A field density test has been run on a soil containing 18% of its weight in particles retained on the No. 4 sieve. The dry density of the total sample was 128.7 pcf and the water content was 7%. The water content of the gravel fraction was 3%. the specific gravity of the solids was 2.69. Compute the water content and dry density of the soil fraction of the fill that passes the No. 4 sieve.

1) Benefits realized on this project by utilizing a mass timber design scheme when compared to the original steel design included:

a. Reduced floor to floor height

b. Longer floor panel/slab spans

c. Easier MEP coordination

d. All of the above

2) Glue-laminated timber was used for which components on the UMass Design Building: (choose all that apply)

a. Only beams

b. Beams and columns

c. Beams, columns and braced frames

d. Only braced frames

3) Cross-Laminated Timber (CLT) can only be used for horizontal surfaces (floors and roofs), not for walls:

a. True

b. False

4) CLT-concrete composite floor systems utilize each material in its most efficient manner to provide: (choose all that apply)

a. Stiffer floor panels capable of longer spans

b. Lower panel mass

c. Quicker installation

d. Easier building code approval

5) The inherent mass and charring characteristics of mass timber sections allow them to be exposed while achieving fire-resistance without the need for coatings or protection layers such as gypsum:

a. True

b. False

6) The timber zipper roof trusses over the lower level lobby provide which building feature:

a. Steep slope roofs for adequate snow shedding

b. An accessible green roof above the open lobby

c. Crane rails utilized in the wood testing labs

d. Seismic load resistance as shear walls

7) The beam to column connections on the UMass Design Building utilized: (choose all that apply)

a. Large exposed steel gusset plate connections with through bolts

b. Traditional timber frame joinery

c. Steel hangers concealed by the timber for fire-resistance purposes

d. Lag screws and knife plates

In an industrial project, a designer wants to use W16x57, F_y = 50 ksi, of various heights, as columns.

All columns will have fixed ends at the top and bottom (K=0.5).

Note that tables for W16 are not available in the Steel Manual, as it is a special use.

Use formulas, for Euler’s buckling stress; and for short and long columns, given in the PowerPoint.

Use radius of gyration, r_y, of 1.60 inches.

Calculate the design strength, F_C P_N, (Kips) of this shape for the 15’, 30’, and 45’ column heights used in that project.

What are three items of concern for stormwater pollution related to general operations on a construction site?

When protecting palletized storage of expanded exposed Group A plastic in a stable array stored up to 25 ft high in a 30 ft building, what is the correct column to use in Table 21.3.3(a) (NFPA 13-2019)? And what is an acceptable density (measured in gpm per sq. ft) for the storage?

Would you like to recommend cohesive soils as the backfills behind a retaining structure? Justify your answer.

Design an individual column footing where DL = 200k, LL = 500k, allowable soil pressure = 3k/ft2, f′c col = 4ksi, f′c ftg = 3ksi, 28″ x 28″ column, supporting interior column.

The city of Stay at Home counted 150,000 people in the 1970s, when its wastewater treatment plant was built. Because of a recent economic boom, the city has been growing at a fast rate and new developments will bring the total population to 350,000 people within 10 years from now. There is no more footprint available to expand the existing plant, which is land locked in the middle of an industrial zone. The city council, therefore, decided to build a new plant on the other side of the town. This new plant will be designed to treat the wastewater from the additional 200,000 people. You are the designer. Analysis of the last 5 years of operating data shows that the old plant received an average volume of 15 million gallon per day (MGD) with an average BOD5 concentration of 250 mgBOD5/L and an average TSS concentration of 270 mgTSS/L. This average BOD5 and TSS data will be used as the reference to calculate the wastewater concentration and mass expected to be supplied to the new system. We know that the new houses and buildings that will be connected to the new plant will be much more water efficient (through a mandate for the new homes to use high efficiency water fixture and a mandate for the new buildings to treat and recycle wastewater onsite). It is, therefore, expected that customers connected to the new wastewater treatment plant will use half the volume of water used by customers connected to the old system. In order to estimate the new plant BOD5 and TSS mass loading, you assumed that, although people connected the new system will use half the amount of water, the mass of waste contributed by each person connected to both the old and new plants will be the same.

3. What is the BOD5 mass loading to the old plant? (answer will be given in the unit of lbBOD5/day)

4. What is the TSS mass loading to the old plant? (answer will be given in the unit of lbBOD5/day)

5. What are the average BOD5 and TSS mass loading per person to the old plant? In other words, in average, how much does each individual person contributes to the old plant BOD5 and TSS mass loading? (answers will be given in the unit of lb/person*day)

6. Based on the assumptions from the design team, what will the BOD5 and TSS mass loading to the new plant be? Remember that the mass of waste contributed by each person connected to both the old and new plants will be the same but that there will be more people connected to the new system.

7-What are the expected average BOD5 and TSS concentrations of the wastewater entering the new plant? (answer will be given in the unit of mg/l). Remember that the people connected to the new plant will use half the volume of

The city of Stay at Home counted 150,000 people in the 1970s, when its wastewater treatment plant was built. Because of a recent economic boom, the city has been growing at a fast rate and new developments will bring the total population to 350,000 people within 10 years from now. There is no more footprint available to expand the existing plant, which is land locked in the middle of an industrial zone. The city council, therefore, decided to build a new plant on the other side of the town. This new plant will be designed to treat the wastewater from the additional 200,000 people. You are the designer. Analysis of the last 5 years of operating data shows that the old plant received an average volume of 15 million gallon per day (MGD) with an average BOD5 concentration of 250 mgBOD5/L and an average TSS concentration of 270 mgTSS/L. This average BOD5 and TSS data will be used as the reference to calculate the wastewater concentration and mass expected to be supplied to the new system. We know that the new houses and buildings that will be connected to the new plant will be much more water efficient (through a mandate for the new homes to use high efficiency water fixture and a mandate for the new buildings to treat and recycle wastewater onsite). It is, therefore, expected that customers connected to the new wastewater treatment plant will use half the volume of water used by customers connected to the old system. In order to estimate the new plant BOD5 and TSS mass loading, you assumed that, although people connected the new system will use half the amount of water, the mass of waste contributed by each person connected to both the old and new plants will be the same.

1. How much water does each person connected to the old wastewater treatment plant consume? (answer will be given in the unit of gal/person*day)

2. How much water does each person connected to the new wastewater treatment plant is expected to use? (answer will be given in the unit of lbBOD5/day)

Part I. Indicate whether true or false (T or F).

__When performing flow profile analysis, calculations always proceed in the downstream direction. That is because water flows downhill, i.e., downstream.

__Subcritical flow is controlled by upstream conditions.

__The normal depth of flow, yn, is determined by solving Manning's equation. The critical depth of flow, yc, is determined by solving the Froude number equation set equal to 1.0. Normal depth, yn, varies with flow rate, channel geometry, channel slope, and channel roughness. On the other hand, yc varies only with flow rate, slope, and channel geometry.

__Critical flow (depth) occurs at the point of minimum specific energy, where the Froude number equals 1. The depth of flow at this point is termed the critical depth and is designated as yc. At depths below yc, the flow is classified as subcritical because the depth of flow is below (sub) the critical depth, and at depths greater than yc, the flow is classified as supercritical, because the depth of flow is greater than the critical depth.

__Flows are classified as subcritical, critical, or supercritical by comparing the uniform and critical depths of flow.

__The specific energy curve is obtained by plotting specific energy for a range of depth values (y values) for a given discharge in each channel. The curve falls in the first quadrant, with asymptotes of y=E (45o line) and the abscissa (E axis). The curve has three distinct portions corresponding to subcritical, critical and supercritical flow.

__Weirs and flumes are considered critical flow measurement devices since they force the depth of flow to pass through critical depth. They are indirect measurement devices since they do not directly measure velocity or the volume rate of flow but monitor a form of energy (depth or HGL).

__Subcritical open channel flow is controlled by downstream conditions. In the case of a backwater profile (M1 or S1), the control is some type of downstream constriction (such as an undersized road cross drain) that forces the water to pond to a greater depth.

__The specific energy diagram represents a plot of the sum of the pressure head (depth of flow) and velocity head terms for a range of y-values for a given discharge.

__Given an M2 flow profile, the specific energy increases in the upstream direction (opposite the direction of flow).

__The standard step method of flow profile analysis applies only to non-prismatic channels, while the direct step method applies to prismatic channels. For the standard step method, simply stated, the solution strategy is given y, find x. For the direct step method, the solution strategy is given x, find y.

__When a storm sewer pressurizes, the HGL is indicated by the water level in a manhole, which is above the crown of the downstream pipe. When a culvert pressurizes, the headwater at the inlet is above the crown of the downstream pipe.

__A necessary condition for uniform flow is a prismatic channel, which is a channel with constant cross-sectional geometry, roughness, and slope throughout the reach of interest.

__A control is a channel feature, usually structural, that regulates the state of flow. In the pure sense, a control forces a unique relationship between depth and discharge. The most ideal control is a critical control.

__Flow profile analysis involves determination of the nonuniform flow depth along a channel.

__Culverts operate under inlet or outlet control. Under outlet control, either the condition (e.g., depth of water) at the pipe outlet or the capacity of the pipe barrel regulates the discharge through the culvert. Under inlet control, the inlet capacity, i.e., how much water the inlet can pass subject to headwater depth, regulates the discharge through the culvert. Under inlet control, the pipe barrel can carry whatever discharge passes the inlet.

__Three assumptions underlying Manning's equation are that the flow is steady, uniform, and laminar.

__In the direct step method, the only unknown, given the depths at each end of a sub-reach, is the parameter Δx.

__Steady flow is flow that does not change with time at a point (cross-section) along a channel. Uniform flow is flow that does not change in space along a channel.

__An open channel that is hydraulically mild for one flow can be hydraulically steep for a different flow rate.

__Given an S1 flow profile, the specific energy increases in the downstream direction (direction of flow).

__According to DHEC guidelines, each pump in a duplex station must be designed to pump the average daily flow (ADF).

__One day while walking along Campus Creek (Rocky Branch), President Caslen passed the Catawba Street crossing and noted the depth of flow at a point was 1.50 feet. About 20 minutes later, he reached the Sumter Street crossing and noted the depth of flow there was 1.25 feet. He concluded the flow in the reach between the two crossings was steady and non-uniform. His conclusion was correct and defensible.

__The flow along a backwater curve (M1 or S1) decelerates (slows) in the downstream direction and is subcritical for both hydraulically mild and steep sloped channels. The flow along a drawdown curve (M2 or S2) accelerates (increases velocity) in the downstream direction and is supercritical for both hydraulically mild and steep channels.

__In open channels, flow control may be generated by structures at the upstream and downstream sections (ends of channel reach under consideration), but also may be continuous along the channel. When the control results from a structure at the upstream section, we say the control is upstream, i.e., the resulting profile is controlled by upstream conditions. When the flow control results from a structure at the downstream section, we say the control is downstream. When the flow control occurs continuously along the channel, the flow is under channel, or downstream, control.

• Discuss the advantages and disadvantages of adopting a licensing system for professional engineers similar to that for medical practitioners and teachers in the UK, and as applies to engineers in other countries (e.g. USA, Canada, Australia and some European states).

Include an examination of the role of the codes and rules of conduct of engineering institutions in the UK and their effectiveness in ensuring professional standards of work.

In an industrial project, a designer wants to use W16x57, F_y = 50 ksi, of various heights, as columns.

All columns will have fixed ends at the top and bottom (K=0.5).

Note that tables for W16 are not available in the Steel Manual, as it is a special use.

Use formulas, for Euler’s buckling stress; and for short and long columns, given in the PowerPoint.

Use radius of gyration, r_y, of 1.60 inches.

Calculate the design strength, F_C P_N, (Kips) of this shape for the 15’, 30’, and 45’ column heights used in that project.

A 6-lane two-way arterial road has a maximum flow of 6,000 vehicles per hour on one
direction. It is operating at 3,600 vehicles per hour at time, t=0. A collision occurs,
blocking the two lanes, and restricting the flow of the third lane to 1,800 vehicles per
hour. After 45 minutes, the MMDA and police have cleared the incident and traffic returns
to normal as soon as the queue has already dissipated.
a. Determine the maximum length of queue that occurred.
b. How long did it take to dissipate the queue?
c. What is the average delay per vehicle?
Show all necessary solutions and diagram.

You are provided the following information about a municipal wastewater treatment plant. This plant uses the traditional activated-sludge process. Assume the microorganisms are 55 percent efficient at converting food to biomass, the organisms have a first-order death rate constant of 0.05/day, have a maximum specific growth rate of 0.1/day, and the microbes reach half of their maximum growth rate when the BOD5 concentration is 10 mg/L. There are 150,000 people in the community (their wastewater production is 225 L/day-capita, 0.1 kg BOD5/capita-day). The effluent standard is BOD5 = 20 mg/L and TSS = 20 mg/L. Suspended solids were measured as 4,300 mg-MLSS/L in a wastewater sample obtained from the biological reactor, 15,000 mg-MLSS /L in the secondary sludge, 200 mg-MLSS /L in the plant influent, and 100 mg-MLSS/L in the primary clarifier effluent. SRT is equal to 4 days.

a. (0.5 points) What is the design volume of the aeration basin (m3 )?

b. (0.25 points) What is the plant’s aeration period (days)?

c. (0.25 points) How many kg of secondary dry solids need to be processed daily from the treatment plants?

d. (0.25 points) If the sludge wastage rate (Qw) is increased in the plant, will the solids retention time go up, go down, or remain the same?

e. (0.5 points) Determine the F/M ratio in units of kg BOD5/kg MLVSS-day (assume 0.6 g MLVSS per g MLSS)?

f. (0.25 points) Determine the critical SRT value.