say 40 feet span, all of timber, and loaded on lower flange. Show how you can arrange that (a) the verticals shall be struts and diagonals ties; or (b) verticals ties and diagonals struts.
6. Find suitable sizes for the members of No. 5, taking ƒ = 1,200 lbs. 14 per square inch with allowances for cutting at joints. Make a drawing of the truss to scale, with enlarged views showing how the joints are made.
9. What is the use of counter-bracing in a girder? Show how this would be applied to No. 8.
7. The left side of the roof of No. 5 is supported on cast iron columns, 10 one under each truss. Each column is 12 feet in height; find proper sizes, and design a suitable column.
THURSDAY, 21ST NOVEMBER.
[10 A.M. TO 1 P.M.]
2. Sketch and describe how you would arrange the rails at a point where two curves, in opposite directions, meet each other. Give a sketch of a check rail, and describe its use.
1. Derive the formula for super-elevation of outer rail; and find its 12 amount for gauge 5 feet 6 inches; speed 40 miles an hour; and radius of curve 2,000 feet.
What is meant by the tractive force of an engine? Find its amount 12 when-mean pressure of steam in two cylinders 120 lbs. per square inch; diameter of piston 12 inches; stroke 2 feet 6 inches; and diameter driving wheels 6 feet 3 inches.
4. For a railway single junction-main line straight, radius of crossing 12 rail 1,000 feet, gauge 5 feet 6 inches. Find position of heel and of actual point of switch; position and angle and spread of crossing. Sin 6·1045; cos 6° = 9945; cot 3° = 19.08.
5. What is meant by interlocking points and signals? Sketch and de- 10 scribe suitable arrangements for interlocking a set of points and two signals.
6. Show how you would fix on the ground the line and levels of a tunnel 10 about half a mile long with one shaft. Describe the operation of driving the heading, enlarging, and lining the tunnel with brickwork.
A masonry retaining wall, vertical and rectangular, supports a bank of 12 ; height 18 feet; angle of repose of earth 24°; masonry 140 and work 120 lbs. per cubic foot; sin 24° = 4.
d ratio of horizontal and vertical intensities of earth pressure; intenat base of wall; amount of horizontal pressure on one foot length of and moment of that pressure referred to base of wall; and
Find thickness of wall necessary for stability of position, taking 12 e of pressure at 3t from centre of wall; and show how the masonry is wall may be reduced without impairing its stability of position.
Taking the coefficient of friction for masonry as 6, find whether 12 two walls of No. 8, built with courses horizontal, have stability of tion; and if not, how may this be obtained.
THURSDAY, 21ST NOVEMBER.
SPECIFICATION AND ESTIMATING.
The accompanying drawing represents a small rest-house; stone walls; 50 ed roof: stone floor. 1
[See the Drawings facing this page.]
Take out quantities of all kinds of work in the building in the form of an timate and fill in price for each kind of work in Poona.
N.B.-Details of woodwork of trusses, and multiplications of dimensions need not be given.
2. Give short specifications for the following items of work in a bungalow o be erected in Poona; and give proportions, dimensions, and quality of naterials to be used:
(a) Excavating foundation trenches and filling them with concrete. 12 Depth of founds 10 feet in black soil which will not stand vertical.
(b) First class brick arches over doors.
(c) First class panelled doors 7' x 4'; noting thickness of frames,
(d) Double-tiled roofing-making notes about tiles, trusses, battens, 12 rafters, ceiling, wood work, iron work; the usual distances between trusses, rafters, battens should be stated.
(e) Wooden staircase 4 feet wide, giving names and dimensions of 12