Study.

What factors influence the design of a cross section?

Batter Slopes, Geology, Soil type and stability, balancing cuts and fills.

What are batters slopes in a cross section?

Batters are man made slopes which join the edge of the road work to the natural surface. Their slope depends on the geology, soil type and stability of the soil.

What effect do horizontal curve and vertical curves have on volume calculation when using cross section area?

Cross sections are not parallel volume calcs by using one of the formula (mean, end, prismodial) rely on a fixed distance between stations. Thus volumes may be under 0. Over estimated. need to find the centroid of the the cross sections to determine the "morlified" cross section areas and use them in volume calcs. Vertical Curves minimal or zero effect.

What are cross sections and when are they taken?

Cross sections are regular views taken across the center line of a road. Enable us to see what is happening either side of the center line. Usually taken at intervals, or when their is usually profile.

What is chainage?

Distance along the centerline of a road or other section.

Describe how optical plumbing techniques could be used to control the verticality of a building under construction?

An optical plumbing device or optical plummet of theodolite can be used to plumb upwards or downwards. Holes opeings in floors are required. Centiring devices located on floor which allow measurements to be made to outside.

Given a typical cross section for a road, describe some methods you could use to determine it's cross sectional area.

Area by graphical methods -Counting Squares. -Dividing area into square/triangles. Calculation: -Divide area into triangles & measure sides & then calculate. -Offset areas from axis through area. -By coords, give coords to all corners & use equation. Planimeter -Mechanical device, trace the outside.

Outline the various techniques which could be used to transfer heights up to 10 meters or more story building during construction.

.Weight steel type. .Establish temporary bench marks on floors. .Electronic distance measurement but measuring vertically with appropriate optical leveling devices.

A road cross section has been drawn on graph paper, and the cross section was measured to be 300 square millimeters. The horizontal scale of the cross section plot was 1:200 and the vertical scale 1:50. What the actual value of the cross sectional in square meters?

300 * 200 * 50 3,000,000 mm^2 = 3m^2

What is invert level and why is it important in drainage design?

Invert level is the RL of the bottom inside of a pipe. Important for making water travel down, need to insert the next invert lower than the previous one.

What methods could be used to check the vertical alignment of a high story building?

Plumb bob Methods Theodolite Methods Optical plumbing Plumb suspended on wire, bobs suspended in drum of oil, holes in floor allow plumbline to be vertical. Theodolite Use telescope to test verticality. Optical plumbing-Use optical plummet to plumb upwards/downwards needs openings in floor.

Why are recovery marks needed in construction site? Explain how these marks are related to control marks and to other "peg-out" marks?

Recovery marks needed because other marks (construction pegs) may be destroyed during construction or vandalised removed unable to set up on etc. Peg out marks assist in the construction and setting out of works. They may be lost. Need control marks to easily re-establish these marks. Recovery marks are backups, just in case the control marks are lost.

What are sight rails and travellers?

Sight rails are fixed stakes which form some pre determined hieght. Trevellers are set at some pre determined height for excavation. Travellers used with sight rails, but can be moved and are sighted between sightrails to determine specific depth or height relative to the height of the sight rail.

What methods are for vertical control?

Temporary bench marks: Temporary bench marks can be established on site, but should be stable and secure. Sight Rails: Consist of a piece of timber attached horizontally to one or two vertical stake the top of the rail is usually set at some convenient height. Travelers: Travelers are used with sight rails, where the traveler is sighted between the sight rails to check on the amount of excavation. Slope rails or batter boards: slope rails or batter boards are used to control or resemble sloping profiles. They indicate the position and gradient of a cutting or embankment side slope. Profile Boards: Profiles consist of a horizontal cross piece fixed to two stakes with a nail or saw cut indicating the construction line. Profiles are set back from the construction. A builders line can be tied between the profile marks.

What is invert level?

The inside of bottom of a pipe.