Fenômenos Químicos e Físicos

Prévia do material em texto

<p>Chapter 1</p><p>1.1 Two solid cylindrical rods AB and BC are welded together at B and loaded as Problem 1.1 shown. Determine the magnitude of the force P for which the tensile stress in rod AB is twice the magnitude of the compressive stress in rod BC 75 mm 50 mm 120 kN B C A P 120 kN 750 mm 1000 mm ABC Equating 5AB to P= 2 KN Problem 1.2 1.2 In Prob. 1.1, knowing that P = 160 kN, determine the average normal stress at the midsection of (a) rod AB, rod BC. 1.1 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Determine the magnitude of the force P for which the tensile stress in rod AB is twice the magnitude of the compressive stress in rod BC. (a) Rod AB. 75 mm 50 mm 120 kN B C A P=160kN 120 kN 750 mm 1000 mm (b) Rod BC. KN i.e. 80 KN compression. MPa Proprietary Material. 2009 The McGraw-HIII Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.3 1.3 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Knowing that the average normal stress must not exceed 175 MPa in rod AB and 150 MPa in rod BC, determine the smallest allowable values of and A Rod P = N 300 mm 4P B m mm 250 mm d2 Rod C P = 30 KN = N = P 4P = m d2=15.96 mm Problem 1.4 1.4 Two solid cylindrical rods AB and BC are welded together at B and loaded as shown. Knowing that d, 50 mm and d2 30 mm, find average normal stress at the midsection of (a) rod AB, (b) rod BC. A Rod AB . 70 300 mm = 1.9635x10 d1 B = Pa 250 mm (b) Rod BC. P = 30 = 30x C = 30 kN MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>1.5 A strain gage located at C on the surface of bone AB indicates that the average Problem 1.5 normal stress in the bone is 3.80 MPa when the bone is subjected to two 1200-N forces as shown. Assuming the cross section of the bone at to be annular and knowing that its outer diameter is 25 mm, determine the inner diameter of the bone's 1200 N cross section at C. A 5 = A P Geometry: C = B 1200 N 10-3 m d2=14.73 mm Problem 1.6 1.6 Two steel plates are to be held together by means of 16-mm-diameter high- strength steel bolts fitting snugly inside cylindrical brass spacers. Knowing that the average normal stress must not exceed 200 MPa in the bolts and 130 MPa in the spacers, determine the outer diameter of the spacers that yields the most economical and safe design. At each bolt location the upper plate is pulled down by the tensile force Pb of the balt. At the same time the spacer pushes that plate with a compressive force Ps. In order to maintain equilibrium For the bolt, or For the spacer, or Equating Pb and Ps, = = 130 (16)</p><p>Problem 1.7 1.7 Each of the four vertical links has an 8 36-mm uniform rectangular cross section and each of the four pins has a 16-mm diameter. Determine the maximum value of the average normal stress in the links connecting (a) points B and (b) 0.4 points C and E. C 0.25 in 0.2 B Use bar ABC as a free body. 20 kN 0.025 A A B C FBD = (0.040) + 0.040 ) = N Link BD is in tension. MB = - = For = N Link CE in Net area of one link for tension = ) = m. For two parallel links, Anet = Tensile stress in link BD. (a) = = Area for one link in pression = (0.008)(0.036) = For two parallel (b) = 21.70 = 21.7 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.8 1.8 Knowing that the central portion of the link BD has a uniform cross-sectional P area of 800 determine the magnitude of the load P for which the normal stress A in that portion of BD is 50 MPa. P A 30° B 0.7m 1.4m 30° B 1.4 m = FBD 1.92 m 1.4m 1.92m C D 1.4m Y ID Use Free Body AC for statics. 0.56 m 0.56 m 0.56 2.00 2.00 N P= Problem 1.9 1.9 Knowing that link DE is 25 mm wide and 3 mm thick, determine the normal stress in the central portion of that link when (a) 0 0, (b) 0 = 90°. 100 min 100 mm 300 Use member CEF as a free body E 50 mm D = C 200 mm 150 min A F 0 = E C Cx FDE (a) = FDE = -320 N Cy = MPa F 240N = = = - 2.13 MPa</p><p>Problem 1.10 1.10 Link AC has a uniform rectangular cross section 3 mm thick and 12 mm wide Determine the normal stress in the central portion of the link. B Free Body Diagram of Plate 75 mm 960 N e By Bx 150 mm 175 mm 960N B A 960 N 150mm 30° C 960 N A Note that the two 960-N forces FAC Form a couple of moment = = 144 - = 0 FAC = 665.1 N Area of link: AAE = (3mm)(12 mm) = 36 mm2 Stre = FAC = 665.1 = 18.475 MPa = 18.5 MPa AAC 36 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.11 1.11 The rigid bar EFG is supported by the truss system shown. Know- ing that the member CG is a solid circular rod of 18 mm diameter, determine the normal stress in A B C 0.9 Using portion EFGC B as a free body D E F G FAB - 15=0 FAE = 25 KN 15 1.2 1.2m 1.2 Using beam EFG as a Free body FAB B FAE = E F G FDE E Cross sectional area of member CG Acc = d2 = (0.018) = FAE FBF Normal stress in CG. E F G = = 25 = 98.3 MPa For Acc Problem 1.12 1.12 The rigid bar EFG is supported by the truss system shown. Deter- mine the cross-sectional area of member AE for which the normal stress in the member is 105 MPa. A B C 0.9 Using partion EFGCB as a free body D E F G 1.5 FAE = 15 1.2 1.2m Stress in member AE GAE 105MPa FAB B = FAE FAE E F G F DE AAE -6 15 KN 105x10 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.13 1.13 A couple M of magnitude 1500 N . m is applied to the crank of an engine. For the position shown, determine (a) the force P required to hold the engine system in equilibrium, (b) the average normal stress in the connecting rod BC, which has a 450- P uniform cross section. P Use piston, rod, and crank together as free body. Add H 200 mm wall reaction H and bearing B reactions Ax and Ay. 80 mm M = A (0.280 m)H - 1500 = M 60mm H= 5.3571x103 N Ax Use piston alone as free Ay P body! Note that rod is a two-force hence the direction H of force FBC is known. Draw the force triangle and solve for P and by FBC P proportions. l 200 + 208.81 mm P 200 = 17.86 N 60 H 60 H (a) 17.86 KN FBC 208.81 = : H 60 N -6 Rod BC is a compression member. Its area is 450 x10 m Stress, = = - = Pa A (b) = - 41.4 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.14 1.14 An aircraft tow bar is positioned by means of a single hydraulic cylinder connected by a 25-mm-diameter steel rod to two identical arm-and-wheel units DEF. The mass of the entire tow bar is 200 kg, and its center of gravity is located at For the position shown, determine the normal stress in the rod. Dimensions in mm 1150 D 100 C 450 B F E 250 850 500 675 825 FREE BODY - ENTIRE TOW BAR: (9.81 = 1962.00 N Ay W 1150 mm Ax G . A B 850R - = A 850 mm R = 2654.5 N FREE BODY - BOTH ARM & WHEEL 100 tan = 675 100 mm 450 mm = Ex E = 2439.5 N (COMP.) to 675mm 2439.5N = R =2654.5 = - Pa 4.97 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.15 1.15 The wooden members A and B are to be joined by plywood splice plates that will be fully glued on the surfaces in contact. As part of the design of the joint, and knowing that the clearance between the ends of the members is to be 6 mm, 15 determine the smallest allowable length if the average shearing stress in the glue is not to exceed 700 kPa. There are separate areas that ave glued. Each of these areas transmits one half the 6 mm the 15 KN load. Thus F = = = 7500 N 75 mm 15 F F P P F F Let I, length of one glued area and W = = 0.075 m be its width. For each glued area, Average shearing stress: A The allowable shearing stress is Pa Solving for F 7500 - = 142.85 mm Total length L = + (gap) + l = 292 mm Problem 1.16 1.16 When the force P reached 8 kN, the wooden specimen shown failed in shear along the surface indicated by the dashed line. Determine the average shearing stress along that surface at the time of failure. 15 mm P Area being sheared A = = 1350 = 1350 Steel Wood 90 min Force P= N Shearing stress = A = Pa=5.93 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.17 1.17 Two wooden planks, each 12 mm thick and 225 mm wide, are joined by the dry mortise joint shown. Knowing that the wood used shears off along its grain when the average shearing stress reaches 8 MPa, determine the magnitude P of the axial load 16 mm which will cause the joint to fail. 16 mm Six areas must be sheared off when the joint Each of these 25 mm 50 mm P' P areas has dimensions 16 mm 12 mm, 50 25 225 mm its area being A = At Failure the force F carried by each of areas is = x 1536 N 1.536 KN Since there are six failure areas P= 6F (6)(1.536) = 9.22 Problem 1.18 1.18 A load P is applied to a steel rod supported as shown by an aluminum plate into which a 12-mm-diameter hole has been Knowing that the shearing stress must not exceed 180 MPa in the steel rod and 70 MPa in the aluminum plate, 40 mm determine the largest load P that can be applied to the rod. 10 mm For the steel rod, 8 mm A, = 12 mm = P = N For the aluminum plate, A2= = = A2 P2 = = N The limiting value for the load P is the smaller of P, and P2. P= N</p><p>Problem 1.19 1.19 The axial force in the column supporting the timber beam shown is Determine the smallest allowable length of the bearing plate if the bearing stress in the timber is not to exceed 3.0 SOLUTION L = LW Solving for mm 178.6 10-3 m 178.6 mm Problem 1.20 1.20 The load P applied to a steel rod is distributed to a timber support by an annular washer. The diameter of the rod is 22 mm and the inner diameter of the washer is 25 mm, which is slightly larger than the diameter of the hole. Determine the smallest allowable outer diameter d of the washer, knowing that the axial normal stress in the steel rod is 35 MPa and that the average bearing stress between the washer and the d timber must not exceed 5 MPa. rod: 22 mm Pa P = N Washer: 6b = Pa Required bearing area: = = But, = = d= m d=63.3 mm</p><p>Problem 1.21 1.21 A 40-kN axial load is applied to a short wooden post that is supported by a concrete footing resting on undisturbed soil. Determine (a) the maximum bearing stress on the concrete footing, (b) the size of the footing for which the average P bearing stress in the soil is 145 kPa. 120 mm 100 mm (a) Bearing stress on concrete footing. 40 40x103 N = mm2 = b A = Pa 3.33 MPa (b) Footing area. 40 N 5= 145 = 45x103 Pa A 40x103 = = 0.27586 145x103 Since the area is square, b= = = 0.525 m b=525 mm Problem 1.22 1.22 An axial load P is supported by a short W200 X 59 column of cross-sectional area A = 7560 and is distributed to a concrete foundation by a square plate as shown. Knowing that the average normal stress in the col- umn must not exceed 200 MPa and that the bearing stress on the concrete a PI a foundation must not exceed 20 MPa, determine the side a of the plate that will provide the most economical and safe design. For the column or = For the axa 6 20MPa A = = Since the plate is square = a= = = 0.275 M 275 mm Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced. or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.23 1.23 A 6-mm-diameter pin is used at connection C of the pedal Knowing that P = 500 N, determine (a) the average shearing stress in the pin, (b) the nominal bearing stress in the pedal at C, (c) the nominal bearing stress in each support bracket 75 mm 9 mm 300 mm A B Draw free body FAB A P 125 mm diagram of ACD. P Since ACD is a D force member, C C the reaction at C D is directed toward point E, the intersection 5 mm of the lines of action of the of her two forces. From geometry, = 325 mm. +1 125 325 = = (a) = = Pa MPa Apin 1300 (b) = = dt = 1/C Ab = 2dt C 1300 = Pa 1.24 Knowing that a force P of magnitude 750 N is applied to the pedal shown, Problem 1.24 determine (a) the diameter of the pin at C for which the average shearing stress in the pin MPa, (b) the corresponding bearing stress in the pedal at C, (c) the corresponding bearing stress in the each support bracket at C. 75 mm 300 mm A B Draw free body FAB P diagram of ACD. 125 mm Since ACD is a P C 3- Force D the reaction at C C is directed toward point E, the intersection of the lines of action of the other two forces. 5 mm From geometry, + 1252 = 325 mm C P = C = N (a) = Apin (b) dt = Pa (9x10-3) 1950 (c) = = Pa 2dt</p><p>Problem 1.25 1.25 A 12-mm-diameter steel rod AB is fitted to a round hole near end C of the wooden member CD. For the loading shown, determine (a) the max- imum average normal stress in the wood, (b) the distance b for which the av- 18 mm erage shearing stress is 620 kPa on the surfaces indicated by the dashed lines, 2.25 (c) the average bearing stress on the wood. A 75 mm D kN (a) Maximum average normal stress in the wood. B C Anet = P=4.50 KN N 3.97x10' Pa 3.97 MPa (b) P = P P = = m A 2bt b 202 mm (c) = dt P = = Pa 20.8 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.26 1.26 Two identical linkage-and-hydraulic-cylinder systems control the position of the forks of a fork-lift truck. The load supported by the one system shown is 6 kN. Knowing that the thickness of member BD is 16 mm, deter- mine (a) the average shearing stress in the 12-mm-diameter pin at B, (b) the bearing stress at B in member BD. A B 300 mm G Co 300 mm By Use one as a free body. D E 6 kN 380 mm Bx = = 400 mm 400 mm 500 mm E 6 KN - = = 7.81 KN (a) Shearing stress in pin at B. -6 2 = m Apin = = (b) Bearing stress at B. 6 = B = = dt 40.6MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.27 1.27 For the assembly and loading of Prob. 1.7, determine (a) the average shearing stress in the pin at B, (b) the average bearing stress at B in member BD, (c) the average bearing stress at B in member ABC, knowing that this member has a 10 X 50- mm uniform rectangular cross section. 0.4 m 1.7 Each of the four vertical links has an 8 X 36-mm uniform rectangular cross C section and each of the four pins has a 16-mm diameter. Determine the maximum 0.25 m value of the average normal stress in the links connecting (a) points B and D, (b) 0.2 points C and E. B Use bar ABC as a free body. 20 kN 0.025 0.040 A € A B FBD C FCE = O: = N (a) Shear pin at B. for double shear, where = (b) link BD. = dt = = MPa (c) Bearing in ABC at = dt = (0.016)(0.010) = = = MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem1.28 1.28 Link AB, of width b = 50 mm and thickness 6 mm, is used to support the end of a horizontal beam. Knowing that the average normal stress in the link is -140 MPa, and that the average shearing stress in each of the two pins is MPa. determine (a) the diameter d of the pins, (b) the average bearing stress in the link. Rod AB is in compression. A= bt where b=50mm and 6 (0.050)(0.006) B = N For the pin, and P Ap = = (a) Diameter d. = = d mm (b) = P = 42x103 = Pa MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.29 1.29 The 5.6-kN load P is supported by two wooden members of uni- form cross section that are joined by the simple glued scarf splice shown. De- termine the normal and shearing stresses in the glued splice. P 125 mm 6227N 75 mm = 9.375 = Psin20 = 2A. MPa P' Problem 1.30 1.30 Two wooden members of uniform cross section are joined by the simple scarf splice shown. Knowing that the maximum allowable tensile stress in the glued splice is 525 kPa, determine (a) the largest load P that can be P safely supported, (b) the corresponding tensile stress in the splive. 125 mm 75 mm 9.375 in 2 6 = Ao (a) P = = 6562N cus2 30° KN P' (b) Psin20 = MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.31 1.31 Two wooden members of uniform rectangular cross section are joined by the simple glued scarf splice shown. Knowing that P=11 kN, determine the normal and P' shearing stresses in the glued splice. 150 mm P N 75 mm mm = = (1) = Pa 489 Psin20 = Pa 489 KPA Problem 1.32 1.32 Two wooden members of uniform rectangular cross section are joined by the simple glued scarf splice shown. Knowing that the maximum allowable tensile stress P' in the glued splice is 560 kPa, determine (a) the largest load P that can be safely 150 mm applied, (b) the corresponding shearing stress in the splice. = P = 75 mm = Pa Ao 5A. (a) = N KN (b) = A = 560x103 Pa KPa</p><p>Problem 1.33 1.33 A centric load P is applied to the granite block shown. Knowing that the resulting maximum value of the shearing stress in the block is 17 MPa, determine (a) the magnitude of P, (b) the orientation of the surface on which the maximum shearing stress occurs, (c) the normal stress exerted on the sur- P face, (d) the maximum value of the normal stress in the block. Ao 17 MPa for plane of (a) 2A. = 765 KN 150 mm 150 mm (b) sin (c) A. 2(0.0225) =-17 MPa (d) = As 0.0225 Problem 1.34 1.34 A 960-kN load P is applied to the granite block shown. Determine the resulting maximum value of (a) the normal stress, (b) the shearing stress. Spec- ify the orientation of the plane on which each of these maximum values occurs. P 6 = P - Ao (a) max tensile stress If at = 90° compressive stress = 42.7 MPa 150 mm at 150 mm (b) Image = P = 21.3 MPa at = 45° Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.35 1.35 A steel pipe of 400-mm outer diameter is fabricated from 10-mm-thick plate by welding along a helix that forms an angle of 20° with a plane perpendicular to the axis of the pipe. Knowing that the maximum allowable normal and shearing stresses P in the directions respectively normal and tangential to the weld are = 60 MPa and = 36 MPa, determine the magnitude P of the largest axial force that can be applied to the pipe. 10 mm m Weld = - m = 12.25 = Based on MPa: A. P P= = = 3 N Based on 121=30 = MPa sin 20 = = 1372x103 N sin 20 Smaller value is the allowable value of P. P = 833 KN Problem 1.36 1.36 A steel pipe of 400-mm outer diameter is fabricated from 10-mm-thick plate by welding along a helix that forms an angle of 20° with a plane perpendicular to the axis of the pipe. Knowing that a 300-kN axial force P is applied to the pipe, P determine the normal and shearing stresses in directions respectively normal and tangential to the weld. 10 mm - m Weld Ao = - 20° = O 20° Ao Pa P sin 20 = sin 7.87 MPa</p><p>Problem 1.37 1.37 A steel loop ABCD of length 1.2 m and of 10-mm diameter is placed as shown around a 24-mm-diameter aluminum rod AC. Cables BE and DF, each of 12-mm diameter, are used to apply the load Knowing that the ultimate strength of the steel used for the loop and the cables is 480 MPa, determine the largest load Q that can be 240 mm 240 mm applied if an overall factor of safety of 3 is desired. E 180 mm 24 mm Q C Using joint B asafree body 180 mm and considering symmetry, 10 mm = FAB FAB D 12 mm F = Q' Using joint A as a free body FAR and considering symmetry, FAB - FAC - = Q - FAC : Q = Based on strength of cable Qu = = = N Based on strength of steel loop. Qu = = (0.010)2 = N Based on strength of rod AC. = = N Actual ultimate load Qu is the smallest. 45. N Allowable load Q = = N Q=15.08 KN Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.38 1.38 Member which is supported by a pin and bracket at and a cable BD, was designed to support the 16-kN load P as shown. Knowing that the ultimate load for cable BD is 100 kN, determine the factor of safety with respect to cable failure 40° P D A B P Use member ABC as a A 0.6 m free body, and note that member BD is a C two-force - member. 0.8 0.4 m DEM, = O: 40° + (P 30° = 1.30493 - 0.71962 FBO = = 1.81335 P = (1.81335) = 3 N N F.S. 100x103 = F.S. = 3.45 FBD Problem 1.39 1.39 Knowing that the ultimate load for cable BD is 100 kN and that a factor of safety of 3.2 with respect to cable failure is required, determine the magnitude of the D largest force P which can be safely applied as shown to member ABC. 40° P A B 30° Use member ABC as a A free body, and note 0.6 m that member BD is a B C two-force - mem ber. = 0.8 in 0.4 m - - = 1.30493 0.71962 FBD = 0.55404 FBO value of F.S. = 100 3.2 = 3. 125 KN Pall = Pall= 1.732 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.40 1.40 The horizontal link BC is 6 mm thick, has a width W = 30 mm, and is made of a steel with a 450-MPa ultimate strength in tension. What P is the factor of safety if the structure shown is designed to support a load P = 40 kN? A w B 150 mm KN FBC 300 mm D ABC = D Dx Dy = = 2034 Problem 1.41 1.41 The horizontal link BC is 6 mm thick and is made of a steel with a 450-MPa ultimate strength in tension. What should be the width W of the link if the structure shown is to be designed to support a load P = 32 kN with a P factor of safety equal to 3? A to B (0.3cos 150 mm FAB = 27.7 KN C = 300 mm AAB tw F.S. = Dx m Dy mm Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.42 1.42 Link AB is to be made of a steel for which the ultimate normal stress is 450 MPa. Determine the cross-sectional area for AB for which the factor of safety will be 3.50. Assume that the reinforced around the pins at and B. 8 kN/m 35° 9 E FAB P B C D 20 Dx 0.4 in 0.4 m 0.4 m - +(0.2)(9.6) QV Dy KN = N 5AB FAB AAB I, F.S. = 168. AAC 168. mm2 Proprietary Material. 2009 The Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.43 1.43 The two wooden members shown, which support a 16-kN load. are joined by plywood splices fully glued on the surfaces in contact. The ultimate shearing stress in the glue is 2.5 MPa and the clearance between the members is 6 Determine the required length L of each splice if a factor of safety of 2.75 is to be achieved. 16 125 mm L There are 4 separate areas of glue. Each area must transmit 8 KN 6 of shear load. P= 8 KN = N Required ultimate load. = = N Required length of each glue area. TUA = 22x103 = m -3 Length of splice: L= 2l+c = + 0.006 = 0.1468 x10 m L= 146.8 mm Problem 1.44 1.44 For the joint and loading of Prob. 1.43, determine the factor of safety. knowing that the length of each splice is L 180 mm. 1.43 The two wooden members shown, which support a 16-kN load, are joined by plywood splices fully glued on the surfaces in contact. The ultimate shearing stress in 16 kN 125 mm the glue is 2.5 MPa and the clearance between the members is 6 Determine the required length L of each splice if a factor of safety of 2.75 is to be achieved. L There are 4 separate areas of glue. 6 mm Each glue area must transmit 8 KN of shear load. 8 KN = N Length of where = length of glue and C = clearance. = = 0.087 m Area of glue. A= (0.087)(0.125) = m Ulimate load. = N Factor of safety. F.S. = F.S. = 3.40</p><p>Problem 1.45 1.45 Three 18-mm-diameter steel bolts are to be used to attach the steel plate shown to a wooden beam. Knowing that the plate will support a 110-kN load and that the ultimate shearing stress for the steel used is 360 MPa, determine the factor of safety for this design. For each bolt, A = = = = N 110kN For the three bolts, = N Factor of safety. F.S. = P = F.S.=2.50 Problem 1.46 1.46 Three steel bolts are to be used to attach the steel plate shown to a wooden beam. Knowing that the plate will support a 110 load, that the ultimate shearing stress for the steel used is 360 MPa, and that a factor of safety of 3.35 is desired, determine the required diameter of the bolts. For each bolt, KN Required Pu = (F.S.)P = (3.35)(36.667) = 122.83 Pu A = Pu = 110 kN = -3 m (360x 100) d 20.8 mm Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course préparation. A student using this manual is using it without permission.</p><p>1.47 A load P is supported as shown by a steel pin that has been inserted in a short Problem 1.47 wooden member hanging from the ceiling. The ultimate strength of the wood used is 60 MPa in tension and 7.5 MPa in shear, while the ultimate strength of the steel is 145 MPa in shear. Knowing that b = 40 mm, 55 mm, and d 12 mm, determine the load P if an overall factor of safety of 3.2 is desired. 1.48 For the support of Prob. 1.47, knowing that the diameter of the pin is d 16 mm and that the magnitude of the load is P = 20 kN, determine (a) the factor of safety for the pin, (b) the required values of b and if the factor of safety for the wooden members is the same as that found in part a for the pin. d P = 20 KN = N 2 P (a) A = = P Double shear 40 mm = = N F.S. = Pu = = 2.92 (b) Tension in wood = N for same F.S. = A Pu = w(b-d) Pu where mm = 0.040 m b = = 0.016 + = m mm in wood Pu = N for same F.S. Double shear; each area is WC Pu Pu Pu 58.336x103 = = 97.2 m 97.2 mm Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.48 1.48 A load P is supported as shown by a steel pin that has been inserted in a short wooden member hanging from the ceiling. The ultimate strength of the wood used is 60 MPa in tension and 7.5 MPa in shear, while the ultimate strength of the steel is 145 MPa in shear. Knowing that b = 40 mm, = 55 mm, and 12 mm, determine the load P if an overall factor of safety of 3.2 is desired. Based on double shear in pin P Pu = = = = N 40 mm Based on tension in wood Pu = - N Based on double shear in the wood Pu = = 2 = = N Use smallest Pu = 32.8 x103 N Allowable F.S. = N 3.2 10.25 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.49 1.49 Each of the two vertical links CF connecting the two horizontal members AD and EG has a 10 40-mm uniform rectangular cross section and is made of a steel with an ultimate strength in tension of 400 MPa, while each of the pins at C and F has a 20-mm diameter and is made of a steel with an ultimate strength in shear of 150 MPa. Determine the overall factor of safety for the links CF and the pins connecting 250 mm them to the horizontal members. 400 mm A 250 mm B Use member EFG as free body. C D FBE FeF E F F 0.40 0.25 24 kN DEME = 0.40 FCF = N Based on tension in links CF A = = = (one link) = N Based on double shear in pins A = = (0.020)2 = 314.16 = N Actual is smaller value, i.e. = N Factor of safety F.S. = = = 2.42 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.50 1.50 Solve Prob. 1.49, assuming that the pins at C and F have been replaced by pins with a 30 mm diameter. 1.49 Each of the two vertical links CF connecting the two horizontal members AD and EG has a uniform rectangular cross section 10 mm thick and 40 mm wide, and is made of a steel with an ultimate strength in tension of 400 MPa. The pins at 250 mm each have a 20 mm diameter and are made of a steel with an ultimate strength in shear of 150 MPa. Determine the overall factor of safety for the links CF and the pins 400 mm connecting them to the horizontal members. A 250 mm B Use member EFG as free body. C Fee D E E G 0.4m 0.25m F 24 KN 24 kN 0.4 = Failure by tension in links CF. (2 links) Net section area for link: = =160 KN Failure by double shear in pins. = 2A = (150x106) Actual ultimate load is the smaller Factor of safety: F.S. = 2.42 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.51 1.51 Each of the steel links AB and CD is connected to a support and to member BCE by 25-mm-diameter steel pins acting in single shear. Knowing that the ultimate 50 mm shearing stress is 210 MPa for the steel used in the pins and that the ultimate normal D stress is 490 MPa for the steel used in the links, determine the allowable load P if an P overall factor of safety of 3.0 is desired. (Note that the links are not reinforced 12 mm B around the pin holes.) C E A Use member BCE as free body. = 0.3 = 300 mm P B C E FAB Both links have the same area, pin diameter and material, There they have the same ultimate load. Failure by pin in single shear. Fu = = = 103.09 Failure by tension in link. Fu = = Ultimate load for link and pin is the smaller. KN Allow able values of and FAB. 34.36 KN Allowable load for structure is the smaller of Full P KN Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means. without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.52 1.52 An alternative design is being considered to support member BCE of Prob. 1.51, in which link CD will be replaced by two links, each of 6x50-mm cross section, causing the pins at Cand D to be in double Assuming that all other 50 mm specifications remain unchanged, determine the allowable load P if an overall factor of safety of 3.0 is desired. D P 1.51 Each of the steel links AB and CD is connected to a support and to member 12 B BCE by 25-mm-diameter steel pins acting in single shear. Knowing that the ultimate shearing stress is 210 MPa for the steel used in the pins and that the C E ultimate normal stress is 490 MPa for the steel used in the links, determine the allowable load P if an overall factor of safety of 3.0 is desired. (Note that the links are not reinforced around the pin holes.) 450 min 300 mm Use member as free body. P 0.3 B C E Me = 0.3 FAB-0.45 P = FA AB Area of all pins: = Net section area of link AB: Anet= (b-d) = Net section area of the 2 links CD is the same. Failpre by pins A and B in single shear. = (210x106) 103.09 KN Failure by tension in link AB. = = 147 KN Ultimate load for link and pins AB is the = 103.09 KH Corresponding ultimate load, Pu = = 68.73 KN Failure by pins C and in double shear. = KN Failure by tension in links CD. = (490x106) (3x10-4) = 147 KN Ultimate loud for links and pins CD is the = 147 Corresponding ultimate load: KN Actual ultimate load is the smaller. 58.8 KN Allowable load P: 3.0</p><p>Problem 1.53 1.53 In the steel structure shown, a 6-mm-diameter pin is used at C and 10-mm- diameter pins are used at B and D. The ultimate shearing stress is 150 MPa at all connections, and the ultimate normal stress is 400 MPa in-link Knowing that a factor of safety of 3.0 is desired, determine the largest load P that can be applied at A. Note that link BD is not reinforced around the pin holes. D Use free body ABC. Front view 6 mm 18 mm 0.280 0.120 FBD = (1) A B C Side view 160 mm 120 mm P C = A B Top view C C (2) Tension on net section of link BD. P C = Anet = F.S. x103 N Shear in pins at B and FBD = = F.S. = N value of FBD is N. From (1) = N Shear in pin at C C = F.S. = N From (2) P = = N Smaller value of P is allowable value. N P= 1.683 KN</p><p>Problem 1.54 1.54 Solve Prob. 1.53, assuming that the structure has been redesigned to use 12- mm-diameter pins at B and D and no other change has been made. 1.53 In the steel structure shown, a 6-mm-diameter pin is used at C and 10-mm- diameter pins are used at B and D. The ultimate shearing stress is 150 MPa at all connections, and the ultimate normal stress is 400 MPa in link BD. Knowing that a factor of safety of 3.0 is desired, determine the largest load P that can be applied at A. Note that link BD is not reinforced around the pin holes. D Front view Use free body ABC. 18mm 6 mm A (1) B C 160 mm 120 mm Side view P - 0.120 C = A (2) B Top view C FBO Tension on net section of link BD. = = F.S. V P C = N Shear in pins at B and D. FBD = F.S. To = N Smaller value of FBD is N. From N Shear in pin at C. C = To = N From N Smaller value of P is the allowable value. N P= 2.06 KN</p><p>Problem 1.55 1.55 In the structure shown, an 8-mm-diameter pin is used at A, and 12-mm-diameter pins are used at B and D. Knowing that the ultimate shearing stress is 100 MPa at all connections and that the ultimate normal stress is 250 MPa in each of the two links joining B and D, determine the allowable load P if an overall factor of safety of 3.0 is desired. Top view 180 mm 12 mm 8 T : Use ABC as free body. B A B B A C 0.20 0.18 B P FA FBO 20 mm 8 mm 8 mm DEMB = FA - D D 12 mm Front view Side view 0.20 FBD 0.38 P = a Based on double shear in pin A. A = = = 3.0 = 3 N FA N Based on double in pins at B and D. = = = N FBD = 3.97 N Based on compression in links BD. For one link A = = 26.7 N FBD = 14.04 103 N Allowable value of P is smallest. : P= N P= 3.72 KN</p><p>Problem 1.56 1.56 In an alternative design for the structure of Prob. 1.55, a pin of 10-mm-diameter is to be used at A. Assuming that all other specifications remain unchanged, determine the allowable load P if an overall factor of safety of 3.0 is desired 1.55 In the structure shown, an 8-mm-diameter pin is used at A, and 12-mm-diameter pins are used at B and D. Knowing that the ultimate shearing stress is 100 MPa at all connections and that the ultimate normal stress is 250 MPa in each of the two links joining B and D, determine the allowable load P if an overall factor of safety of 3.0 is Top view desired. 200 mm 180 mm 12 mm 8 B C Statics : Use ABC as free body. A B B A C B 0.20 0.18 P 20 P 8 FA mm 8 mm D D = 0.20 FA P = 12 mm Front view Side view 0.20 Based on double shear in pin A. FBD A = = = = N 3.0 FA = N Based on double shear in pins at B and D. = 3 = = N FBD 3.97 N Based on compression in links BD. For one link A = = = 3.0 = 26.7 N FBD = 14.04 103 N Allowable value of P is smallest. : P= N</p><p>Problem 1.57 *1.57 A 40-kg platform is attached to the end B of a 50-kg wooden beam AB, which is supported as shown by a pin at A and by steel rod BC with a 12-kN ultimate load. (a) Using the Load and Resistance Factor Design method with a C resistance factor 0.90 and load factors = 1.25 and = 1.6, determine the largest load that can be safely placed on the platform. (b) What is the corresponding conventional factor of safety for rod BC? 1.8 m A B 4 2.4 m Ax 3 5 Ay W2 W, DEM, A = 2.4 W, - 1.2 W2 For dead loading, W, = (40)(9.81) = 392.4 N W2 = (50)(9.81) = 490.5N Po = = 1.0628 N For live loading, mg W2 = 0 mg from which PL Design criterion. + = Q Pu - = = 1.6 N (a) Allowable load. m = kg Conventional safety. + If N (b) F.S. = = P 6.983x103 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.58 *1.58 The Load and Resistance Factor Design method is to be used to select the two cables that will raise and lower a platform supporting two win- P P dow washers. The platform weighs 72 kg and each of the window washers is assumed to weigh 88 kg with equipment. Since these workers are free to move on the platform, 75% of their total weight and the weight of their equipment will be used as the design live load of each cable. (a) Assuming a resistance factor = 0.85 and load factors 1.2 and = determine the re- quired minimum ultimate load of one cable. (h) What is the conventional fac- tor of safety for the selected cables? + = Pu = + = 0.85 = 283.76 kg = 2.78 KN Conventional factor of safety = = 1x72 + 0.75 = 168kg = F.S. = Pu = 2.784 P 1.648 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.59 1.59 Link BD consists of a single bar 24 mm wide and 12 mm thick. Knowing that each pin has a 9 mm diameter, determine the maximum value of the average normal stress in link BD if (a) 0 = 0, (b) 0 = 90°. 16 C 150 mm Use bar ABC B 300 mm as free body. B A FBD A Ax Ay (a) EM, = (0.45sin ) FBD = KN (tension) Area for tension loading: A=(b-d)t = (24-9)(12)= 180 mm2 Stress 6 MPa (b) +) = FBD FBO = - 24 KN i.e. compression. Area For compression loading: = Stress : KN Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced. or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.60 1.60 Two horizontal 20 kN forces are applied to pin B of the assembly shown. Knowing that a pin of 20 mm diameter is used at each connection, de- 12 mm termine the maximum value of the average normal stress (a) in link AB, (b) in link BC. 45 mm 20 Use joint B as free body 12 mm A 60° 45 mm 40 KN 95° FAB FBC C FAB 60° 450 40 Law of Sines Force triangle FAB = Fee 40 = sin 45 sin 60° sin FAB = 28.4 KN FBC = 34.8 KN Link AB is a tension member Minimum section at pin Anet = = -6 2 (a) Stress in AB GAB = FAB = = Link BC is a compression member Cross sectional area is = (b) Stress in BC = = 540x10-6 34.8 = - 64.4 MPa Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced. or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.61 1.61 For the assembly and loading of Prob, 1.60, determine (a) the av- erage shearing stress in the pin at C, (b) the average bearing stress at C in mem- 12 mm ber BC, (c) the average bearing stress at B in member 1.60 Two horizontal 20-kN forces are applied to pin B of the assembly shown. Knowing that a pin of 20-mm diameter is used at each connection, de- termine the maximum value of the average normal stress (a) in link AB, (b) in link BC. 45 min 20 kN 20 kN 12 mm Use joint B as free body. A 60° 45° 45 mm 40 KN 95 AB C FBC 450 40 KN Force triangle Law of Sines FAB sin 450 sin 60° = FBC = 34.77 KN (a) Shearing stress in pin at C. = = 314.16 mm2 MPa (b) Bearing stress at C in member BC. - = A= td = mm2 =144.875 (c) Bearing stress at B in member BC. =2td = 480 mm2 6b = Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.62 1.62 Two wooden planks, each 22 mm thick and 160 mm wide, are joined by the glued mortise joint shown. Knowing that the joint will fail when the average shearing stress in the glue reaches kPa, determine the smallest allowable length d of the cuts if the joint is to withstand an axial load of magnitude P = 7.6 kN. d Seven surfaces carry the total P' P 160 mm 7.6 = 20 mm Let 22 Each glue area is 2 = 7A P A = P = = A = 22 60.2 d= = 60.2 Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.63 1.63 The hydraulic cylinder CF, which partially controls the position of rod DE, has been locked in the position shown. Member BD is 15 mm thick and is connected to the vertical rod by a 9-mm-diameter bolt. Knowing that P = 2 kN and 0 = determine (a) the average shearing stress in the bolt, (b) the bearing stress at C in 100 mm 175 mm member BD. D 0 B C 20° Use member BCD as a free body, and E note that AB is a two force member. 200 mm P A F Cx (2 45 mm Cy Length of member 200 + 452 205 FAB 205 mm DEM = (200 205 FAB)(100 sin 20°) - (175 = 84.16.96 (4-1424) Cx=0.3917 KN (4.1424) - Cy=5.9732 Reaction at C: 5.9860 (a) Shearing stress in bolt shear). = = = Pa (b) Bearing stress at C in member = = (0.009)(0.015) = Pa = Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.64 1.64 The hydraulic cylinder CF, which partially controls the position of rod DE, has been locked in the position shown. Link AB has a uniform rectangular cross section of 12 25 mm and is connected at to member BD by an 8-mm-diameter pin. Knowing that the maximum allowable average shearing stress in the pin is 140 MPa, 100 mm 175 mm determine (a) the largest force P which may be applied at E when 0 = 60°, (b) the D corresponding bearing stress at B in link AB, (c) the corresponding maximum value of the normal stress in link AB. B C 20° E Use member BCD as a free body, and 200 mm P note that AB is a two force member. A 60 F 45 mm Cx Length of member AB. Cy 200 205 FAB = O: 205 - 205 = 84. 1696 FAB - 172.3414 P = 2.0475 P (a) Allowable load P. Pin at A is in single shear. = = Pa P (b) Bearing stress at B in link AB. t= 12 mm = (0.008)(0.012) = = N = (c) Maximum normal stress in link AB. b=25 mm, t=0.012 mm = - = FAB = = Pa</p><p>Problem 1.65 1.65 Two wooden members of 70 110-mm uniform rectangular cross section are joined by the simple glued scarf splice shown. Knowing that the maximum allowable shearing stress in the glued splice is determine the largest axial load 110 can be safely applied. P' 70 mm P m2 = Ao P sin = 3 N P=11.98 KN Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.66 1.66 The 900-kg load may be moved along the beam BD to any posi- tion between stops at E and F. Knowing that MPa for the steel used in rods AB and CD, determine where the stops should be placed if the permit- 1.5 in ted motion of the load is to be as large as possible. A C 12 mm 16 mm diameter diameter Permitted member F B D KN x CD : = = (42x10) 8.44 KN FAB Use member BEFD as a free 1.5 m 900 kg = 8.829 KN B D = P= 900kg - -(1.5) FAB + 1.5 FAB = 8.829x103 = 0.807 0.693 in = 1.5 = Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p><p>Problem 1.67 1.67 A steel plate 10 mm thick is embedded in a horizontal concrete slab and is used to anchor a high-strength vertical cable as shown. The diameter of the hole in the plate is 24 mm, the ultimate strength of the steel used is 250 MPa, and the ultimate P bonding stress between plate and concrete is 2.1 MPa. Knowing that a factor of safety of 3.60 is desired when P = 18 kN, determine (a) the required width a of the plate, (b) the minimum depth b to which a plate of that width should be embedded in the concrete slab. (Neglect the normal stresses between the concrete and the lower end of the plate.) 10 mm 18 KN (a) Based on tension in the plate. 24 mm P solving for a, a= d+ (F.S.)P 0.024+ a= 0.04992 m mm (b) Based plate and slab. A = perimeter depth = (2a+ 2t) b = Pa 2 To F.S. = Solving for b, = b= 0.25748 b=257 mm Proprietary Material. 2009 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced, or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. A student using this manual is using it without permission.</p>