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The correct ANSWER is (a) TOTAL rate of microbial growth,

The BEST I can explain: Biomass Growth Rate

The most widely USED expression for the growth rate of micro organisms is given by Monod:

Total rate of microbial growth,

where,

mm = maximum specific growth rate

X = micro organism CONCENTRATION

S = substrate concentration

Ks = substrate concentration at one half the maximum growth rate

Similarly, rate of substrate utilization,

dS = k X S

dtKs+ S

where,

k = maximum specific substrate utilization rate.

Right choice is (a) True

To explain I would say: However, the size and LOCATION of CRACKS can be limited and controlled by appropriate reinforcement, control joints, CURING methodology and concrete mix design. Cracking can ALLOW moisture to penetrate and corrode the reinforcement. This is a serviceability failure in limit state design. Cracking is normally the result of an inadequate quantity of rebar, or rebar spaced at too great a distance. The concrete then cracks either under excess loading, or due to internal effects such as early thermal shrinkage while it cures.

Ultimate failure leading to collapse can be caused by crushing the concrete, which OCCURS when compressive stresses exceed its strength, by yielding or failure of the rebar when bending or shear stresses exceed the strength of the reinforcement, or by bond failure between the concrete and the rebar.

The correct option is (b) 1/30th of span

The explanation: Design CODES prescribe beam width limitations to minimise the shear lag effect on the formation of full-width plastic hinges and achieving the EXPECTED capacity. However, owing to insufficient experimental and analytical studies, empirical design formulas for the beam width limitation, with remarkably different results, have been implemented in different design codes. In this PAPER, parametric studies of the influence of key parameters on the behaviour of wide beam–column connections are conducted BASED on available test results. An effective beam-width MODEL is analytically developed using the equivalent-frame representation, where the effects of torsion of transverse beams and flexure around the joint core are considered. The validity of the model is verified using flexural strengths of test specimens, covering a wide range of design parameters.

Right option is (d) foundation soil and subgrade

Easiest EXPLANATION: A foundation (or, more commonly, base) is the element of an architectural structure which connects it to the ground, and transfers loads from the structure to the ground. FOUNDATIONS are generally considered either SHALLOW or deep. Foundation ENGINEERING is the application of soil mechanics and rock mechanics (Geotechnical engineering) in the design of foundation elements of STRUCTURES.

Right option is (c) valuation

For explanation: By valuation the present value of a property is determined. The present value of property MAY be decided by its SELLING price, or INCOME or rent it may fetch. The value of property depends on its structure, life, MAINTENANCE, location, bank interest, LEGAL control, etc. The value also depends on supply on demand and the purpose for which valuation is required.

Correct answer is (B) 4%

For explanation: If tensile reinforcement of beam should EXCEED 4% of total gross area then some CRACK will be developed in concrete.

Right choice is (a) True

The EXPLANATION is: Construction differs from manufacturing in that manufacturing typically involves mass production of SIMILAR items without a designated purchaser, while construction typically takes place on location for a known CLIENT. Construction as an industry comprises six to nine percent of the gross domestic PRODUCT of developed countries. Construction starts with planning, design, and financing; and continues until the project is built and ready for use.

Correct answer is (d) Rs.12500.00

Explanation: For Rs.5.00 INTEREST, CAPITAL Rs.1000.00

To get Rs.1000.00 interest, capital = (100/5)*1000

= Rs.20000.00

In short capitalized value is – Net annual INCOME*Year’s purchase

For the same net income if the rate of interest is 8% the capitalized value = 1000*(100/8)= Rs.12500.00.

Right answer is (c) Capital Recovery Factor

Best EXPLANATION: The FIRST cost of a capital improvement is converted into equivalent annual cost which is called capital recovery factor. It is the ratio of a constant annuity to the present value of receiving that annuity for a given LENGTH of time.

 This is related to the annuity formula, which GIVES the present value in terms of the annuity, the interest rate, and the number of ANNUITIES.

Correct CHOICE is (d) Ca=H+T+M-Cr

To ELABORATE: The average cost of the annual road system is the SUM of all costs LIKE average cost of highway administration, operation and MAINTENANCE and also the recovery fund.

The correct answer is (a) True

To explain I WOULD say: Wastewater Quantity Estimation – The flow of sanitary sewage ALONE in the absence of storms in dry season is known as dry weather flow (DWF).

Sanitary sewage is mostly the spent WATER of the community draining into the sewer system. It has been observed that a small portion of spent water is lost in evaporation, seepage in GROUND, leakage, etc. Usually 80% of the water supply may be expected to REACH the sewers.

The correct answer is (B) RATE of return method

To elaborate: The TRANSPORT laboratory of LONDON has DEVELOPED this method in which a rate of return is obtained by these parameters, the remaining methods don’t require these parameters.

Right option is (d) Surface drains

The explanation is: These are usually provided at the side of the road and along the boundary line of the building. As far as possible drains should not be laid under the buildings. For EFFICIENT draining the surfacedrains should have certain qualities, such as should be laid in such a gradient to develop self -cleaning velocity, should have a reasonable FREE board at the top, joint should be SMOOTH finished, easy CURVES, INNER surface should be smooth, cheap in construction and maintenance.

Right answer is (a) 326.18 g/d/m^3

The explanation is: Assume 30% of BOD load removed in primary sedimentation i.e., = 210 X 0.30 = 63 mg/l. Remaining BOD = 210 – 63 = 147 mg/l.

Percent of BOD REMOVAL required = (147-30) x 100/147 = 80%

BOD load applied to the FILTER = flow x conc. of sewage (kg/d) = 6 x 106 x 147/106 = 882 kg/d

To find out filter volume, using NRC equation

Depth of filter = 1.5 m, Fiter area = 2704/1.5 = 1802.66 m^2, and Diameter = 48 m < 60 m

Hydraulic loading rate = 6 x 106/103 x 1/1802.66 = 3.33m3/d/m2 < 4 hence o.k.

Organic loading rate = 882 x 1000 / 2704 = 326.18 g/d/m^3 which is approx. equal to 320.

Correct answer is (c) risers MINUS one

Explanation: It is often not simply the sum of the individual tread lengths due to the nosing overlapping between TREADS. If there are N steps, the total RUN equals N-1 times the going: the tread of the last STEP is PART of a landing and is not counted.

Correct choice is (d) increase of speed

For explanation I would say: As there is an increase in the UNEVENNESS index, there is no substantial increase in speed, instead it decreases.

Unevenness index is a measure of unevenness which is the cumulative measure of vertical undulations of the PAVEMENT surface recorded PER unit horizontal length of the road. An unevenness index value less than 1500 mm/km is considered as good, a value less than 2500 mm.km is satisfactory up to speed of 100 kmph and values greater than 3200 mm/km is considered as uncomfortable even for 55 kmph.

Right option is (b) False

The best I can explain: An annuity is a series of payments made at equal intervals. Examples of ANNUITIES are regular deposits to a savings account, MONTHLY home mortgage payments, monthly insurance payments and PENSION payments. Annuities can be classified by the frequency of payment dates. The payments (deposits) may be made weekly, monthly, QUARTERLY, yearly, or at any other regular interval of time.

An annuity which provides for payments for the remainder of a person’s lifetime is a life annuity.

Correct answer is (C) 24,000 l/d/m^2

Easy explanation: Raw water flow per day is 2.4 x 106 l. Detention period is 3h.

Volume of TANK = Flow x Detention period = 2.4 x 103 x 3/24 = 300 m^3

Assume depth of tank = 3.0 m.

SURFACE area = 300/3 = 100 m^2

L/B = 3 (assumed). L = 3B.

3B2 = 100 m^2 i.e. B = 5.8 m

L = 3B = 5.8 X 3 = 17.4 m

Hence surface loading (Overflow rate) = 2.4 x 106 = 24,000 l/d/m^2 < 40,000 l/d/m^2.

Right answer is (b) False

Easy explanation: Stone dust is like a DARKER, coarser version of sand. It is a byproduct of running stones through a crushing machine to make crushed stone. Its EXACT composition will obviously DEPEND on what kind of stone was run through the machine. For instance, sometimes granite is run through such a machine; in other cases, it could be limestone, for EXAMPLE. The machine has a screen that traps the larger material (that is, the crushed stone). The smaller material or “screenings” falls through the screen. Depending on the size of the holes in the screen USED, it can be so fine in texture that it is basically a powder.

Right choice is (a) False

For explanation I would SAY: Also this canal is said to be designed with the balancing depth. Quantity of DIGGING = Quantity in banking i.e. Sectional AREA of digging = Sectional area of two banks or, Bd+sd2 = (b1+b2)*h+2S1 h2. Although it is never possible to adjust the canal section to this requirement but it MAY be quite possible in certain portions.

If the quantity of earthwork in the excavation is more than the quantity of earthwork in banking then the surplus earth is thrown away to form spoil bank.

If the quantity of earthwork in the excavation is less than that of banking then the extra earth is taken from borrow pots in the temporary land WHOSE area is calculated for temporary land acquisition.

The correct CHOICE is (d) MSA

To elaborate: The flexible pavements are designed as per IRC 37 which uses MSA to specify the unit of the vehicles.

MSA is defined as an experimental and MATHEMATICAL method of determining the amount of variation that exists within a measurement process. Variation in the measurement process can directly contribute to our overall process VARIABILITY. MSA is used to certify the measurement system for use by evaluating the system’s ACCURACY, precision and STABILITY.

Correct answer is (a) 30

To explain: The design period of cement roads is usually taken as 30 years but they can even LAST longer if properly MAINTAINED and DESIGNED.

Right option is (c) 15

To explain: The design life of flexible pavement is considered as 15 years, it may last even further if properly maintained.

The wheel load ACTING on the pavement will be distributed to a WIDER area, and the stress decreases with the depth. Taking advantage of this stress distribution characteristic, flexible pavements normally has many layers. Hence, the design of flexible pavement uses the concept of LAYERED system.

The correct ANSWER is (a) True

The explanation: There are, in general, four different types of pipe networks; any one of which either singly or in combinations, can be used for a particular PLACE. They are: Dead END System, Grid IRON System, Ring System and RADIAL System.

Right choice is (c) Quantity Surveyor

Easiest explanation: SERVICES provided by a quantity surveyor may include:

• Cost consulting, cost estimating

• Cost planning and commercial management throughout the entire life cycle of the project from inception to post-completion

• Value determination

• Risk management and calculation

• Procurement advice and assistance during the TENDERING procedures

• Tender analysis and agreement of the contract sum

• Commercial management and contract administration

• Assistance in dispute resolution

• ASSET capitalisation

• Interim valuations and payment assessment

• Cost management process

• Assessing the additional COSTS of design variations.

Correct CHOICE is (B) tunnels

For explanation I WOULD SAY: A bridge doesn’t necessarily have to bridge over water. A bridge can be used to span over a canyon, or depression, or even over a freeway or roadway.

The CORRECT option is (c) sufficient ENOUGH to RESIST SKID

For explanation I would say: The surface of the pavement should be sufficient enough to resist the skid of vehicles by using FRICTION.

Right answer is (d) 48000/-, 6000/-

To EXPLAIN: Cost of construction= Rs.700000.00

Cost of land @Rs.150.00 per sq m = 100*150 = Rs.150000.00

Net return:

On building @ 6% on the cost of construction = 700000.00 *6/100 = Rs.42000.00

On the land @ 4% on the cost of land = 700000.00 *6/100 =Rs.6000.00

Total net rent per YEAR =Rs.48000.00

Gross rent = Net rent + outgoings = 48000+24000.00 = 72000.00 per annum

Gross rent per month = 72000/12 = 6000.00.

Correct OPTION is (d) monolithic character, moulding any shape and fire-resisting

The best explanation: REINFORCED concrete (RC) is a composite material in which concrete’s relatively low tensile strength and DUCTILITY are counteracted by the inclusion of reinforcement having higher tensile strength or ductility. The reinforcement is usually, though not necessarily, steel reinforcing bars (rebar) and is usually embedded passively in the concrete before the concrete sets. Reinforcing schemes are generally designed to resist tensile stresses in particular regions of the concrete that might cause unacceptable cracking and/or structural FAILURE. Modern reinforced concrete can contain varied reinforcing materials made of steel, polymers or alternate composite material in conjunction with rebar or not. Reinforced concrete may also be permanently stressed (in TENSION), so as to improve the behaviour of the final structure under working loads.

The correct choice is (c) Straight line method

The best I can EXPLAIN: In this method a FIXED AMOUNT of the original cost is deducted EVERY year so that at the end of the utility period only the scrap VALUE is left.

Annual depreciation D = Original cost-scrap value/life in year = C-S/n,

Where C- original cost, S- scrap value, n-life of the property in years and D- annual depreciation. The book value after the number of years, say N years = original cost – N*D.

The correct answer is (b) True

To explain: The degree to which each discipline ACTUALLY leads the design depends heavily on the type of STRUCTURE. MANY STRUCTURES are structurally simple and led by architecture, such as multi-storey office buildings and housing, while other structures, such as tensile structures, shells and gridshells are heavily dependent on their form for their strength, and the engineer may have a more SIGNIFICANT influence on the form, and hence much of the aesthetic, than the architect.

Right option is (a) False

Explanation: Canals are human-made channels for water conveyance, or to service water transport vehicles. In most CASES, the ENGINEERED works will have a series of DAMS and locks that create areas of low speed current flow. These areas are referred to as slack water levels, often just CALLED levels.

An canal is also known as a navigation when it parallels a river and shares part of its waters and drainage basin, and leverages its resources by building dams and locks to INCREASE and lengthen its stretches of slack water levels while staying in its valley.

Correct answer is (a) concrete paver blocks

Explanation: The ICPB uses MOSTLY interlocking concrete paver blocks for the construction of pavements. Block paving also known as brick paving is a commonly used decorative method of creating a pavement or hardstanding. The main benefit of bricks over other materials is that individual bricks can later be lifted up and replaced. This allows for remedial work to be carried out under the surface of the paving without leaving a lasting mark once the paving bricks have been replaced. Typical areas of use would be for driveways, pavement, patios, town centres, precincts and more commonly in road SURFACING. Bricks are typically made of concrete or clay, though other composite materials are also used. Each has its own MEANS of construction. The biggest DIFFERENCE is the WAY they set hard ready for use. A clay brick has to be fired in a kiln to bake the brick hard.

The correct choice is (b) 93.33 sq m.

The explanation is: AVERAGE pay = 400+1000/2 = Rs. 700.00 PER month.

Average monthly rent @ 10% of salary = 700.00/10 = Rs.70.00

Average annual rent 70.0*12 = Rs.840.00.

Capital cost of the building @ 6%interest = 840*100/6 = Rs.14000.00

PLINTH area required @Rs.150.00 per sq m of plinth area = 14000/150 = 93.33 sq m.

Normally the quarter for the assistant engineer should be constructed at the cost of Rs.14000.00 having plinth area of 93.33 sq m.

But due to the increase in the cost of construction, this may be increased by 100% and the capital cost of construction may be fixed as Rs.2800.00 and the APPROXIMATE plinth area of 93.33.

The CORRECT CHOICE is (a) Rs.67003.00

The EXPLANATION: Year’s PURCHASE = 100/6 = 16.67

Capitalized value of the property = Net income * Y.P. = 900*16.67 = Rs.15003.00.

Right choice is (a) 45

For explanation: The CONCRETE pavements are designed to sustain a stress of 45Kg/cm^2 which is the maximum limit.

TEMPERATURE Stresses– DUE to the temperature differential between the top and bottom of the slab, curling stresses (SIMILAR to bending stresses) are induced at the bottom or top of the slab

 Frictional stresses– Due to the contraction of slab due to shrinkage or due to drop in temperature tensile stresses are induced at the middle portion of the slab. Wheel Load Stresses– CC slab is subjected to flexural stresses due to the wheel loads.

Correct answer is (a) 12 mm

Easiest explanation: Minimum diameter of LONGITUDINAL bar in RCC column shall not be less than 12mm (IS456:2000, cl 26.5.3.1 d). Indian standards SPECIFY 12mm as the least diameter of a vertical bar and 5mm as the least diameter of lateral bar or STIRRUP.

Correct answer is (b) False

The best I can explain: The PLASTIC as a material for CANAL lining offers certain characteristic ADVANTAGES like negligible weight, easy for handling, spreading and transport, immune to chemical action and speedy construction. The plastic film is spread on the prepared subgrade of the canal. To anchor the membrane on the banks ‘V trenches are PROVIDED. The film is then COVERED with protective soil cover.

Right choice is (c) sub-main canal

For explanation I would say: Main Canal-Main Canal takes off directly from the upstream side of WEIR head works or dam. Usually no DIRECT cultivation is proposed. Most of the main canals are aligned as contour canals to DERIVE benefit.

Branch Canal-All off takes from main canal with head DISCHARGE of 14-15 cumecs and above are termed as branch canals.

Major Distributary-All off takes from main canal or branch canal with head discharge from 0.028 to 15 cumecs are termed as major distributaries.

Correct option is (c) canal LINING

For explanation I would say: An important REASON for lining a canal can be the reduction in water losses, as water losses in unlined IRRIGATION canals can be high. Canals that carry from 30 to 150 liters/sec can lose 10 to 15% of this flow by seepage and water consumption by weeds. Lining a canal will not completely eliminate these losses, but roughly 60 to 80% of the water that is lost in unlined irrigation canals can be saved by a hard-surface lining. 42 Canal lining Minimizing water losses is very important, and especially so in schemes where irrigation water is pumped. Reduced water losses means LESS water to PUMP and thus a reduction in pumping costs.

Right choice is (d) Intercept type

Best explanation: The simple flow through type equalization tank is mainly useful in assisting SELF neutralization or evening out of fluctuating concentrations, not for balancing of flows since a flow through type tank once filled, gives output equal to input.

Flow balancing and self-neutralization are both achieved by using two tanks, intermittently one after another. One tank is allowed to fill up after which it is checked for pH (or any other parameter) and then allowed to empty out. The second tank goes through a similar ROUTINE. INTERMITTENT flow type tanks are economic for small flows from industries.

When flows are large an equalization tank of such a SIZE may have to be provided that inflow can be variable while outflow is at a CONSTANT rate, generally by a pump.The capacity required is determined from a plot of the cumulative inflow and a plot of the constant rate outflow and measuring the gaps between the two plots. A factor of safety may be applied if desired.

Correct OPTION is (d) Rs.907.20

To elaborate: The total AMOUNT of sinking fund to be ACCUMULATED at the end of 20 years.

S = 30000 * 90/100 = Rs.27000.00

Annual instalment of sinking fund.

I = Si / [(1+i)n-1] = 27000*0.04/(1+0.04)20-1 = 27000*0.0336 = Rs.907.20

Annual Instalment for sinking fund REQUIRED for 20 years = Rs.907.20.

Correct option is (c) culvert

To elaborate: A BRIDGE is a structure built to span physical obstacles without CLOSING the way underneath such as a body of water, valley, or road, for the PURPOSE of providing PASSAGE over the obstacle. There are many different DESIGNS that each serve a particular purpose and apply to different situations.

Correct choice is (b) Rs.125

The explanation is: The annual sinking FUND, I = Si / [(1+i)n-1] = 2500*0.04/(1+0.04)15-1 = 2500*0.05 = Rs.125

The OWNER is to deposit Rs.125/- annually in 4% compound interest carrying investment for 15 YEARS to accumulate Rs.2500/-.

Correct answer is (a) True

Best explanation: There are many routes to the different careers WITHIN the construction industry. These three main tiers are based on EDUCATIONAL background and training, which vary by country:

• Unskilled and semi-skilled – General site LABOR with little or no construction qualifications.

• Skilled – Tradesmen who’ve served apprenticeships, TYPICALLY in labor unions, and on-site managers who possess extensive knowledge and experience in their craft or profession.

• Technical and management – Personnel with the greatest educational qualifications, usually graduate degrees, trained to design, manage and instruct the construction process.