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by P. E. Allan G. Abubakar (Author)
Visit www.usefulequations.com to purchase book and HP 35s pre-programmed calculator package. The equations in this book are relevant to the following subjects: Geotechnical -Moisture content, dry density, void ratio, degree of saturation, relative density of soil, borrow soil, flow net, laboratory permeability tests, and effective stress -Shear strength and angle of internal friction for triaxial test -Net and ultimate bearing capacities of square, continuous, and circular footings with or without water table -Active, passive, and at-rest lateral forces per unit length of wall with surcharge load and water table, and lateral force per unit length of wall for sloping backfill and vertical wall -Gross and net bearing capacity of mat foundation in saturated clay, and depth of fully compensated mat foundation -Factor of safety against overturning and sliding of retaining walls, maximum stress at the toe, and minimum stress at the heel -Settlement of normally consolidated clay with up to 4 layers of soil given surcharge load, settlement at the center and corner of mat foundation, time rate of settlement, slope stability in saturated clay, and cyclic stress ratio -2-strut braced cut for sand, soft to medium clay, and stiff clay -Skin friction resistance, end-bearing and allowable capacities of single pile in sand or clay Water Resources and Environmental -Pitot tube, venturi meter, and orifice -Reynolds number, friction factor, head loss using Darcy-Weisbach equation or Hazen-Williams equation, Bernoulli equation with 2 different pipe sizes, pump head, and head loss due to fittings -Open channels using Manning equation for circular, rectangular, and trapezoidal channels -Flow rate and velocity of flow for circular channel when flowing full or partially full just by entering diameter of pipe, depth of water, Manning's n, constant, and slope of energy line (no need to look up tables ) -Flow rate and velocity of flow for trapezoidal channel just by entering depth of water, base width of channel, side slope horizontal, Manning's n, constant, and slope of energy line -Chemical feed rate -Rapid mixing -Overflow rate -Detention time -Weir loading rate Transportation -Sight distance and stopping sight distance -Radius of curve, tangent of curve, length of curve, middle ordinate, and external distance of horizontal curve -Stopping sight distance, passing sight distance, curve elevation, stationing of highest or lowest point of curve, and vertical clearance -Flexible and rigid pavement design Structural -Maximum moment of simply supported and cantilever beams, moment of inertia for I-beam, T-beam, and inverted T-beam using parallel axis theorem, maximum bending stresses, and deflection of beam This book contains 200 equations with keystrokes included for HP 35s and HP 33s calculators plus 96 sample problems with step-by-step solutions.
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