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Q.1 Write in brief about general classification of surveys. [5]

A. Primary Divisions of Surveying

Based upon the requirements and magnitude of the survey, the survey has been classified broadly into two main categories : 

1. PLANE SURVEYING: In this type of surveying, the mean surface of the earth is considered as a plane, and the spheroidal shape is neglected. All triangles formed by survey lines are considered as plane triangles. The level line is taken as straight, and all plumb lines are considered to be parallel. Plane surveying is done for smaller areas in consideration. If a large area is considered, the discrepancy will become apparent between the area of the horizontal plane and the actual curved area of the earth’s surface.

2. GEODETIC SURVEYING: This is a type of surveying in which the shape of the earth is taken into account. All lines are taken as curved lines and triangles as spherical triangles. Geodetic survey includes work of larger magnitude and high degree of accuracy. The purpose of geodetic survey is to determine the precise position on the surface of earth, of a system of widely distant points which form control stations to which surveys of less precision may be referred. Geodetic surveys are employed for an area larger than 195 (km^2). 

B. Secondary Divisions of Surveying

1. BASED ON NATURE OF SURVEY

• Land Survey: It is the survey being carried out on land. It involves running survey lines and determining their length and directions, thereby subdividing the area into definite shapes and sizes and calculating their areas as well in order to set up a structure.
• Marine or Hydrographic Survey: It involves a survey of water bodies like streams, seas, ponds, etc. the basic purpose of this survey is to establish shorelines. This survey is also done to determine the amount of water stored by a water body, water supply, navigation possibilities etc. 
• Underground Survey: Underground surveys are done to construct tunnels for railways, highways, water supply, mines, etc. 
• Aerial Survey: This survey is carried out above ground by taking aerial photographs with cameras fitted to aeroplanes, helicopters etc. This survey is particularly required for preparing large-scale maps of an area and for the development of projects in areas which are practically inaccessible or too time-consuming.

2. BASED ON THE OBJECT OF SURVEYING

• Engineering Survey: This survey is required to be done for acquiring information for the planning and design of engineering projects like highways, railways, dams, reservoirs, water supply etc. 
• Military Survey: This method of survey is employed for determining points of strategic importance. 
• Mine Survey: To explore mineral wealth of an area, a mine survey is done. 
• Geological Survey: This type of survey is used to determine various layers of strata in earth crust. 
• Archaeological Survey: It is a type of field research to find out location, distribution and organization of past human cultures and civilizations. 

3. BASED ON INSTRUMENT USED  

• Chain Survey: In chain survey, only linear measurements are made with chain or tape, and no angular measurements are made. This survey is of limited use since it requires clear ground without any obstructions like trees, buildings, rivers etc. This survey is particularly useful for constructing roads, sewer lines, water supply lines, etc. 
• Traverse Survey : In a traverse survey, both linear and angular measurements are made. Linear measurements are done using chain or tape and angular measurements are done using compass. This type of survey is done for large areas like dams and reservoirs. 
• Triangulation Survey: This method is also used for larger areas. The entire area is divided into a network of triangles, and any one side of the triangle is measured with very high precision. This line is termed as a baseline. All the angles of the network are measured. The lengths of the sides of the triangle are then computed using the laws of triangles.
• Tacheometric Survey: In this survey, both horizontal and vertical distances are measured by sighting a graduated staff with a transit telescope fitted with an anallactic lens. It is particularly useful when direct measurements on a horizontal plane are impossible. 
• Plane Table Survey: Observations and plotting are done simultaneously in plane table surveys. The advantage of this method is that there is less possibility of omitting any important measurement, since the actual field being surveyed is in view of the plot in the field itself. 
• Total Station Survey: Total station is the combination of conventional transit theodolite with an EDM (Electronic Distance Meter) instrument. It reads and records the horizontal and vertical distances together with slope distances. The data of the total station survey can be fed into the computer very easily and instantaneously, making it error-free and less time-consuming. 
• Satellite Survey: In this method of survey, information about the land or space is determined using satellite-based navigation systems like the GPS (Global Positioning System). 

Q.2 What do you mean by paint and varnishes? What is the purpose of using it? [3+2]

PAINT AND USES

A Paint is a Solution or suspension (emulsion) of pigment, binder, and mineral solvent (or water) that on drying forms an adhering film on the surface it is applied for protection and/or decoration. Paint is considered as a decorative element that provides protection to surface. Applied over metals, wood, plaster, concrete etc. For different surfaces different types of paints from different companies are used.

Uses of paints

Q.3 Describe shortly classification of different bricks. [5]

A. FIRST CLASS BRICK

• These are well-burnt bricks, and all the corners are perfect.
• They produced metallic sound when struck to each other.
• All the faces and surface are smooth.
• Compressive strength is more than 10.5-14 MPa or N/mm2
• These are suitable for building walls where plaster is not required.

B. SECOND CLASS BRICK

• These are also well burnt bricks, and these have also smoot surface. But the shape may quite undulate.
• They also produced metallic sound when struck to each other.
• Compressive strength is about 7-10.5 MPa or N/mm2
• The shape may quite undulate.
• These are used in building works where plaster is needed.

C. THIRD CLASS BRICK

• These are not uniformly burnt.
• These bricks have non-uniform shape and size.
• They don’t produce metallic sound when struck each other.
• Compressive strength is about 3.5-7 MPa or N/mm2
• These are used in general works in foundation and non-important structures.

D. JHAMAS/ FOURTH CLASS BRICK

• They are over burnt and dark in color.
• They produced metallic sound when struck to each other.
• They have higher compressive strength than first class bricks.
• Their shape is deformed, and surface is not smooth.
• They are used in unimportant location and don’t use in super structure due to uneven shape and sizes.

Q.4 Differentiate between Shear Force and Bending Moment. Calculate the maximum bending moment of simply supported beam of span (L) having uniformly distributed load (w) per unit length. [3+2]

Differentiate between Shear Force and Bending Moment

Shear force	Bending moment
Shear force is maximum at support and zero at centre.	Bending moment maximum at centre and zero at support for all simply supported beams.
Shear force acts on a place and it induce on a direct place where the loads are transferred.	Bending moment act with reference to lever arm distance., (B.M = force X Distance)
unit for shear force is KN	unit for mending moment is KN.m

Q.5 Define levelling. Explain the temporary adjustment of levelling. [5]

Leveling

Levelling is a branch of surveying in civil engineering to measure levels of different points with respect to a fixed point such as elevation of a building, height of one point from ground etc.

Temporary adjustment of levelling

The adjustments to be made at every setting of the instrument are called temporary adjustments. The following three adjustments are required for the instrument whenever set over a new point before taking a reading:

1. SETTING
2. LEVELLING
3. FOCUSSING

1. SETTING: Tripod stand is set on the ground firmly so that its top is at a convenient height. Then the level is fixed on its top. By turning tripod legs radially or circumferentially, the instrument is approximately levelled. Some instruments are provided with a less sensitive circular bubble on tribrach for this purpose.

2. LEVELLING: The procedure of accurate levelling with three levelling screw is as given below:
(i) Loosen the clamp and turn the telescope until the bubble axis is parallel to the line joining any two screws [Ref. Fig. 15.5 (a)].

(ii) Turn the two screws inward or outward equally and simultaneously till bubble is centred.
(iii) Turn the telescope by 90° so that it lies over the third screw [Fig. 15.4 (b)] and level the instrument by operating the third screw.
(iv) Turn back the telescope to its original position [Fig. 15.5 (a)] and check the bubble. Repeat steps (ii) to (iv) till bubble is centred for both positions of the telescope.
(v) Rotate the instrument by 180°. Check the levelling.

3. FOCUSSING: Focussing is necessary to eliminate parallax while taking reading on the staff. The following two steps are required in focussing:
(i) Focussing the eyepiece: For this, hold a sheet of white paper in front of telescope and rotate eyepiece in or out till the cross hairs are seen sharp and distinct.
(ii) Focussing the objective: For this telescope is directed towards the staff and the focussing screw is turned till the reading appears clear and sharp.

Q.6 Differentiate between one-way slab and two-way slab. What are the design procedure for slab? [2+3]

One Way Slab	Two Way Slab
In one way slab, the ratio of longer span panel (L) to shorter span panel (B) is equal or greater than 2. Thus, L/B ≥ 2	In two way slab, the ratio of longer span panel (L) to shorter span panel (B) is less than 2. Thus, L/B < 2.
Slab panel is supported on two opposite sides in short direction of one-way slab	Slab panel is supported on four sides of two-way slab.
One way slab bends or deflect in a direction perpendicular to the supporting edges	Two way slab bend or deflect in both directions.
Deflected shape of one way slab is cylindrical.	Deflected shape of two way slab is dish-shaped.
one way slab has structural strength in shortest direction	Two way slab has structural strength in the shortest direction
Main reinforcement is provided in only one direction for one way slabs.	Main reinforcement is provided in both the direction for two way slabs.

Q.7 What happens if soil is not compacted? How does compaction affect engineering properties of soils? [5+5]

Soil compaction is the process of increasing the density of soil by reducing air voids, typically by applying mechanical pressure. If soil is not compacted properly, several negative consequences can occur, affecting both the immediate and long-term stability of structures built on it. Here are the key issues:

1. REDUCED LOAD-BEARING CAPACITY: Uncompacted soil has a lower density, leading to poor load-bearing capacity. This means that structures, such as buildings, roads, and pavements, may settle unevenly or experience excessive settlement under load, potentially leading to structural damage.
2. INCREASED SETTLEMENT: When soil is not compacted, the voids between soil particles remain larger, allowing more air or water to occupy those spaces. Over time, under load, the soil particles may rearrange, causing excessive and unpredictable settlement.
3. WATER DRAINAGE PROBLEMS: Compaction helps reduce the permeability of soil by decreasing the voids. If the soil is not compacted, it can result in excessive water retention, leading to waterlogging. In cases of high clay content, water may not drain properly, causing foundation instability and weakening of the structure.
4. REDUCED SOIL STRENGTH: Soil strength (shear strength) is significantly affected by compaction. Uncompacted soil may not resist shear stresses effectively, leading to instability, especially in areas prone to earthquakes or heavy loads.
5. POOR SOIL STRUCTURE: The proper compaction of soil ensures a stable particle arrangement that improves soil structure. Without compaction, soils may remain loosely packed, leading to erosion, instability, and difficulty in handling the materials during construction activities.

Effects of Compaction on Soil Properties

Q.8 What is the different between pipe flow and open channel flow, discuss in detail with example? [10]

Open channel flow	Pipe flow
Open Channel Flow is a type of fluid flow in a conduit with a free surface open to the atmosphere.	The pipe flow is a type of flow within a closed conduit.
Open Channel Flow has a free surface	There is no Free surface in pipe flow
The pressure at the free surface remains constant	Pressure in the pipe is not constant
Flow Driven by Gravity	Flow Driven by Pressure
The maximum velocity occurs at a little distance below the water surface	The maximum velocity occurs at the center of the pipe.
Surface roughness varies with depth of flow	Surface roughness varies with the type of pipe material
HGL (Hydraulic Gradient Line) coincides with the water surface line.	HGL (Hydraulic Gradient Line) do not coincide top surface of the water
The Cross-section of an open channel can be trapezoidal, triangular, rectangular, circular, etc.	The Cross-section of a pipe generally circular.

Q.9 Differentiate between shallow foundation and deep foundation. [5]

Shallow foundations	Deep foundations
The foundation which are placed near the surface of earth are called shallow foundations.	The foundation which are placed at a greater depth are called deep foundations.
The depth of shallow foundation is less than the width of footing.	The deep foundation is greater than the width they footing.
Shallow foundation are cheaper.	Deep foundation are expensive.
Shallow foundation is easier to construct.	Deep foundation is complex to construct.
Shallow foundation mostly transfer load by end bearing.	Deep foundation transfer load by skin friction and bearing.
Less time is required to construct.	More time is required to construct.
They are provided when bearing capacity of soil is adequate at less depth.	These are provided where bearing capacity of soil is very less.
These are provided where ground water table is low.	These are provided when ground water table are high.

Q.10 Write short note on Duty, Delta, Base period in Irrigation System. [5]

Duty:

The term duty means the area of land that can be irrigated with unit volume of irrigation water. Duty represents the irrigating capacity of a unit. It is the relation the between the area of a crop irrigated and the quantity of irrigation water required during the entire period of the growth of that crop. For example, if 3 cumecs of water supply is required for a crop sown in an area of 5100 hectares, the duty of irrigation water will be 5100/3 = 1700 hectares/cumecs, and the discharge of 3 cumecs will be required throughout the base period.

Delta:

It is the total depth of the water required by a crop during the entire period the crop is in the field and is denoted by the symbol ∆. For example, if a crop requires about 12 watering at an interval of 10 days, and a water depth of 10 cm. If the area under the crop is A hectares, the total quantity will be 1.20 X A = 1.2 A hectare-metres in a period of 120 days.

Base Period:

Base Period for a crop refers to the whole period of cultivation from the time when irrigation water is first issued for preparation of the ground for planting the crop, to its last watering before harvesting.

Relation between Duty and Delta

D= duty in hectares/cumec

∆= total depth of water supplied in metres

B= base period in days

i. If we take a field of area D hectares, water supplied to the field corresponding to the water depth ∆ metres will be = ∆ x D hectares-metres = D x ∆ x1044 cubic-metres. …. (1)

ii. Again for the same field of D hectares, one cumec of water is required to flow during the entire base period. Hence, water supplied to this field. = (1) x (B x 24 x 60 x 60) m33 …. (2)

Equating Equations (1) and (2), we get D x ∆ x 1044 = B x 24 x 60 x 60

∆ = B×24×60×60D×104=8.64 B/D metres.B×24×60×60D×104=8.64 B/D metres.

1 hectare = 104 sq metres

cumec-day = 8.64 hectare-metres

Q.11 How do you provide longitudinal and cross drainages in hill roads? Explain. [5]

Longitudinal Drainage in Hill Roads

Longitudinal drainage refers to the drainage system that runs parallel to the road alignment, designed to remove water that collects along the road’s surface due to rainfall or runoff. In hill roads, where terrain and weather conditions can cause water accumulation, longitudinal drainage plays a vital role in maintaining the stability of the road and preventing erosion or landslides.

Key Features and Methods for Longitudinal Drainage in Hill Roads:

1. CAMBER OR CROSS SLOPE: Hill roads are constructed with a camber or transverse slope to allow water to flow from the center of the road to the sides. This slope ensures that surface water is directed toward the shoulders or side drains instead of accumulating on the road surface.
2. SIDE DRAINS OR SHOULDER DRAINS:
   • Side Drains: These are ditches or channels constructed along the road edge to carry away surface water. They should be designed with adequate depth and width to handle the volume of water expected. In hilly areas, side drains are often built on the higher side of the road to collect and direct runoff.
   • Shoulder Drains: These are smaller drains provided along the shoulder of the road, particularly on steep terrains, to collect and carry away water from the road surface into natural or man-made outlets.
3. DRAINAGE CULVERTS: Culverts are used to direct water under the road. They are especially important in hilly areas where the road crosses small streams, ravines, or areas prone to flash floods. The culverts should be designed to handle large water volumes, particularly during the rainy season.
4. MAINTENANCE OF WATER FLOW: Regular cleaning and maintenance of the longitudinal drainage system are essential to ensure water can flow freely. Blocked drains or culverts can lead to water pooling, which can cause road surface damage or even road failure.

Cross Drainage in Hill Roads

Cross drainage refers to the system designed to remove water that flows perpendicular to the road alignment, usually due to the natural flow of rivers, streams, or surface runoff from the surrounding hillsides. Effective cross drainage is critical in hilly regions to prevent water from undermining the road structure and to avoid erosion or landslides.

Key Features and Methods for Cross Drainage in Hill Roads:

1. CROSS CULVERTS AND BRIDGES:
   • Cross Culverts: These are structures that allow the flow of water across the road, preventing the road from being washed away by water. In hilly areas, these culverts must be sized appropriately to handle floodwaters. Proper installation and maintenance of cross culverts are essential to avoid the formation of water pockets and road damage.
   • Bridges: In areas where water flow is more substantial (e.g., across rivers or large streams), bridges may be required. These need to be designed to withstand the forces of water and be built to ensure minimal disruption to the road alignment.
2. SCOUR PROTECTION: In areas where cross drainage structures like culverts or bridges are present, measures like stone pitching, gabions, or retaining walls are used to prevent scour (erosion) around the structures. This is especially important in hilly areas where heavy rainfall and fast-moving water can erode the foundation of drainage structures.
3. STORMWATER DRAINS: These drains, placed perpendicular to the road alignment, collect water from the surrounding hillsides and direct it to the nearest cross drainage points like culverts or natural outlets. These drains help manage water that flows downhill during periods of heavy rainfall, preventing it from accumulating on or near the road.
4. SLOPE STABILIZATION: In hilly regions, controlling water runoff is critical for slope stabilization. Techniques like terracing, planting grass or shrubs, and using retaining walls can be employed to manage cross drainage effectively and prevent landslides or erosion that could disrupt the road.

Q.12 Why estimate should be prepared? What are the purposes of rate analysis and which points are taken into consideration while preparing analysis of rate? [2+3]

Why Estimate Should Be Prepared?

An estimate is prepared to predict the cost, time, and resources required for the construction of a project. It is an essential part of the planning and execution phases in construction and serves multiple purposes:

1. Budgeting and Cost Control: An estimate provides a clear picture of the overall project cost, which helps the owner and project managers allocate financial resources effectively and control spending.
2. Planning: It helps in the planning phase by setting expectations for material, labor, and equipment requirements, ensuring the project stays on track and within budget.
3. Tendering: Accurate estimates are crucial for contractors to submit competitive and realistic bids during the tendering process. It also helps in determining the cost of the project for future project negotiations.
4. Approval and Funding: Estimates are used to seek financial approval from owners or authorities for funding the project. It provides a cost breakdown to justify the expenditure.
5. Decision Making: They help in making informed decisions regarding the feasibility of the project, considering both time and cost constraints.

Purposes of Rate Analysis

Rate analysis helps in determining the cost per unit of a specific activity or material required for a construction project. The primary purposes of rate analysis include:

1. Cost Estimation: It assists in calculating the total cost of construction work based on the rates of labor, materials, and equipment used.
2. Pricing for Tendering: Helps contractors prepare accurate tender bids by providing a breakdown of the costs associated with each item of work.
3. Budgeting: Enables the preparation of detailed cost breakdowns, helping owners and project managers maintain budget control throughout the project.
4. Cost Control: It allows for comparing actual costs with estimated costs, helping identify discrepancies and areas where cost reductions may be made.
5. Quality Control: Rate analysis ensures that the materials, labor, and methods used are consistent with the quality requirements of the project.

Points to Consider in Rate Analysis

When preparing a rate analysis, the following points are considered:

1. Labor Costs: This includes the wages of workers required for specific tasks. The time needed to complete each task is estimated, and the rate of wages is applied.
2. Material Costs: The cost of materials required for the activity, including transportation, taxes, and wastage. Material prices are generally taken from the local market rates or supplier quotations.
3. Overheads: These are indirect costs such as site management, temporary facilities, insurance, and other administrative costs.
4. Equipment and Machinery: The cost of machinery and tools required for the work, including renting or operating costs and maintenance expenses.
5. Profit Margin: A certain percentage is added for profit based on the overall cost incurred for the work.
6. Contingencies: It accounts for unforeseen expenses, such as price fluctuations in materials, labor strikes, or weather delays.
7. Productivity: The efficiency and productivity of workers and machines. This helps in estimating how much work can be done in a given time frame.
8. Time Factor: The time required to complete the task, which influences labor and equipment costs. The longer the duration, the higher the associated costs.

Q.13 What is the role of civil sub-engineer in establishing good relation among owner, consultant and contractor? [5]

Role of a Civil Sub-Engineer in Establishing Good Relations Among Owner, Consultant, and Contractor

The role of a Civil Sub-Engineer in establishing good relationships among the owner, consultant, and contractor is essential to ensure the smooth execution of a construction project. As a key intermediary, the Civil Sub-Engineer helps maintain clear communication, resolve conflicts, and ensure that all parties work collaboratively towards achieving the project goals. Below are the key roles the Civil Sub-Engineer plays in this process:

1. Facilitating Communication: A Civil Sub-Engineer ensures effective communication between the owner, consultant, and contractor. They relay important information, such as project updates, issues, and concerns, ensuring all parties are aligned. By serving as a communication bridge, they help prevent misunderstandings and ensure that everyone involved is well-informed about the progress, requirements, and expectations.

2. Mediating Conflicts: Conflicts are inevitable in any construction project due to differing perspectives or challenges faced by the parties involved. The Civil Sub-Engineer plays a critical role in mediating conflicts by understanding the concerns of the owner, consultant, and contractor and working towards a resolution. By addressing issues promptly and diplomatically, they help prevent disputes from escalating, ensuring the project progresses smoothly.

3. Monitoring Project Progress and Quality: The Civil Sub-Engineer is responsible for monitoring the progress and quality of the work on-site. By ensuring that the contractor is adhering to the specifications provided by the consultant and meeting the owner’s expectations, they act as a quality control mechanism. This proactive approach helps build trust among the owner, consultant, and contractor, as it demonstrates that the project is on track and meets the required standards.

4. Ensuring Adherence to Contractual Obligations: The Civil Sub-Engineer helps ensure that all parties adhere to the terms and conditions outlined in the contract. They ensure that the contractor follows the designs and plans provided by the consultant and that the work is completed within the agreed-upon timeline and budget. This role is vital in maintaining transparency and accountability among all stakeholders.

5. Providing Technical Support and Advice: The Civil Sub-Engineer offers technical support to both the contractor and consultant, ensuring that construction activities are carried out according to the approved designs and industry standards. They assist in resolving any technical challenges and provide advice on practical solutions. This support helps the contractor execute the work efficiently while ensuring that the consultant’s design is correctly implemented.

Q.14 Explain the importance of supervision in construction projects. [5]

Importance of site supervision in construction projects

1. EFFICIENCY AND PRODUCTIVITY: Efficiency and productivity are essential for a project to be completed on time as any delay in construction progress can create a massive direct or indirect cost. Site supervisors are responsible for evaluating the workers’ performances and giving clear instructions so that the workers know exactly what to do in their respective positions.

2. QUALITY CONTROL: Quality control details ensuring adherence to the original design and planning decision, which is part of the work scope of the site supervisors. Well-trained site supervisors guarantee the materials, equipment, and system used are of good quality and conform to the standards. Moreover, continuous monitoring of construction progress and quality of work by site supervisors can ensure that the efforts made by workers meet the desired quality.

3. BUDGET CONTROL: This is to ensure the cost of the project stays within the budget throughout the whole project. Site supervision can help ensure the project’s expenditure is within budget by strictly inspecting the materials and workmanship throughout the construction process. This means that site supervisors should be aware of the prices and cost levels.

4. LEGAL ASPECT: Apart from looking after the safety of the construction site, site supervision also takes care of the legal aspects. Many legal requirements and acts set standards for supervision and clarify what protocol to be followed and what safety processes must be in place. This ensures conformity with the local laws and standards.

5. SAFETY MEASURES: Regardless of the scale of the construction site, there are possibilities for risks and injuries. While prevention is better than cure, site supervision will have to enforce site safety procedures to minimize work-related injuries or accidents. For instance, ensuring everyone at the site is wearing Personal Protective Equipment (PPE) such as a safety helmet, safety boots, high-visibility vest, and gloves for safety purposes.

Q.15 Write different components of gravity water supply system. What are major factors which needs to be considered during design of this system? [10]

Components of a Gravity Water Supply System

A gravity water supply system uses the natural force of gravity to transport water from a source to the point of use, typically without the need for pumps. The primary components of such a system are as follows:

1. SOURCE: The source of water can be a river, stream, lake, reservoir, or groundwater. The location and quality of the water source are crucial for ensuring a reliable and clean supply of water.
2. INTAKE STRUCTURTES: The intake structure is designed to collect water from the source. It typically consists of a screened structure to filter debris and sediment from entering the system, ensuring clean water is conveyed.
3. CONDUITS (PIPES OR CHANNELS): These are used to transport water from the intake to the distribution point. The conduits are generally made of materials like concrete, steel, or PVC and are laid out with a slope to allow water to flow naturally due to gravity.
4. RESERVOIR OR STORAGE TANK: A storage tank or reservoir is used to store water and regulate the flow to ensure a continuous supply. It serves as a buffer to manage water demand fluctuations and ensures a stable supply, particularly during peak usage times.
5. DISTRIBUTION SYSTEM: The distribution network consists of pipes that carry water from the storage tanks to the end users, whether it be homes, industries, or other facilities. These pipes are usually laid underground to protect them from damage and ensure an even water supply.
6. VALVE AND CONTROL STRUCTURES: Valves are used to control the flow of water in the system. These helps isolate sections of the system for maintenance or repairs and regulate the pressure within the pipes.
7. FLOW REGULATION DEVICES: Flow regulators or meters are used to measure and control the flow of water throughout the system, ensuring that the required amount of water is delivered to each point of use.
8. OUTLET STRUCTURES: The outlet structure ensures that the water reaches the end-users effectively. It can include taps, standpipes, or connections to household or industrial plumbing.

Major Factors to Consider During the Design of a Gravity Water Supply System

When designing a gravity water supply system, several factors must be carefully considered to ensure the system is efficient, reliable, and sustainable:

1. TOPOGRAPHY AND ELEVATION: The natural slope of the land plays a significant role in the system’s design. The water source must be located at a higher elevation than the area it serves to allow the natural flow of water. The topography of the region affects the design of the pipeline network and storage reservoirs.
2. WATER DEMAND: Estimating the water demand is crucial for designing the system’s capacity. This includes considering factors like population size, usage per capita, and the requirements of industries or agriculture that may rely on the system.
3. SOURCE OF WATER: The quantity, quality, and reliability of the water source need to be assessed. Factors such as seasonal variation in flow, potential contamination, and availability during dry periods must be considered to ensure a continuous water supply.
4. PIPE SIZING AND LAYOUT: Properly sizing the pipes is essential to maintain efficient flow and pressure. Incorrectly sized pipes can lead to low pressure or over-pressurization, both of which can damage the system or reduce efficiency. The layout should also minimize friction losses and optimize the flow.
5. WATER QUALITY: The quality of the water source is an essential factor. The design must incorporate adequate filtration and treatment facilities if the water source is prone to contamination. The intake structure should also be designed to prevent debris from entering the system.
6. COST AND BUDGET: The overall cost of the water supply system, including construction, operation, and maintenance, must be evaluated. The design should balance efficiency and practicality, considering the available budget and funding options.
7. MATERIALS FOR CONSTRUCTION: The choice of materials for pipes, tanks, and structures should be durable, cost-effective, and suitable for local conditions. Common materials include concrete, steel, and PVC for pipes, and reinforced concrete for tanks.
8. ENVIRONMENTAL IMPACT: The environmental impact of the system, including its effect on local ecosystems, water quality, and surrounding communities, must be carefully assessed. Minimizing disruption to the environment and ensuring sustainability are key factors in the design process.
9. MAINTENANCE AND OPERATION: The system design should allow for easy maintenance and repair. This includes ensuring access to key components, such as valves, reservoirs, and pipelines, and creating a monitoring system to detect issues early.
10. RESILIENCE TO NATURAL DISASTERS: The system should be designed to withstand natural disasters such as floods, earthquakes, or droughts. This includes placing critical infrastructure above flood levels, designing flexible pipeline networks, and planning for water storage during periods of low supply.

Q.16 What are the design and construction problems of hill road? What are the special consideration which need to be followed in the selection of alignments for road in mountainous area? [10]

The design and construction problems in hill roads are as follows: –

• A hilly or mountainous area is characterized by highly broken relief with vastly differing elevations and steep slopes, deep gorges etc. which may unnecessarily increase road length.
• The geological condition varies from place to place.
• Hill slopes stable before construction may not be as stable due to increased human activities.
• There may be variation in hydro-geological conditions which may easily be overlooked during design and construction
• Due to highly broken relief construction of special structures should be done at different places. This increases the cost of the construction.
• Variation in the climatic condition such as the change in temperature due to altitude difference, pressure variation, precipitation increases at greater height etc.
• High-speed runoff occurs due to the presence of high cross slopes.
• Filling may overload the weak soil underneath which may trigger new slides.
• The need of design of hairpin bends to attain heights.

In locating the alignment special consideration should be made in respect to the variations in:

1. TEMPERATURE: Air temperature is in the hills is lower than in the valley. The temperature drop being approximately 0.5° per 100 m of rising. On slopes facing south and southwest snow disappears rapidly, and rainwater evaporates quickly while on slopes facing north and northeast rainwater or snow may remain for the longer time. Unequal warming of slopes, sharp temperature variations and erosion by water are the causes of slope facing south and southwest.

2. RAINFALL: Rainfall increases with increase in sea level. The maximum rainfall is in the zone of intensive cloud formation at 1500-2500 m above sea level. Generally, the increase of rainfall for every 100 m of elevation averages 40 to 60 mm. In summer very heavy storms may occur in the hills and about 15 to 25% of the annual may occur in a single rainfall. The effects of these types of rainfall are serious and should be considered well.

3. ATMOSPHERIC PRESSURE AND WINDS: It decreases with increase in elevation. At high altitudes, the wind velocities may reach up to 25-30 m/s and depth of frost penetration is also 1.5 to 2 m. Intensive weathering of rocks because of sharp temperature variations which cause high winds.

4. GEOLOGICAL CONDITIONS: The inclination of folds may vary from horizontal to vertical stratification of rock. These folds often have faults. Limestone or sandstone folds may be interleaved with layers of clay which when wetted may cause fracturing along their surface. This may result in shear or slip fold. The degree of stability of hill slopes depends on types of rock, degree of strata inclination or dip, occurrence of clay seams, the hardness of the rocks and presence of ground water. When locating the route an engineer must study the details of geological conditions of that area and follow stable hill slopes where no ground water, landslides, and unstable folds occur.