Stirrups do not preventing inclined cracks from forming.

At a point subjected to plane stress, the stresses are σx = –15 ksi, σy = 15 ksi, and τxy = 5 ksi. Determine the angle θp corresponding to the orientation of the principal planes at the point.

Axial compression tends to _______ shear strength?

A 120-mm-long beam supports a load of P = 47 N at midspan. The cross section is rectangular with width b = 27 mm and height h = 60 mm. Determine the magnitude of the horizontal shear stress at the centroid of the cross section.

A rectangular beam with cross section b = 16 in., h = 22 in., and d = 19.5 in. supports a total factored uniform load of 3.80 kips/ft, including its own dead load. The beam is simply supported with a 19-ft span. It is reinforced with four No. 8 Grade 60 bars, two of which are cutoff between midspan and the support and two of which extend 10 in. past the centers of the supports. The concrete strength is 6,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups satisfying ACI 318-14 Sections 9.7.6.2.2 and 9.6.3.3. The strength of the four bars is φMn = 262.9 kip-ft, and the strength of the remaining two bars is φMn = 135.1 kip-ft. Determine the distance from the support to the theoretical cutoff point (i.e. disregard ACI 318-14 Section 9.7.3.3).

A rectangular beam has a cross section of b = 14 in., h = 22 in., and d = 19.5 in. It is reinforced with four No. 6 Grade 60 bars. The concrete strength is 5,500 psi (normal weight). The beam has Grade 60 No. 3 stirrups satisfying ACI 318-14 Sections 9.7.6.2.2 and 9.6.3.3. Determine the strength φMn for this beam.

Determine the transverse reinforcement index, Ktr, for a rectangular beam with b = 18 in. and d = 24 in., three galvanized No. 9 Grade 60 tension-reinforcement bars placed in the top of the beam, and No. 3 Grade 40 stirrups located every 12 in. along the span. Assume 4,000-psi lightweight concrete and a clear cover of 2 in.

Determine the size modification factor, ψs, for a rectangular beam with b = 18 in. and d = 20 in., three uncoated No. 8 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 3 Grade 60 stirrups located every 6 in. along the span. Assume 6,000-psi lightweight concrete and a clear cover of 1.5 in.

A rectangular beam with cross section b = 14 in., h = 26 in., and d = 23.5 in. supports a total factored uniform load of 1.80 kips/ft, including its own dead load. The beam is simply supported with a 19-ft span. It is reinforced with four No. 5 Grade 60 bars, two of which are cutoff between midspan and the support and two of which extend 10 in. past the centers of the supports. The concrete strength is 6,900 psi (normal weight). The beam has Grade 60 No. 3 stirrups satisfying ACI 318-14 Sections 9.7.6.2.2 and 9.6.3.3. The strength of the four bars is φMn = 128.6 kip-ft, and the strength of the remaining two bars is φMn = 64.93 kip-ft. Determine the distance from the support to the theoretical cutoff point (i.e. disregard ACI 318-14 Section 9.7.3.3).

Assuming Vs does not exceed 4sqrt(f’c)bwd, the maximum spacing for vertical stirrups in the following beam is _____. Let b1 = 21 in., b2 = 10 in., d = 39 in., h1 = 6 in., h2 = 29 in., h3 = 9 in., and t = 6 in. There are six No. 7 longitudinal tension bars and No. 4 stirrups at 9 in. o.c.