Essentials in the theory of framed structures . at the base, plus horizontal component of the normal roof = horizontal reaction at base of leeward or right = distance from base of column to foot of = distance from base of column to point of contraflexure of windward = distance from base of column to point of contraflexure of leeward column. Suppose that H = 10,000 lb. for the structure, in whichI = 40 ft. and A = 21 ft. If the columns are pin-connected, thehorizontal reaction at the base of the leeward column is Hb = 10,000 X = 3,850 lb. If the colu
Essentials in the theory of framed structures . at the base, plus horizontal component of the normal roof = horizontal reaction at base of leeward or right = distance from base of column to foot of = distance from base of column to point of contraflexure of windward = distance from base of column to point of contraflexure of leeward column. Suppose that H = 10,000 lb. for the structure, in whichI = 40 ft. and A = 21 ft. If the columns are pin-connected, thehorizontal reaction at the base of the leeward column is Hb = 10,000 X = 3,850 lb. If the columns are fixed and rf = 15, then Hb = 10,000 X = 3,560 ; = 15 X = = 15 X = ft. The structure is statically determinate when one horizontalreaction and the points of contraflexure are known. I20 THEORY OF FRAMED STRUCTURES Chap. Ill The columns are seldom, if ever, built with pin connections;nor are they sufficiently anchored to the masonry to insure aperfectly rigid connection. The actual conditions existing. Fig. 85. in all mill-building bents are to be found between these twolimits. For example, in the structure before mentioned,where I = 40 ft. and h = 21 it., the horizontal reaction of theleeward column will be between and of the hori- Sec. II ROOF TRUSSES 121 zontal load. The point of contraflexure, or point of zeromoment, in the leeward column will be found between the baseof the column and the point of the distance to the foot ofthe knee-brace. A comparison of the data in columns 4 and 5of Table III indicates that , instead of , is themore reasonable estimate of the horizontal reaction of theleeward column; when the columns are considered partiallyfixed. The data given in columns 6 and 7 indicates that thepoint of contraflexure in each column may be taken at one-third b d
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectstructu, bookyear1922
