RU2770504C1 - Method for testing three-layer exterior walls (options) - Google Patents

Abstract

FIELD: construction industry.SUBSTANCE: invention relates to construction, namely to the testing of constructions of buildings and structures. The method for testing three-layer exterior walls with a front layer of brick, masonry with flexible connections for bending from the plane consists in applying a load by means of distribution beams and a jack. The jack is located in a hole in the inner layer of the test bench wall. A metal beam rigidly fixed to a concrete wall is used as a stop for the jack. The method for testing three-layer outer walls containing support beams, metal brackets bearing the masonry of the front layer of the outer wall for a vertical load consists in applying a load evenly distributed over the width of the tested fragment of the wall. The load is applied using a jack. The jack rests against a horizontal composite metal beam passing through a hole in the inner layer of the wall.EFFECT: increase in the accuracy of assessing the strength characteristics of the elements of a three-layer outer wall is achieved when working as part of a single structure with active and passive wind action.2 cl, 9 dwg

Description

The essence of the invention

The technical objective of the invention is to expand the scope of testing and calculation of three-layer external walls with flexible connections when exposed to wind loads.

The technical result that can be obtained using the claimed method is to increase the accuracy of assessing the strength characteristics of the elements of a three-layer outer wall when working as part of one structure with active and passive wind action.

The problem is solved by testing three-layer walls using a system of beams and a jack installed in a hole in the inner layer of the wall. The jack is supported by a metal beam rigidly fixed to the inner layer of the wall. At the first stage, tests are carried out for the active action of the wind by applying the calculated distributed load on the front layer of the wall in the direction of the inner layer, at the second stage, the bearing capacity of the three-layer wall for the passive action of the wind is determined by applying the load from the inner layer of the wall. The next step is to test the support beam (bracket) for vertical load. In this case, the distribution beam is mounted on a support beam (bracket), on top of which a jack is installed. When the load is applied, the jack is supported by a horizontal composite beam passing through a hole in the inner layer of the wall.

This method is implemented using a specially designed stand (Fig. No. 7-9), including a base and a vertical wall made of reinforced concrete. The wall has holes for installing jacks and beams. The shape of the base is similar to the end of the ceiling, which should take the load from the front layer of the wall and can be made in the form of a parallelepiped, or with cantilever ledges, between which a heater is installed, or with openings for thermal breaks. If necessary, a metal plate is placed under the stand base to fix the deflection of the support beam (bracket) after loading.

Brief description of the drawings

In FIG. 1 shows a method for testing the face layer of masonry with flexible ties for the active action of the wind using a test bench;

in fig. 2 - hinge base plate assembly;

in fig. 3 - method for testing the front layer of masonry with flexible ties for the passive action of the wind using a test bench;

in fig. 4 - method of testing the support beam (bracket) for vertical load using a test stand;

in fig. 5 - a variant of testing a three-layer wall for the active action of the wind with support brackets installed on the inner wall at two levels in height;

in fig. 6 - a variant of testing a three-layer wall for active wind action with a support bracket installed on the inner wall under the front layer of masonry.

Implementation of the invention

The test method for the active action of the wind (Fig. 1) includes:

1 - test stand

2 - masonry of the front layer

3 - flexible connections

4 - support beam (bracket)

5 - jack

6 - thrust beam-channel under the jack

7 - frame made of box-section beams connected by steel rods in the form of studs

8 - channel distribution beams

9 - hinged support plates (Fig. 2), transferring the load from the jack 5 to the masonry 2 and flexible connections 3

10 - distribution beam in the form of an I-beam

11 - horizontal thrust composite beam of channels

The essence of this method is as follows. The jacks 5, installed in the holes, on the one hand rest against the horizontal channel beams 6, rigidly fixed to the concrete wall of the test bench 1. Distribution channel beams 8 with hinged support plates 9 are installed on the outside of the masonry. Frame 7 of box-section beams and studs encircles the entire structure. When pressure is applied to the jack 5, the load is transferred through the frame to the distribution beams 8 and further through the support plates 9 to the masonry layer 2 and flexible connections 3. Thus, bending occurs from the plane of the masonry, and the connections, in turn, work in compression. Loading is carried out step by step with fixing the deformation of the elements using measuring instruments.

The method of testing for the passive action of the wind (Fig. 3) differs from the above method in that the jack 5 transfers the load in the opposite direction towards the masonry, while the distribution beams in the form of I-beams 10 are located behind the masonry of the front layer 2. In this embodiment, there is no need to use frames. Bending masonry 2 is already in the other direction, and flexible connections 3 work for pull.

The method of testing the support beam (bracket) 6 under the front layer of masonry for a vertical load (Fig. 4) is that the jack 5 rests against a horizontal thrust composite beam 11 passing through a hole in the inner wall of the building, or stand 1. The beam is made of channels connected with studs and expanded by means of nuts tension, which ensures their reliable fastening with a reinforced concrete wall. The load from the jack 5 is transmitted through the distribution beam-I-beam 10. If the total height of the jack 5 and the distribution beam-I-beam 10 is not enough, then the missing part of the height can be obtained by performing masonry 2 on top of the support beam (bracket) 6. Loading is carried out step by step with fixation of the deformation of the elements using measuring instruments.

With these methods it is possible to test most types of three-layer external walls. In FIG. 5 shows an example of applying the method of testing a three-layer wall for the active action of the wind when the front layer of masonry 2 is supported on metal support brackets 4 located in two levels along the height of one floor. In this case, the support brackets are fastened to the reinforced concrete wall 1. In this embodiment, the distribution channel beams 8 are divided into two parts separately for each section of the front layer of the masonry 2 with the support bracket 4.

In FIG. 6 shows an example of applying the method of testing a three-layer wall for the active action of the wind when the front layer of masonry 2 is supported on a metal support bracket 4, fixed to a reinforced concrete wall 1.

When testing the walls by the above methods, the work of flexible connections is taken into account both for pull-out under the passive influence of the wind, and for compression under the active influence of the wind, as well as the compliance of the support under the masonry of the front layer.

The results of testing three-layer walls by these methods are the limiting horizontal displacements of the masonry of the front layer, the limiting forces in the bonds, the limiting forces and total displacements in the anchoring points of the bonds in the front and inner layers of the wall, taking into account the compression of the vertical load and the connection structure, the limiting vertical movements of the support under the masonry of the front layer.

The results of the work carried out can be used in the design of three-layer outer walls in multi-storey buildings and structures.

Claims (2)

1. A method for testing three-layer external walls with a front layer of brick, masonry with flexible ties for bending out of plane, characterized in that the load is applied by means of distribution beams and a jack located in a hole in the inner layer of the wall of the test bench, moreover, as a stop for The jack uses a metal beam rigidly fixed to a concrete wall. 2. A method for testing three-layer external walls containing support beams, metal brackets bearing the masonry of the front layer of the external wall, for a vertical load, characterized in that it includes the application of a load uniformly distributed over the width of the tested wall fragment, and the load is applied using a jack resting into a horizontal composite metal beam passing through a hole in the inner layer of the wall.

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