CIV E 401 Final Notes PDF

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CIV E 401 Final Natural Hazards ● Floods, Droughts, El Nino, Wind, Design Loads, Earthquakes ● What Natural Hazards do CE’s commonly address? ○ Floods, Droughts, Coastal Erosion - CIVIL ○ Geotechnical (Landslides, Subsidence, Sinkholes) - SOILS ○ Wind Events, Earthquakes - STRUCTURAL ● Floods ○ Natural events, not completely preventable ○ Cities built near rivers for water, irrigation and navigation, but floods are an associated risk ○ 100-year flood: used for normal design, 1% chance in any year ■ Implies the possibility of a larger flood at larger recurrence interval ■ Implies the possibility to rebuild the flood-control infrastructure approximately every four generations ○ Ultimate flood control design uses 10,000 year interval ■ PMP and PMF ● Probable maximum precipitation and flood ○ Occurs… ■ Rains unusual amount, rains unusual amount in already wet basin, rains unusable amount in a basin made more impermeable ○ Civil’s Role: ■ Control (design and construction of flood control structures) ■ Mitigation/proofing ● Reducing runoff/absorbed water: bioswales, porous pavement ■ Fighting carried out during flood event ■ Insurance ○ Droughts ■ Periods with insufficient rain, enough to jeopardize life and property ■ Are natural, will always happen ■ More frequent and more intense in arid and semiarid regions ■ Civil’s Role: ● Building multiannual storage reservoirs and societies resort to water conservation practices ○ El Nino ■ Produces droughts coupled with floods ■ Natural phenomenon whose cause is not known with certainty ■ Warmer than normal sea surface waters along the eastern tropical pacfic ■ Named for “the child jesus,” peruvian fisherman ■ Return period: 2-7 years, average = 4 years (14-22 months) ● Two consecutive events do not behave the same way ● Strong events: 8-15 year intervals

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■ Typically alters the magnitude and frequency of floods and droughts Wind ■ Normal wind storms and hurricanes ■ Tornadoes are not normally designed for due to low annual probability at any one location and the cost of construction ■ “Ultimate” wind speeds range from 90 mph to 110 mph, to 150-180 mph in hurricane regions ● 3 second gust ● Wind pressures dependent on wind speed squared ■ Typical Damage: roof uplift and leeward suction Design Loads ■ ASCE Minimum Design Loads and Associated Criteria for Buildings and other Structures ■ Dead, Live, Soil, Hydrostatic, Flood, Tsunami, Snow, Rain, Ice Seismic, Wind

Earthquakes ● What are they? ○ Earth’s crustal plates that move along major faults ○ Earthquake prone regions (along plate boundaries): west coast, alaska, new madrid (ohio), charleston, hawaii ● Overview ○ Strike-Slip ■ Lateral movement with minimal vertical displacement ■ California’s major fault ● Slip rate is roughly 1” per year and builds up pressure until relieved ● San Andreas fault accounts for 75% of plate movement ○ Dip-slip ■ Plates are moving apart from each other ○ Thrust ■ Plates are pushing against each other, one plate passing under the other ■ Responsible for largest earthquakes ○ Energy ■ Earthquakes transmit “body” waves - deep, “surface” waves - shallow ● Body waves ○ Primary waves ■ 11000 mph ○ Secondary waves ■ 60% of P speed ○ Measurement ■ Magnitude and Intensity ● Magnitude: seismographs ● Intensity: effects of earthquake at surface

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There are 100,000 human detectable earthquakes each year, on average, 19 major earthquakes per year (7.0 and above) Design ○ Does not use magnitude or intensity scales ○ Spectral response that depends on structure location and type ○ Based on “Equivalent lateral force” procedures, uses %g for design ■ Based upon 2% probability of exceedance in 50 years Vulnerable Structures ○ Unreinforced Masonry ■ Red brick, built prior to 1933 ○ Non Ductile Concrete ■ Built prior to late 1970’s ○ Concrete Component Buildings ■ Tilt-Up and Precast ■ Built Prior to mid 1990’s ○ Soft Story/Weak Story ■ Built prior to 1980’s Soils Damages ○ Subsidence, Landslide, Faulting, Liquefaction

Construction Longevity ● What is Longevity? ○ Long, age ○ Buildings/Structures that are durable and last for lifetimes ● Wood Longevity ○ Enemies: weathering, UV light, insects, fungi ■ Fungi need: ● Temperature, oxygen, food, moisture ○ Wood buildings can last hundreds of years if protected ○ Solutions: ■ weathering/UV light: ● paint/stain ■ Insects ● Wood and soil dry ● Chemical soil treatment ● Pressure treated lumber ■ Fungi ● Keep wood dry ● Pressure treated lumber ● Decay resistant species ○ Cedars, redwood, oak ● Non-resistant species ○ Douglas fir

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○ Southern pine ■ Manufactured wood- very susceptible to water damage Steel Longevity ○ Enemies: air, water, chlorides (road salts, ocean salts, natural salts) ○ Rust (oxidation) ■ Chemical reaction between iron, water, oxygen ● Iron atoms leave steel and form iron oxide ■ As rusts, expands and delaminates ○ Solutions: ■ Coatings (lowest) ● paint , epoxy ■ Galvanization (medium) ● Zinc coating ○ Hot dipping ○ Electro-galvanizing ○ Tumbling ■ Cathodic Protection (medium/high) ● Passive - zinc anode, similar to galvanization ● Active- electric current ■ Stainless Steel (best protection) ● Common for small items (nuts, bolts, rods, etc) ● Not common for large elements Concrete/CMU Longevity ○ Enemies ■ 1- steel corrosion ● Oxidation of reinforcing steel ■ 2- concrete sulfate attack ● Soluble sulfates ■ 3- freezing ● Water in concrete expands when frozen, problem in cold weather areas ○ Solutions ■ 1-steel corrosion ● Increased concrete “cover” ● Dense concrete (fly ash, low water/cement) ● Rebar/PT ● Cathodic Protection ■ 2- sulfate attack ● Resistant type V cement ● Dense concrete ■ 3- freeze thaw ● High strength concrete ● Air entrained

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Consultants to assist ■ Metallurgist, corrosion engineer, materials scientist, chemist, soils engineer

Engineering Licensing ● Board for Professional Engineers, Land Surveyors, and Geologists ○ Engineering in Training Certificate (or FE) ■ Pass FE exam ● Computer based, 6 hours, may be taken once per quarter, may be taken in 2nd half of 3rd year ● After passing FE exam, apply for EIT certification ○ Licensed CE ■ Can go by: Professional engineer, civil engineer, licensed engineer, registered engineer, consulting engineer ■ Requirements ● EIT certificate, BS minimum, pass NCEES CE exam (8 hours), 2 years work experience, apply yo BOPELSG, Pass take-home exam on california laws, pass california 2.5 hour seismic and surveying exams ■ Options ● “Depth” portion ○ Concentrations: construction, geotechnical, structural, transportation, water resources and environmental ○ SE exam ■ Structural engineer ■ Requirements: ● CE license, 3 years additional work experience, 16 hour exam ○ Geotechnical Exam ■ Soils engineer, geotechnical engineer ■ Requirements: ● CE license, 4 years additional work experience, 8 hour california based exam ● Renewal ○ Periods ■ Every year: 7 states ■ Every 2 years: 41 states (california) ■ Every 3 years: 2 states ● Continuing Education ○ Professional Development Hours ■ “An activity to maintain, improve, or expand the skills and knowledge relevant to the engineer’s discipline” ● Examples: college course, offsite seminar/workshop/lecture, in office web-based seminar, in office technical product presentation,

engineering convention, professional society activities, technical article preparation, self study, self paced web-based course ○

States ■ 8 states have no requirement (hawaii and california) ■ 2 states have 4 to 8 hours/year (florida and virginia) ■ 40 states have 12 to 15 hours/year

Engineering Management ● Engineering Management ○ “Hard skills” - estimating, scheduling, technical design ○ “Soft skills” - effectively manage a team, including admin staff, drafters, engineers, technicians, contractors, etc. ○ Triple C model ■ Communication, cooperation, coordination ○ Who will you manage/supervise someday and when/how? ■ Admin: immediately ■ Drafters: immediately ■ Engineers: after 4-10 years ■ Technicians: directly/indirectly ● Techs - installation/material testing, soils testing, surveying ■ Contractors: directly/indirectly ● Management Structure ○ Owner/department head ○ Lead engineer/project manager ○ Project engineer ○ Staff engineer ○ Entry engineer ● Management Duties ○ Hiring, fiiring, salary, performance reviews, bids, proposals, firm/department budgeting, staff oversight, quality control, reports, etc. ● Design Project Phases ○ Schematic design ■ Determine overall project characteristics ○ Design development ■ Performs initial calculations of primary systems, solves major obstacles ○ Construction documents ■ Completes full detailed design calculations and drawings, ready for construction ■ Construction drawings, engineering calculations, specifications ○ bidding ■ Respond to bidder questions and review bids ○ Construction administration

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Review contractor submittals, respond to contractor questions and problems, devise solutions for construction errors, review testing/special inspection reports, perform construction observation, review payment requests, monitor subcontractors, etc.

Engineering Ethics ● ASCE Code of Ethics ○ Fundamental Canons ■ Canon 1: engineers shall hold safety paramount ■ Canon 2: engineers shall perform services in areas of their competence ■ Canon 3: engineers shall issue public statements only in an objective and truthful manner ■ Canon 4: engineers shall act in a professional matter, faithful client ■ Canon 5: engineers shall build their professional reputation and shall not compete unfairly with others ■ Canon 6: engineers shall act in a manner as to uphold the honor, integrity, and 0 tolerance for bribery, fraud, corruption ■ Canon 7: engineers shall continue professional development throughout their careers ■ Canon 8: engineers shall treat all persons fairly and not discriminate ● Board of Professional and Licensed Engineers Rules ○ “BOPELSG” ● Ethics Case Studies ○ Ideas to consider: public welfare, areas of competence, truthful statements...