What is liquefaction of sand? how can it prevented

Unlined trapezoidal channel to be excavated in fine sand soil to convey 350 ft3/s. The slope is 0.0025. Determine the width of the bottom and the depth of water of the cross section of the channel b and y.

A 200-acre catchment area contains 50 acres paved surfaces (C = 0.8), 100 acres buildings (C = 0.7), 40 acres open lawn space (C = 0.15). Determine the peak discharge Qp (cfs) by the Rational Method if the duration of the storm is 50 minutes. Assume 100-year return period storm. Use formulas/graphs from Houston City Manual.

TRP 631: HIGHWAY TRAFFIC OPERATIONS

An older four-lane freeway has the following characteristics:

• 11 ft lanes
• No lateral clearance
• 4.5 ramps/mile
• 5% truck( standard mix)
• Peak-hour factor = 0.90
• Rolling Terrain

The present peak-hour demand on the facility is 2,100 veh/h, and anticipated growth is expected to be 3% per year. What is the present LOS? What is the expected LOS in 5 years? 10 years? 20 years?. To avoid breakdown (LOS F), when will substantial improvements be needed to this facility, and/or alternative routes created? Good weather, no incidents, no work zones, and regular drivers may be assumed.

For steel member is subjected to cyclic loads,

The experimental results indicated failure at a number of cycles of 52 when the maximum stress is 1071 MPa. Also, failure at a number of cycles of 380,000 when the applied maximum stress is 506 MPA.

1. Find the fatigue equations for stress vs number of cycles using

σ = A N^B And σ = A (2N)^b

2) Plot on the same diagram both functions

3) Discuss the results of the two plots.

4) Find the number of cycles to failure when the maximum stress is 950 MPa in both functions

I need a full explanation of - Types of Road maintenance and tools

Please include at least 2 references,thanks.

2 There are two (2) laboratory tests can be conducted to determine the coefficient of soil permeability which is falling head test(for fine grained soil) and constant head test(for coarse grained soil). Based on your understanding about soil permeability, justify the difference of these two tests in details by using your own word. Provide the justification with references and the answers are limited to three pages only.

1) why is the difference between an avoidable delay and an unavoidable delay important to a contractor? 2) What is the difference between a calender day and a working day? 3) Why would it be necessary and desirable to perform resource leveling for a construction schedule? 4) In which parts of a schedule should a contractor share the most detail with an owner? 5) As a contractor, what concern would you have regard cost and productivity if an owner directed you to use overtime to catch up on a scehdule?

1- A 20-cm well penetrates 25 m below the static water table. After 24 hours of pumping out at the rate of 800 lpm, the water level in a test well at 80 m from the pumping well is lowered by 0.53 m and in a test well 20 m away 2.11 m. Find the coefficient of transmissibility of the aquifer.

2-What is the nature of ground water flow? State the law governing the flow with limitations, if any.

3-A well penetrates into an unconfined aquifer having a saturated depth of 50 m. The discharge is 250 1pm at 8 m drawdown. What would be the discharge at 10 m drawdown. The radius of influence in both the cases may be taken as same.

4-Describe the method of construction of open wells:
(i) in a soil where a clayey stratum is encountered.
(ii) in rocky sub-strata.

5 -A tubwell penetrates fully an unconfined aquifer. Calculate the discharge from the well in lpm from the following data:

Diameter of the well 30 cm

Drawdown in the well 3 m

Effective length of the strainer under the above drawdown 10 m

Coefficient of permeability of the aquifer 40 m/day

Radius of zero drawdown 300 m

please compare the plane strain fracture toughness and Charpy test

Assignment I
Question 1: Prepare a report explaining ITS technologies used in transport sector in Japan, Europe and USA (in 2000 words).
Question 2: How you can apply ITS technologies to improve transportation situation in USA (in 500 Words)?
Question 3: How TSM and TDM are used to reduce traffic problems in Japan, China, Europe and Singapore (in 1000 words)?
Question 4: How Bus Rapid Transit (BRT) is used in Bogota and Curitiba to solve transport problems (in 1000 words)?

7) You are working on a concrete mix design that requires each cubic yard of concrete to have a 0.45 water–cement ratio,2100 lb/yd3 of dry gravel, 250 lb/yd3 of water, and 5% air content. The available gravel (NMS = ¾”) has a specific gravity of 2.6 , moisture content of 2.5% and absorption of 4.5%.The available sand has a specific gravity of 2.4, a moisture content of 2.5% and absorption of 2%. Air entrainer is to be included using the manufacturers specification of 0.1 fl.oz / 1% air / 100 lb cement. For each cubic yard of concrete needed on the job, calculate the weight of cement, moist gravel, moist sand, and water that should be added to the batch. Summarize and total the mix design when finished. 8) Design a concrete mix for the following conditions and constraints using the absolute volume method: Design Environment : Non-air entrained concrete will be used to cast Concrete frame. Required design strength(5000 psi) Minimum dimension (10 in.) Minimum space between rebars (1.5 in.) Minimum cover over rebars (2.5 in.) Standard deviation of compressive strength (600 psi) , (25 samples) Available Materials Cement Type II , moderate exposure Coarse aggregate Nominal Maximum size 1 in. river gravel (round) Bulk oven dry specific gravity =2.65, absorption = 3%, oven dry density 110 pcf , Moisture content 2%. Fine aggregate : Natural sand , Bulk oven-dry specific 2.5 , Absorption = 1% , Moisture content = 0.5% , Fineness modulus = 2.80

7) You are working on a concrete mix design that requires each cubic yard of concrete to have a 0.45 water–cement ratio,2100 lb/yd3 of dry gravel, 250 lb/yd3 of water, and 5% air content. The available gravel (NMS = ¾”) has a specific gravity of 2.6 , moisture content of 2.5% and absorption of 4.5%.The available sand has a specific gravity of 2.4, a moisture content of 2.5% and absorption of 2%. Air entrainer is to be included using the manufacturers specification of 0.1 fl.oz / 1% air / 100 lb cement. For each cubic yard of concrete needed on the job, calculate the weight of cement, moist gravel, moist sand, and water that should be added to the batch. Summarize and total the mix design when finished.

You have wastewater plant discharging into a clean river. The BOD of the Wastewater flow is 300 mg/L, the wastewater flow is 15 m3/sec, the river flow upstream of the mixing point is 120 m3/sec and BOD upstream of river is 0. The DO of the river at the mixed point is 8 mg/L and the saturation DO in the river would be 10 mg/L, the deoxygenation rate coefficient is 0.30/day and the reaeration constant is 0.90/day. The river is flowing 50 km/day and has no other BOD sources. (A) Find the critical distance downstream where BOD is a minimum, (B) Find the minimum DO at this point. (C) Draw a curve roughly to show the DO curve shape from the location of the mixing point downstream: your Y axis should be DO, your X axis should be distance, show the DO saturation line, the Do, the critical point distance, and DOmin.