Tools › Civil and Geotechnical › Timber and Masonry

Timber and Masonry

2 tools in the Civil and Geotechnical area.

Timber Beam and Column

Allowable-stress design of a sawn-lumber or glulam beam and column by the Wood Handbook mechanics (USDA FPL-GTR-190 chapter 9) with the NDS adjustment-factor names: the reference design values F_b, F_v, F_c, F_c⊥, E and E_min are entered (the NDS Supplement tables are not shipped; the defaults are illustrative values of the order the Wood Handbook chapter 7 procedure gives for a Douglas-fir grade), each adjusted value F′ is printed with its factor product, the beam stability factor C_L and the column stability factor C_P come from Ylinen's column equation (Wood Handbook eq. 9-28) on F_bE = 1.20 E′_min/R_B² and F_cE = 0.822 E′_min/(l_e/d)², the simple-span moment, shear, reaction and deflection from closed forms superposed, bending, shear, bearing and deflection checked as plain ratios, and the column's combined bending and axial load by the interaction of buckling modes (eq. 9-35) with the eccentricity term. The pre-1991 NDS forms printed in the Forest Service Timber Bridges manual are shown beside the current ones. Default: a 4 × 12 on a 14 ft span under 200 lb/ft and a 6 × 6 column 10 ft long under 15 kip, USCS units.

1 worked example reproduced, listed on the tool page.

Masonry Wall and Pier

Allowable-stress (working-stress) design of concrete-masonry and clay-masonry elements following the public-domain Army TM 5-809-3 / NAVFAC DM-2.9 / AFM 88-3 Chap. 3, Masonry Structural Design for Buildings (1992), with the TMS 402 / ACI 530 forms cited where they differ. Seven elements under one select: an unreinforced wall under axial load and out-of-plane bending on the net section (f_a / F_a + f_b / F_b with F_a = 0.25 f′_m [1 − (h/140r)²] or the (70r/h)² form, the flexural-tension check against an entered allowable, the kern and the Euler load); a reinforced wall out of plane (the manual's moment diagram with the eccentric and lateral loads additive or opposing, the transformed cracked section k, j, M_rm, M_rs for the rectangular and the T-section, the stress-reduction factor R, the axial-bending unity equations for masonry and steel, out-of-plane shear); a shear wall or pier in plane (f_v = V/(td) against F_vm by M/(Vd), the shear-reinforcement allowable F_vs and area, flexure with the reinforcement at the end, the axial and overturning stresses, the unity equation and the pier rigidity); a lintel or beam (shear and moment integrated from the uniform, arching-triangle and spread concentrated loads, resisting moments, the cracked and effective moments of inertia, service deflection with the long-term factor, stirrups, bearing and lateral support); local bearing (0.25 f′_m on the full area, 0.30 f′_m on one third); anchor bolts (the ACI 530-88 masonry-cone and steel formulas behind the manual's Tables 5-12 to 5-14 with the shear edge-distance reduction and the interaction); and a column or pilaster (F_a = [0.18 f′_m + 0.65 p_g F_sc] R, cracked or uncracked flexural stress, the unity equation at the top and at mid-height). The manual's Tables 5-1, 5-2, 5-3 and 5-5 (unit dimensions, equivalent thickness, effective area, wall weight) fill the blanks. Every check prints the demand-to-capacity ratio and a margin. The default is the manual's wall design example 1: a 12 in CMU wall 24 ft high under 25 psf of wind and 1,500 lb/ft at e = t/2 with one #6 bar at 24 in, f′_m 1,350 lb/in².

1 worked example reproduced, listed on the tool page.

Other Civil and Geotechnical sections

Design Loads · Steel Design · Concrete Design · Foundations · Soils · Hydraulics · Surveying and Earthwork