Challenge 2

1. Spread Foundation

The spread foundation is additionally called an open foundation and is reasonable for bridge foundation of normal tallness based on a firm and dry ground to offer help for the construction. This types of bridge foundation is appropriate where there is least scouring and the hard grounds starts from 1.5m – 3m underneath the level of the watercourse.

2. Raft Foundation

These types of bridge foundation are generally utilized where there passable bearing limit of the soil is less and the watercourse bed contains delicate clay and silt. It favors foundations where hard soil isn’t found inside sensible profundity of 1.5m – 2.5m, beneath the watercourse.

3. Pile Foundation Bridge

PILE FOUNDATION is the types of bridge foundation that is utilized in conditions where there is extremely delicate soil and hard strata are not accessible at a sensible profundity. It is likewise utilized where scouring of a river as to be done and a enormous concentrated load is to be taken by the foundation.

4. Well Foundation Bridge

WELL FOUNDATION of bridge is the types of bridge foundation that is utilized when the bed has SANDY SOILalso, hard soil is accessible at 3 – 4 m beneath the level of the watercourse. Most appropriate on soil a cotton having delicate soils what’s more, sandy soils and weighty scouring is relied upon due to the huge velocity of approach of the river.

5. Caisson Bridge Foundation

CAISSON BRIDGE FOUNDATION is a types of bridge foundation that is utilized where there is a hard layer close to the river bed and there is exorbitant water profundity that isn’t monetarily strong to eliminate the empower sinking wells for well foundation.

6. Grillage Foundation

This types of bridge foundation is reasonable for weighty and separated footings of wharfs where deep foundations are to be stayed away from. GRILLAGE FOUNDATIONis most appropriate where sub soil conditions are poor.

7. Inverted Arc Foundation

This types of BRIDGE foundation is appropriate when the profundity of unearthing for foundation is less. ARCH BRIDGE s most appropriate where the bearing limit of the soil is less, particularly when the sub soil has some delicate pockets and there is plausibility of inconsistent settlement.

superimposed dead load is the dead load on the structure after slab and beams have been casted .. dead load is the load from slabs and columns and beams.

superimposed load: The load superimposed on the dead load of a building. The term is generally synonymous with live load, although a distinction is sometimes made between the superimposed dead load caused by movable partitions, etc., and the live load caused by people.

1. What are the different types of girders that can be used for a metro viaduct?

ans- Use U type girders in metro viaduct

I GIRDER UESD IN METRO VIADUCT

BOX GIRDER USED IN METRO VIADUCT

BUT U GIRDER USED METRO IN BECAUSE IT PROVIDE SAFTY AND BENFICIAL FOR METRO

4.What are bearings in a metro viaduct. Explain the types of bearings and analyses the types with respect to their advantages and disadvantage.

5.During the construction of metro viaducts across water passages, explain the topographical check list that needs to be considered for the designing the height of the viaducts?

ANS- The piers, two in number having a height of 24 metres from its base and a diameter of two metres.

and 27 metre when constructed the metro viaduct

2. Types of Topographic Surveys
Topographic surveys are performed for the master planning, design, and
construction of installations, buildings, housing complexes, roadways, airport
facilities, flood control structures, navigation locks, etc. Some of the more common
surveys are described below:
2.1 General/Preliminary Site Plans
General or Preliminary site plans shall performed at scales from 1:2,000 to 1:5,000.
They depict general layout for potential construction, proposed transportation
systems, training areas, and existing facilities.
2.2 Detailed Topographic Surveys for Construction Plans
These surveys are performed at scales from 1:200 to 1:2,000 and at varying contour
intervals. They are performed to prepare a base map for detailed site plans (general
site layout plan, utility plan, grading plan, paving plan, airfield plan, demolition plan,
etc.). The scope of mapping is confined to an existing/proposed building area. These
drawings are used as a base for subsequent as-built drawings of facilities and utility
layout maps, i.e., Amenity Mapping / Facility Management (AM/FM) databases.
2.3 As-Built Surveys and Amenity Mapping (AM)/Facility Management

Contour Lines

Topographic maps have contour lines that show how the elevation of the landscape changes. Contour lines are imaginary lines on Earth's surface that connect points that are the same height above sea level. On this map, the contour lines look like concentric circles. The outside line is at sea level, which means it has an elevation of zero meters above sea level. The next contour line has an elevation of 10 meters above sea level. The line above that has an elevation of 20 meters above sea level. Contour lines connect points that share the same elevation: Where they are close together (they never intersect), elevation is changing rapidly in short distance and the terrain is steep. Where contour lines are wide apart, elevation is changing slowly, indicating a gentle slope. In this example, the contour lines are evenly spaced apart. This indicates that the slope of the hill is an even and steady curve of elevation from top to bottom.

Topographical map showing contour lines and contour intervals

Contour Interval

A contour interval is the difference in elevation between any two adjacent contour lines. In this case, the contour interval is 10 meters. Note how the contour lines at 0 and 50 meters are thicker than the rest of the lines. These are known as index contour lines. Index contour lines are usually identified every fourth or fifth line on a topographic map. Index contour lines make it easier to read elevation levels, much like chapters in a book.

What Is A Topographic Map Used For

Topographic maps are very useful for hikers, skiers, and others seeking outdoor recreation. They are also essential tools of the trade for geologists, surveyors, engineers, construction workers, landscape planners, architects, biologists, and many other professions, especially people in the military. Armies throughout history have used information on elevation, hills, water, and other landforms when planning their military strategy. They are also used by the government and industry to assist with urban planning, mining, emergency management, and the establishment of legal boundaries and land ownership. In agriculture, topography maps are used to determine how soil can be conserved and how water will flow over the land. They can help scientists to determine how water and wind may cause erosion and establish conservation areas such as watersheds and wind blocks.

Topographic Map Example

Topographical map of a region

6.What are the different types of girders that can be used in a metro viaduct construction? Explain the differences of the girders and elucidate how a designer has to choose his girder type whilst designing.