JPS60174928A - Dynamic experimental apparatus of beam structure - Google Patents

Abstract

PURPOSE:To visually grasp the dynamic phenomenon of a multi-type beam structure and to make it possible to perform various experiments, by providing an experimental support table and three kinds of fixed, movable and elastic support fulcrum members. CONSTITUTION:A proper fulcrum member is selected from a fixed fulcrum member 8, a movable fulcrum member 9 and an elastic fulcrum member 10 on the tracks 3-5 of a support table 1 corresponding to experimental content and moved to be fixed to a desired position to be arranged while a proper beam 7 to be tested is selected and supported by the fulcrum member of which the position is determined. Subsequently, a state, such that load is applied to the beam 7 by a wt. 20 as concentration load, is developed and the dynamic phenomenon changed by said load is directly observed by eyesight to visually grasp the theory of the beam structure while a dial gauge 26 is moved to the longitudinal direction of the beam 7 to be tested along the track 5 to measure the distortion amount or fulcrum strain of said beam 7 at a desired place and, further, a strain gauge is adhered to perform the measurement of flexural strain.

Description

DETAILED DESCRIPTION OF THE INVENTION There are many types of beam structures as shown in FIGS. In other words, these have a fixed fulcrum A, a fixed movable fulcrum opening, a horizontally movable fulcrum opening, and an elastic fulcrum. A simple beam supported by a fulcrum opening, b has one end supported by a stationary movable fulcrum opening, and the middle of the beam is a horizontal movable fulcrum ν.
C is a beam with one end supported by a fixed movable fulcrum, C is a beam with both ends supported by a stationary movable fulcrum P1 and a horizontal movable fulcrum mouth, and d is a beam supported at one end by a fixed movable fulcrum mouth, and the other end and the middle of the beam are supported by a horizontal movable fulcrum. A cantilever beam with only one end as a fixed fulcrum A, where one end is fixed and the other end is movable, g is a beam with one end fixed and the other end movable, and h is a two-span continuous beam with one end fixed and the other end movable. j is an elastic beam in which the movable fulcrum opening in a was changed to an elastic fulcrum, and k
Below are examples of elastic beams using elastic fulcrums.

The present invention forms such multi-type beam structures individually as models to directly visually observe the mechanical phenomena of each beam structure, and also to determine the amount of beam deflection, deflection angle, degree of bending stress, fulcrum reaction force,
A general-purpose experimental device that can easily conduct experiments such as influence lines, Young's modulus, bending moment diagrams, shear force diagrams, etc., and can be used for training on beam structures in civil engineering, architecture, and machinery.
- An experimental support that can be placed horizontally on the floor, a fixed support that can be moved along the horizontal support and fixed at a desired position, and an elastic support that can be used as a movable support. three types of fulcrum members for use, a test beam of a predetermined size that is installed on a support stand by selectively using these fulcrum members, and is supported by this to form a span, and a concentrated load on the test beam. A block-type weight for partially uniformly distributed loads, a roller chain of a predetermined length for uniformly distributed loads, and a test beam with a span that moves along the length of the test beam for a predetermined load. It consists of an appropriate number of dial gauges that are stopped at a certain position so that the measuring probe comes into contact with a test beam and a fulcrum member.

Embodiments of the present invention will be described with reference to the drawings.

In the drawing, (1) is a support stand for the experimental equipment installed on the floor.
A height adjustment mechanism (2) is provided at the bottom of the leg piece, and by adjusting the height adjustment mechanism (2), the upper surface of the support base (1) is always maintained horizontally at a predetermined height, and the upper surface of the support base (1) There is a trajectory (3) for moving the fulcrum member, which will be described later, with an interval in the front and rear.
(4) A track (5) for moving a dial gauge, which will be described later, was provided parallel to the track (5), and a length scale (6) was provided on each track.

A variety of test beams (7) were prepared so that the length, width, and thickness could be applied to the experimental content, and the materials were made of metal, wood, synthetic resin, and other materials. No. 178! As shown in J, the fulcrum member is provided with a mounting hole (7a) for fastening at the appropriate location, and a bent part (7b) with a hinge is provided in the middle as shown in Fig. 18.
A gel bar beam type specimen having 5= is also prepared.

Three types of beams are used for the test: those that support the force in a fixed manner, those that support the force movably, and those that support the force elastically.

The fixed fulcrum member (8) is fixed by clamping the beam (7) between the receiving member (8a) and the suppressing member (8b) as shown in FIGS. 4 and 5, and the movable fulcrum member is fixed as shown in FIG. 6. As shown in Fig. 7 and Fig. 8, a strip (
9b) is rotatably mounted on a shaft, and the beam (7) is fastened to the strip (9b) with a screw (9C), so that the shaft piece (9b) can rotate in a fixed position. (9) and a beam (
A thin piece (9b) whose force is connected with a screw can be rotated within the elongated hole (9d) of the bearing member (9a) and made horizontal movement possible (
9), and an elastic fulcrum member (Fig. 9 and 10).
As shown in the figure, an elastic spring (10a)'ic is applied below the movable fulcrum member (9).

And these three types of branch members (81(9) Ql are
As shown in FIGS. 4 to 10, the pressing member (8b) and the bearing member (9a) are used by being removably connected to the fulcrum mounting piece aυ with a locking screw, and the fulcrum mounting piece (lυ is installed so that it can be moved up and down by inserting it into the base cylinder α9 that is integrated with the shaft member a3 board I that is attached to the lower surface, and the fixed fulcrum member (8) and the movable fulcrum member (9) (9) are attached to the fulcrum. Two chain parts (16a) (1
6b) '51: M combination L Te configuration bottom telescopic cylinder (le
vi- The height of the fulcrum member (8) (9) (9) connected to the mounting piece αυ can be adjusted by interposing the elastic fulcrum member (8) (9) (9) by adjusting the elasticity of the elastic tube (instead of IQ). The spring (10a) is interposed to allow elasticity in the vertical direction, and each fulcrum member (8) <93
(1 (10) Attach the holding plate αη along the bottom surface of the board α4 with a set screw OFj, and form a track (3) (4) on the top of the support base (1) with the board α4 and the holding plate (1?) *By holding the board (14) and the holding plate (L7) 1 in the lengthwise direction of the track, and tightening the set screw QB at an arbitrary position.
The fulcrum position for the beam (7) can be arbitrarily set so that it can be fixed to the track.

In addition, by suspending a weight from the hook piece (11) provided at the lower end of each point member (8) (9) of Ql (13), it is possible to prevent the fulcrum member from flying upward during the experimental operation. Make sure not to.

A beam supported on a fulcrum member (8) (9) α to form a span (the following three types of load application means were used. Namely, a predetermined weight as shown in Fig. 11 for concentrated load) For a partially uniformly distributed load, a large number of block-type weights Qυ of a predetermined weight as shown in Fig. 12, and for a uniformly distributed load, a key ÷; is @141ffl.
As shown in the figure, a four-wire chain (2) of a predetermined length or a plurality of strips connected in a plane is used.

In addition, for the weight (to), attach the hook fR (c) shown in Fig. 16 to the beam (7) with a span formed as shown in Fig. 2.
It is used by supporting it on a weight holder suspended from this.

In addition, a block-type weight (2fJ is a K-beam (as shown in Figure 13) that is placed adjacent to the sumo wrestler over a predetermined length, and in this case, the deflection of the beam (7) causes friction between the 5I and the 14-beams in contact with each other. It is desirable to have a tapered surface on the negative side or both sides of the weight QI) so as not to cause restraint due to Glue this to the appropriate length (7)
When multiple strips are stacked, as shown in Figure 15, a membrane material (
c) It is desirable to ensure that the 4-rings (23) overlap vertically so that the load is distributed evenly in the length direction. Make it possible to decompose it into lengths i
This is a preview type weight (like 21j, it can also be used for partially uniformly distributed loads. The dial gauge (to) for measuring various mechanical values is attached to the track (5) on the support base (1). The dial gauge ■ is attached to the horizontal beam (force A plurality of measuring points are provided in the length direction, and the contact piece (7) is fixed to the upper surface of the beam (7) as shown in Figure 6, or to each fulcrum member (8) (9) H as shown in Figure 4. For example, a beam (for measuring the amount of deflection of force or fulcrum reaction force, etc.) is placed in contact with 32 surfaces, and its height and longitudinal position can be adjusted freely.

The present invention, which consists of the above-mentioned components, has tracks (3) (4) (5) on a support base (1) as shown in FIGS. 1 to 3.
), the fixed fulcrum member (8) and the movable fulcrum member (9)
+9) Also, the elastic fulcrum member Qlt - Select an appropriate one according to the content of the experiment, move and fix it to the desired position, and select an appropriate fulcrum member for the specimen beam (7) and position it as the fulcrum. The fixed fulcrum member (8) is supported by the member, and the beam (7) is clamped and fixed between the receiving member (8a) and the pressing member (8b), and the movable fulcrum member (9) (9) and the elastic fulcrum member (In 1G, beam (7) t-each strip (9b)
Then, connect them with screws (9o) to form a span, then use a weight as a concentrated load, an appropriate number of block-type weights as a partially uniformly distributed load, and then a uniformly distributed load as a weight. By placing an appropriate number of roller chains 1221 of a predetermined length on the beam, a state in which a load is applied to the force is created, and the mechanical phenomenon that changes depending on the load is observed directly visually. You will be able to understand the theory of construction, and also move along the dial gauge mini 2 track (5) in the length direction of the beam (7) to be inspected to measure the amount of deflection or fulcrum stress at the desired location. The length of the beam (7) can be determined by measuring the angle of deflection or by using an optical lever, determining the influence line, Young's coefficient, and detecting the numerical value at each position in the length direction of the beam (7) using a plurality of dial gauges. The form of the bending moment diagram or shear force diagram in the transverse direction can be known, and mechanical experiments of all beam structures such as the one illustrated in FIG. 20 can be easily performed using one device.

In addition, A in Fig. 19 is the simple beam structure shown in Fig. 20 a when a concentrated load weight is applied, and B is the part etc. in the two-span continuous beam structure shown in d. When a block-type weight (goods) for a distributed load is applied, or when a roller chain (221t-) is applied as an evenly distributed load on a cantilever beam of the same e (This shows a mode in which a mirror Q't- is placed at the free end of the force and its vertical movement is measured by using a light lever with a scale C1 ~ interposed, and p is the gel bar of the same 1.
In this way, according to the present invention, several types of specimens with different lengths and widths were used.
Using three types of fulcrum members: fixed, movable, and elastic, a weight for concentrated load, a block-type weight for partially equally distributed load, and a roller chain for equally distributed load, the selected fulcrum member was placed on the experimental support stand. By placing the selected specimen beam at a set position and supporting it to form a span, and by applying an appropriate load of the three types mentioned above or using a combination thereof, the beam can be placed on the support stand in a loose structure. Since it is possible to form a mechanical experimental device as a model, it is possible to easily understand the mechanical theory of various beams and the fluctuations of beams due to loads, making it extremely useful for research and learning of beam structures in civil engineering, architecture, and machinery. Moreover, the structure is relatively simple and low-profile, and the handling operation is easy and simple.

[Brief explanation of the drawing]

The drawings show an embodiment of the device of the present invention; FIG. 1 is a plan view of the entire device, FIG. 2 is a front view, FIG. 3 is a side view, FIG. 4 is a cutaway side view of the fixed fulcrum member, and FIG. Figure 5 is a cut front view, Figure 6 is a cut side view of the movable fulcrum member, Figure 7 is a front view of the stationary movable fulcrum member, Figure 8 is a front view of the horizontally movable fulcrum member, and Figure 9 is the elastic fulcrum member. Figure 1D is a front view of the weight, Figure 11 is a perspective view of the weight, Figure 12 is a perspective view of the block type weight, Figure 15 is a front view of the block type weight in use, and Figure 14 is a front view of the weight. The figure is a plan view of P-Rachen, 15th page.
A is a front view of the device in use, FIG. 16 is a perspective view of a ring for hanging weights, and FIG. 17 is a perspective view of an example of a specimen beam.
FIG. 18 is a perspective view of the Gelber beam, FIG. 19 is a front view showing an aspect of the experimental apparatus according to the present invention, and FIG. 20 is a front line view illustrating the rights of the beam structure. (1)... Experimental support stand (3 bars 4) (5)...
Track (7)... Test vermilion (8)... Fixed fulcrum member (9) (9)... Movable fulcrum member part... Elastic fulcrum member (21... Weight ta... Rokutsuku Type weight (2ri...Roller chain (2)...Dial gauge
Gυ... Measuring element "H2S, 69- 1 n 0 in Fig. 19

Claims (1)

[Claims] An experimental support stand that can be placed horizontally on the floor; three types of fulcrum members for fixed support, movable support, and elastic support that can be moved along the horizontal support and fixed at desired positions;
A test beam of a predetermined size is installed on a support stand using these fulcrum members and supported by it to form a span, and distribution of weights, parts, etc. for concentrated loads on the test beam. Measurement was carried out by moving along the length of a block-shaped weight for loading, a p-ler chain of a predetermined length for uniformly distributed loading, and a test hull with a span formed, and stopping at a predetermined position. A mechanical experimental device with a beam structure consisting of a test beam and an appropriate number of dial gauges that bring the child into contact with a fulcrum member.