SU1300212A1 - Device for investigating bending moment influence lines in beams by kinematic method - Google Patents

Abstract

The invention relates to devices for studying the magnitude of the bending moment and can be used in the design of bridges, trusses and other structures. The purpose of the invention is to simplify the design of the device and increase its speed. The device includes a base 1, supports 2, 3-hour type indicators, a multi-span hinge beam 4, made of a composite of 5 main cantilever sections 6 connected by means of hinges and an additional suspension section 7 suspended from the consoles of adjacent main sections 6, a load unit. Sections 6 are made in the form of 2 double-console beam elements hinged on supports. The device is equipped with a cargo bracket for suspending the load unit in the span under study. The sections of the hinge beam have end sections formed with grooves and protrusions that fit into them, each pair of which is made with through coaxially horizontal holes for hinges in the form of removable studs. 2 Il. with (L of fig. 1

Description

25

113002

The invention relates to instruments for studying the magnitude of the bending moment in various cross sections of multi-span hinge beams and can be used in the design of 5 skeletons, roof frames and other structures.

The purpose of the invention is to simplify the design of the device and increase its speed.

Figure 1 shows the device, a general view; figure 2 - node 1 in figure 1.

The device includes a base 1, supports 2, 3-hour type indicators, multi-span hinge beam 4, an integral component of the main cantilever sections 6 connected by means of hinges 5 and an additional suspended section 7 suspended from the consoles of adjacent main sections 6, loading unit 8. Sections 6 are made in the form of 2 hinged beam elements hinged on supports 2.

The device is equipped with a cargo bracket 9 for suspending the load unit 8 to the console of the corresponding beam element 6 in the span under study (section A or B). Interconnected sections of the hinge beam have end sections formed with grooves 10 and protrusions 11 that enter them, each pair of which is made with through 35 coaxial horizontal holes for hinges in the form of removable studs 12. Removing one of the studs 12 and hanging on the bracket 9, a load is created relative to the remaining stud in the section under consideration (A or B), which causes the left and right sections 6 of the device to rotate relative to each other. Moving these sections results in movement of the nearby sections of the multi-span hinge beam 4. As a result, movement of individual beam elements is obtained, similar to the influence of the bending moment in the multiple span hinge beam.

thirty

.- 45

, 50

After the indicator measures 3 movements in predetermined cross sections from similar triangles, displacements in all necessary cross sections are easily determined. After that, this is the calculation of the magnitude of the exiting moment in the given cross sections25

002

five

35 thirty

45

50

55

22

It is produced by a known dependency.

M —Z: P; y + i: q, CO; + E M; where M is the bending moment in the given

section; Pj values lumped

external forces acting on the hinge beam;

Y; - the ordinates of displacement taken from the line under study are influenced by the corresponding weight; q; - values of the distributed load acting on the hinge beam; CD; - line area influenced by or under

appropriate distributed load; M-- values lumped

external moments acting on the hinge beam; tgoi; - the values of the tangent of the angle of inclination of the influence line in sections where external moments are applied.

Claims (1)

The use of the proposed device allows to simplify the design, improve speed, and improve consistency. Invention Formula A device for examining the lines of influence of a bending moment in beams by the kinematic method, including a base, supports, hour-type indicators, a multi-span hinge beam, filled as a composite of connected - by means of hinges of sections, and a load block, which is so that, in order to simplify the design of the device and improve its speed, the sections are made in the form of double-console beam elements hinged to the supports, and the device is equipped with a cargo bracket for suspending the load in unit to the console of the corresponding beam element in the span being studied and an additional section hinged to the consoles of adjacent main sections in the span being studied, while the interconnected sections of the hinge beam have end sections formed with grooves and protrusions into them, each connecting A pair of them is made with horizontal through-to-c about 1; Versions under the Sharfs in the form of removable studs. f1 W -. // Yg Compiled by V.Dankov Editor M.Petrova Tehred M.Hodanich Order P4 / 35 Circulation 760 Subscription VNIIPI USSR State Committee on affairs of inventions and opening 113035, Moscow, Zh-35, Raushsk nab., D. 4/5  Production 1podagrIficheskoe enterprise, Uzhgorod, Projecto st., 4 FIG. 2