A lumber floor joist is designed from Douglas Fir-Larch number 1 and better. The joist is simply supported over a span of 12' and is part of a floor system that includes repetitive joist framing at 16" o.c and a plywood subfloor. Assume dry and normal temperature service conditions. The joist carries 25 plf of dead load and 55 plf of live load. Size the joist.

Humans have populated regions in which the geomorphic settings pose hazards for construction and engineering projects. Discuss the extent to which the potential hazards are caused by intrinsic versus extrinsic thresholds. Build your discussion around comparing and contrasting humid, semi- arid, glaciated, and periglacial environments.

hello guys this is regarding a construction safety class, under the civil engineering degree, hope to hear your thoughts and comments

1. Construction Management, Inc. (CMI) has a safety awareness program, but it does not seem to be working. CMI’s president and his two vice presidents developed the program themselves and implemented it company wide six months ago. Unfortunately, they have seen no decrease in the number of accidents and incidents. What possible problems do you see with CMI’s safety awareness program? What changes or improvements would you recommend?

2. Employees of Bearden Construction Company have begun to complain regularly about Josh Randall. They say that his behavior has become unpredictable and that he blows up at the slightest provocation. One employee even said, “This guy is going to hurt somebody.” To each complaint, the supervisor’s response is the same: “Be patient. Josh is a good man. He’s just dealing with some personal problems right now. He’ll get over it.” What do you think of the supervisor’s response to employee concerns? How do you think this situation should be handled?

The traffic volume from A to B is 4500 veh/hr. two routes are available from A to B. Route I is 6 mi. long, design speed is 60mi/hr, link performance function is t1(x)=t1(0)+4x; Route II is 3 mi, design speed is 45mi/hr, link performance function is t2(x)=t2(0) +x2(where t(0) is the free-flow travel time, and x is traffic flow on the route in 1000 veh/hr). a. Determine the travel time and flows using user equilibrium method; b. Determine the travel time and flows using the system optimization method. Compare the total vehicle hours obtained from both methods.

Q5. Derive an equation relating the sequent depths in a rectangular channel which has a bed slope of S_o. Assume that y₂=5L_j where L_j is jump length and shape of the jump between upstream and downstream is trapezoid. Draw the control volume and show all variables. Hint: Apply momentum equation and take into account the weight force.

USING UNITED STATES IBC CHAPTER 8:

1. Define the following:
   a. Shallow Foundation:
   
   b. Expansive Soil:

c. Foundation Drain:

2. Describe the situations when a sub-surface investigation for Ground-Water table is required and when it can be waived.

3. In the absence of a load-bearing test for foundation to be built on a crystalline bedrock, a vertical foundation pressure up to _______ may be used in design.
   
   A. 3000 psf                                 B. 4000 psf                          C. 6000 psf                          D. 12000 psf

4. For concrete used in foundation, the specified minimum compressive strength should be _________.  
   
   A. 3000 psi                                  B. 3500 psi                          C. 4000 psi                          D. 5000 psi
   
5. For precast pre-stressed deep foundations elements, the concrete cover must be at least _____ inches.

A. 1.5 inches                              B. 2.0 inches                       C. 2.5 inches                       D. 3.0 inches     

6. The minimum depth of a footing placed below undisturbed ground surface shall be _____ inches.

A. 12 inches                                B. 15 inches                        C. 18 inches                        D. 24 inches

7. Code waives the frost protection requirement of foundation for a free-standing building with maximum area of ______.

A. 400 sq. ft.                               B. 600 sq. ft.                       C. 800 sq. ft.                       D. 1000 sq. ft.

8. In the absence of design, the width of concrete footing supporting a 2-story light-frame construction shall be accepted to be _______.

A. 12 inches                                B. 15 inches                        C. 18 inches                        D. 24 inches

9. The edge thickness of plain concrete footings supporting walls other than light-frame construction shall not      
      be less than _______.

A. 6 inches                                  B. 8 inches                          C. 10 inches                        D. 12 inches

           10.   For Type ____ buildings, timber footings are allowed by the code.

     A. Type II                                        B. Type III                            C. Type IV                            D. Type V

explain Water footprint concepts and its challenges in Oman.

In general the it is better to mine a tunnel upgrade (uphill) rather than downgrade because the upgrade has (a) more favorable discontinuity orientation (b) water in tunnel will drain away from tunnel face (c) gravity better assists in mining tunnel face (d) downgrade from tunnel face speed up muck removal (e) all answers apply

The answer needed is only for part C.

A) Willow and Stevens are two-way streets in an urban area. A four-phase operation is used for the intersection of Willow and Stevens with a cycle time of 110 seconds, including 15 sec Green for the left turn (LT) vehicles on each street. If the green time for the through (TH) vehicles on Willow is 30 sec, determine the green time for the through (TH) vehicles on Stevens and construct the signal timing cut-out diagrams for vehicles only without considering pedestrians. Assume a clearance (Yellow 3 sec + All Red 2 sec) time of 5 seconds when the green light is switched between Willow and Stevens (but do not use the clearance time when the signal changes from LT to TH on the same street. B) The width of Stevens Avenue is 52 feet. How long should be the Flash Don’t Walk (FDW) duration if the walking speed of pedestrians is 4 feet/sec?

C) If the minimum headway is 2 sec, delay per phase is 4.6 sec, and there are two through lanes and one left-turn lane on Willow in each direction, how long should be the cycle time if the combined (LT + TH) traffic volume on this street is 3000 vehicles/hour?

What is plumbing ? What are the requirements for doing plumbing works and moisture insulation in bathrooms. Also how are installed and inspected later, what are the risks associated with their installation and what would be the safety measures then? What is the right sequence to follow while installing such materials?

Compare work place safety in the 1890’s and early 20^th century, as compared to today safer working conditions

Please explain, be as detailed as possible

For a dual-media filter with 0.5 m of anthracite coal and 0.3 of sand. Other data for anthracite: specific gravity is 1.67, porosity is 0.5, d₉₀ grain size is 1.5 mm. Other data for sand: specific gravity is 2.65, porosity is 0.4, d₉₀ grain size is 0.9 mm. The water temperature is 20C, so the mass density of water (ρ) is 998.2 kg/m³ , density of sand is 1650 kg/m³ , density of anthracite coal is 1506 kg/m^3, the absolute viscosity is 1.002 x 10^-3 kg/m-s. Assuming a 30% margin of safety for backwash, calculate the following:

a) the recommended backwash rate for the filter (gpm/sf)

b) the pressure drop through the filter during fluidization (psi)

Note: multiply (L/m²-s) by 1.473 to get gpm/sf. Multiply (N/m²) by 0.000145 to get psi.

Two discharge wells (1 and 2) penetrating an unconfined aquifer are pumped at constant rates of 3,000 and 500 m^3 per day , respectively. The steady-state head (i.e., water table height) measured at an observation well is 40 meters . The observation well is 50 meters from well 1 and 64 meters from well 2. The water table height measured at a second observation well is 32.9 meters , which is located 20 meters from well 1 and 23 meters from well 2. Determine the aquifer permeability K (in m/day).

Q4. A rigid strip footing is constructed on a layered soil deposit, as shown in the figure.

Before construction of the footing, laboratory tests on a saturated clay sample, taken at a depth of 6 m below the ground surface, gave the following results:

• Compression index: C_c = 0.3,
• Recompression index: C_r = 0.08  
• Over consolidation ratio: OCR = 1.5
• Water content: w = 25%
• Specific gravity: G_s = 2.65

Saturated unit weight of clay: g_sat = 19.5 kN/m³

1. Calculate the settlement of the footing due to deformation of the sand layer only. Sand properties are as follows:         

• Total unit weight: g_t = 18 kN/m³             
• Young’s modulus: E_s = 30 MPa                 
• Poisson’s ratio: n = 0.25

2. Based on the elastic theory (Boussinesq’s equation), calculate the change in vertical stress at point A long time after applying the surcharge load.
3. Using the theory of 1-D consolidation, calculate the total settlement of this rigid footing due to consolidation of the clay layer only, long time after applying the total load.