Construction method for replacing wood cantilever beam of rammed-earth building

Abstract

The present invention relates to the field of buildings. Disclosed is a construction method for replacing a wood cantilever beam of a rammed-earth building. The construction method for replacing a wood cantilever beam of a rammed-earth building provided in the present invention comprises the following steps: removing the load on an upper part of a wood cantilever beam; machining a plurality of grouting holes along a gable wall from a top end face of the gable wall and perpendicular to a foundation plane, wherein a bottom end face of the grouting hole is lower than the lowest point of the horizontal position of the wood cantilever beam; grouting the grouting holes, and injecting a grouting material; machining a plurality of detachment holes from a side face of the gable wall and directly facing the wood cantilever beam, wherein the detachment holes penetrate same to a surface of the wood cantilever beam; pulling the wood cantilever beam away from the gable wall to remove the wood cantilever beam, and inserting a new wood cantilever beam; and after the wood cantilever beam is replaced, sealing a gap between the wood cantilever beam and the gable wall. The repair requirement and the protection requirement of an existing rammed-earth building for replacing a wood cantilever beam can thus be met.

Description

A construction method for replacing wooden beams in rammed earth buildings Technical Field

[0001] The invention relates to the field of construction, and in particular to a construction method for replacing wooden cantilever beams of rammed earth buildings. Background Art

[0002] Fujian Tulou is listed as one of the world's cultural heritage sites. It is built with stone as the foundation and rammed earth as the main raw material.

[0003] The basic structure of Fujian Tulou is that the outer rear wall is an earth wall. Considering the needs of defense and thermal insulation, the thickness is generally more than 1m. The gable wall is a manually rammed earth wall with a thickness of more than 600mm. The gable wall is manually rammed. When the ramming reaches the bottom of the wooden beam, a rectangular wooden beam is directly embedded in the gable wall. The wooden beam is wrapped with rammed earth. The upper wall and roof load and purlins form a counterweight. The wooden beam is partially embedded in the gable wall, and part of it cantilevers out of the wall surface. The extended part is away from the wall edge. The cantilevered part of the wooden beam forms an eaves with the load-bearing roof above, protecting the upper wall from rain erosion.

[0004] Because the protruding portions of wooden beams are directly exposed to the external environment, they are more susceptible to environmental erosion and insect infestation, which can lead to decay, reduced mechanical properties, and even damage. Therefore, they are one of the most vulnerable load-bearing wooden components in earth buildings. Because they are important load-bearing components and are cantilevered to bear the load, even minor damage such as decay, cross-sectional reduction, and insect infestation requires replacement. However, wooden beams are embedded in the earth walls for a considerable length, generally at a depth of at least 2-2.5 times the length of the protruding beam. For example, if the protruding beam is 1 meter long, the embedded depth should be 2-2.5 meters. Replacing these beams is difficult and challenging, and can easily lead to damage to the gables and excessive interference with the cultural relics.

[0005] Summary of the Invention

[0006] The purpose of the present invention is to provide a construction method for replacing wooden cantilever beams of rammed earth buildings, which can ensure the safety of the rammed earth building structure while replacing the wooden cantilever beams, reduce interference with the original building, and meet the needs of repairing and protecting the wooden cantilever beams of rammed earth buildings.

[0007] In order to solve the above technical problems, the embodiments of the present invention provide a technical solution as follows:

[0008] A construction method for replacing wooden cantilever beams in rammed earth buildings comprises the following steps:

[0009] Unload the load on the top of the wooden beam;

[0010] A plurality of grouting holes are machined from the top end surface of the gable wall along the gable wall perpendicular to the foundation plane, wherein the bottom end surface of the grouting holes is lower than the lowest point of the horizontal position of the wooden cantilever beam;

[0011] Grouting the grouting holes and injecting grouting materials;

[0012] A plurality of escape holes are machined from the side of the gable wall facing the wooden beam, wherein the escape holes penetrate to the surface of the wooden beam;

[0013] Remove the wooden beams from the gable wall and insert new ones;

[0014] After the wooden beam is replaced, the gap between the wooden beam and the gable is sealed.

[0015] Furthermore, the unloading of the load on the upper part of the wooden cantilever beam includes dismantling the roofs of the rooms on both sides of the gable where the wooden cantilever beam is located, and the roofs include tiles, rafters, eaves boards and roof purlins on both sides of the gable.

[0016] Furthermore, the grouting pressure is 0.2MPA-0.3MPA.

[0017] Furthermore, the grouting holes are symmetrically arranged on both sides of the wooden cantilever beam, and the grouting holes are evenly distributed laterally along both sides of the wooden cantilever beam.

[0018] Furthermore, the vertical distance between the central axis of the grouting hole and the side surface of the gable is 100MM-200MM, and the center distance between the grouting holes on the same side of adjacent wooden cantilever beams is 150MM-300MM.

[0019] Furthermore, the vertical distance between the bottom end surface of the grouting hole and the lowest point of the horizontal position of the wooden cantilever beam is 100MM-500MM.

[0020] Furthermore, the grouting hole is a circular hole, and the diameter of the grouting hole is 50MM-150MM.

[0021] Furthermore, the escape hole is a conical hole, which is symmetrically arranged on both sides of the wooden beam. The end with the larger opening of the escape hole faces the wooden beam, and the bottoms of the two relatively arranged escape holes are connected.

[0022] Furthermore, the horizontal cross-section of the escape hole is a trapezoid, and the angle between the waist and the lower base of the trapezoid is 40°-50°.

[0023] Furthermore, the horizontal center distance of the escape holes is 800MM-1200MM.

[0024] Furthermore, the upper boundary of the escape hole in the vertical direction is 20MM-50MM higher than the upper boundary of the wooden cantilever beam, and the lower boundary of the escape hole in the vertical direction is 20MM-50MM lower than the lower boundary of the wooden cantilever beam.

[0025] Furthermore, the grouting holes and wooden beams are avoided during the processing of the escape holes.

[0026] Furthermore, the grouting material composition is lime:cement:fly ash:water=0.5:1:0.3:0.9 in weight ratio.

[0027] Furthermore, before the release hole is processed, the compressive strength of the grouting material needs to reach 15 MPA.

[0028] Furthermore, the method of sealing the gap between the wooden cantilever beam and the gable wall includes using hardwood strips to fill the gap between the wooden cantilever beam and the upper and lower gable walls.

[0029] Compared with the prior art, the construction method for replacing wooden cantilever beams of rammed earth buildings provided by the present invention reinforces the gable wall by processing grouting holes and injecting grouting materials, and enables the wooden cantilever beams to be separated from the gable wall for replacement by processing detachment holes. During the replacement process, the firmness of the gable wall can be effectively guaranteed, and large-scale damage to the gable wall or rammed earth building can be avoided. The principle of minimum intervention required for cultural relics repair is followed, and the original form of the wooden cantilever beam located in the middle of the gable is preserved. It can meet the repair and protection needs of existing rammed earth buildings for replacing wooden cantilever beams. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0031] FIG1 is a schematic diagram of the overall structure of a rammed earth building according to the present invention;

[0032] FIG2 is a schematic diagram of the location distribution of grouting holes in the gable wall of the present invention;

[0033] FIG3 is a schematic diagram of a partial cross-sectional structure of a gable in the present invention;

[0034] FIG4 is a cross-sectional view taken along line AA in FIG3 .

[0035] Explanation of the accompanying reference numerals: 1. rear wall; 2. gable; 3. roof; 4. wooden beam; 41. supporting end; 42. fixed end; 5. grouting hole; 6. release hole. DETAILED DESCRIPTION

[0036] To make the objectives, technical solutions, and advantages of the present invention more apparent, various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will appreciate that many technical details are provided in various embodiments of the present invention to facilitate a better understanding of the present application. However, even without these technical details and the various variations and modifications based on the following embodiments, the technical solutions claimed in the claims of this application can be implemented.

[0037] In one embodiment of the present invention, a construction method for replacing a wooden cantilever beam 4 of a rammed earth building is provided, comprising the following steps:

[0038] Unloading the load on the upper part of the wooden beam 4;

[0039] A plurality of grouting holes 5 are machined from the top end surface of the gable 2 along the gable 2 perpendicular to the foundation plane, and the bottom end surface of the grouting hole 5 is lower than the lowest point of the horizontal position of the wooden cantilever beam 4;

[0040] Grouting the grouting hole 5 by injecting grouting material;

[0041] A plurality of escape holes 6 are machined from the side of the gable 2 facing the wooden beam 4, and the escape holes 6 penetrate to the surface of the wooden beam 4;

[0042] Pull out the wooden beam 4 from the gable 2 and insert a new wooden beam 4;

[0043] After the wooden beam 4 is replaced, the gap between the wooden beam 4 and the gable 2 is sealed.

[0044] As shown in Figures 1-4, in another embodiment of the present invention, the rammed earth building structure in the construction method for replacing the wooden cantilever beam 4 of the rammed earth building provided by the present invention includes a rear wall 1 and a gable 2 arranged perpendicular to the rear wall 1, and the gable 2 is used to divide the internal space of the rammed earth building; a wooden cantilever beam 4 is buried in the upper end of the gable 2, and the wooden cantilever beam 4 includes a supporting end 41 extending out of the wall and a fixed end 42 buried in the wall; the top of the gable 2 is in the shape of a mountain, and a roof 3 is provided on the top of the gable 2. The roof 3 is arranged corresponding to the gable 2 and is roughly in the shape of a mountain. The highest point of the roof 3 is the ridge, and the roof 3 extends downward from the wall from the ridge to both sides, and the extension surface of the roof 3 intersects with the supporting end 41 of the wooden cantilever beam 4, and the supporting end 41 supports the roof 3. The roof 3 includes tiles, rafters, eaves boards and purlins.

[0045] In rammed earth buildings such as tulou, wooden beams 4 are important load-bearing components. Therefore, damage to wooden beams 4 can pose a significant safety hazard and require prompt replacement. Before replacement, wooden beams 4 need to be inspected for signs of decay, reduced cross-section, or insect damage. Damaged beams 4 are marked and replaced.

[0046] When replacing the wooden beam 4 embedded in the gable 2, first, remove the load on the upper part of the wooden beam 4; that is, remove the roof 3 on the upper part and both sides of the gable 2, such as tiles, rafters, eaves boards and purlins; then, from the top end face of the gable 2, process multiple grouting holes 5 along the vertical foundation plane of the gable 2, and the bottom end face of the grouting holes 5 is lower than the lowest point of the horizontal position of the wooden beam 4; at the top of the gable 2 where the wooden beam 4 is embedded, process multiple grouting holes 5 vertically downward from the foundation, and the grouting holes 5 are preferably processed by drilling technology, and the depth of the drilling needs to exceed the bottom of the wooden beam 4. Preferably, the diameter of the grouting hole 5 is 50MM-100MM, and preferably, the bottom end face of the grouting hole 5 exceeds the bottom of the wooden beam 4 by 100MM-500 MM, the grouting holes 5 are evenly distributed on both sides of the wooden cantilever beam 4, and are distributed in piles along the wooden cantilever beam 4. The distance from the central axis of the grouting hole 5 to the surface of the wooden cantilever beam 4 is greater than 100MM. Preferably, the distance from the central axis of the grouting hole 5 to the side of the gable 2 is greater than 100MM, and the distance from the central axis of the grouting hole 5 to the surface of the wooden cantilever beam 4 is 100MM-200MM. The grouting holes 5 on the same side of the wooden cantilever beam 4 are evenly spaced in the horizontal direction, and the center distance between two adjacent grouting holes 5 is 150-300MM; then, the grouting holes 5 are grouted with grouting material, and the grouting pressure is 0.2MPA-0.3MPA. In order to avoid perforation during grouting, drilling grouting should be implemented at intervals. After drilling the grouting holes 5, high-pressure gas is used to clean the interior of the holes to remove debris. Before grouting, the holes are first moistened with water. Grouting materials can include construction mud, concrete, etc. Preferably, the weight ratio of the grouting material is: lime: cement: fly ash: water = 0.5:1:0.3:0.9. Grouting the grouting holes 5 creates a more solid overall structure for the gable wall 2, thus strengthening the wall. After the grouting material solidifies to a compressive strength of 15MPA, a release hole 6 is machined from the side of the gable 2 facing the wooden cantilever beam 4 along the central axis of the wooden cantilever beam 4. There can be multiple release holes 6, and the release holes 6 are connected to the surface of the wooden cantilever beam 4. Preferably, the release holes 6 are relatively arranged, that is, symmetrically arranged along the two sides of the wooden cantilever beam 4; preferably, the release holes 6 are conical holes, and the end with the larger opening of the release hole 6 faces the wooden cantilever beam 4, and the bottoms of the two relatively arranged release holes 6 are connected; when processing the release holes 6, avoid the grouting holes 5 and the wooden cantilever beam 4, and do not damage the wooden cantilever beam 4 and the grouting material in the grouting holes 5. The horizontal cross-section of the release hole 6 is a trapezoid, and the angle between the waist of the trapezoid and the lower base is 40°-50°.

[0047] The horizontal center distance of the disengagement hole 6 is 800MM-1200MM. Preferably, the upper boundary of the disengagement hole 6 in the vertical direction is 20MM-50MM higher than the upper boundary of the wooden cantilever beam 4, and the lower boundary of the disengagement hole 6 in the vertical direction is 20MM-50MM lower than the lower boundary of the wooden cantilever beam 4, so that the wooden cantilever beam 4 can be detached from the gable 2 wall and taken out smoothly. After the damaged wooden cantilever beam 4 is taken out, a new wooden cantilever beam 4 is inserted in the original position, and the position of the new wooden cantilever beam 4 is calibrated and checked. After the verification is completed, the gap between the wooden cantilever beam 4 and the gable 2 wall is sealed. Preferably, the gap between the wooden cantilever beam 4 and the upper and lower walls of the gable 2 is sealed with hardwood picks. According to the size of the gap, hardwood strips of appropriate thickness are selected and stuffed into the gap between the wooden cantilever beam 4 and the upper and lower walls of the gable 2, so that the wooden cantilever beam 4 and the gable 2 wall are relatively fixed. Finally, the roof 3 is restored, and the purlins, rafters, eaves boards, tiles, etc. are put back in place according to the original structure, completing the replacement construction of the wooden cantilever beam 4.

[0048] In one embodiment, the thickness of the gable 2 is 800MM, and the wooden cantilever beam 4 is centrally arranged in the wall of the gable 2. The cross-section of the wooden cantilever beam 4 is rectangular, the length of the rectangle is 350MM, and the width is 180MM. The width of the rectangle is set corresponding to the thickness of the gable 2, and the length of the rectangle is set along the height direction of the gable 2. After unloading the wooden cantilever beam 4, grouting holes 5 are processed on the top end face of the gable 2 corresponding to the wooden cantilever beam 4. The diameter of the grouting hole 5 is 80MM. The grouting hole 5 is processed perpendicular to the foundation plane. The depth of the grouting hole 5 is that the bottom end face of the grouting hole 5 is lower than the bottom of the wooden cantilever beam 4. Preferably, the distance between the bottom end face of the grouting hole 5 and the bottom face of the wooden cantilever beam 4 is 300MM. The grouting holes 5 are processed along the extension direction of the wooden cantilever beam 4 and are symmetrically arranged relative to the wooden cantilever beam 4. The grouting holes 5 on the same side of the wooden cantilever beam 4 are evenly spaced, and the center distance between two adjacent grouting holes 5 is 200MM. The distance between the grouting holes 5 and the side surface of the adjacent gable 2 wall is 145MM. The grouting material for grouting hole 5 adopts the component weight ratio of: lime: cement: fly ash: water = 0.5:1:0.3:0.9, the grouting pressure is 0.2MPA-0.3MPA, and the grouting material is made into a 70.7MM×70.7MM×70.7MM cubic test block with the same conditions for retention. After the grouting material solidifies until the compressive strength reaches 15MPA, the detachment hole 6 is processed along the horizontal axis of the wooden cantilever beam 4. The vertical cross-section of the detachment hole 6 is rectangular, and the vertical height is 430MM. The horizontal center line of the detachment hole 6 is aligned with the center axis of the wooden cantilever beam 4, that is, the vertical distance between the upper boundary of the detachment hole 6 and the upper end face of the wooden cantilever beam 4 is 40MM, and the vertical distance between the lower boundary of the detachment hole 6 and the lower end face of the wooden cantilever beam 4 is 40MM; the horizontal cross-section of the detachment hole 6 is trapezoidal, and the waist of the trapezoid is aligned with the lower bottom. The angle is 45°, the horizontal center distance of the two adjacent detachment holes 6 on the same side of the wooden cantilever beam 4 is 1000MM, and the bottoms of the two symmetrically arranged detachment holes 6 are connected to facilitate the detachment of the wooden cantilever beam 4 from the gable wall 2. The damaged wooden cantilever beam 4 is pulled out from the gable wall 2, and a new wooden cantilever beam 4 is inserted. Then the position of the wooden cantilever beam 4 is corrected. After the position is confirmed, a hardwood strip with a width of 80MM × thickness of 40MM is inserted into the gap between the wooden cantilever beam 4 and the upper and lower walls of the gable 2. The length of the hardwood strip corresponds to the length of the wooden cantilever beam 4 buried in the gable wall 2. Finally, use cement to seal the remaining gap between the wooden cantilever beam 4 and the wall. After the cement solidifies, restore the roof 3.

[0049] The construction method for replacing wooden cantilever beams of rammed earth buildings provided by the present invention first reinforces the gable wall by setting grouting holes, and then enables the wooden cantilever beams to be separated from the gable for replacement by processing the detachment holes. During the replacement process, the structural safety can be effectively guaranteed, and large-scale damage to the gable or rammed earth building can be avoided. The minimum intervention principle required for cultural relics restoration is followed, and the original form of the wooden cantilever beams located in the middle of the gable is preserved. This method can meet the repair and protection needs of existing rammed earth buildings for replacing wooden cantilever beams.

[0050] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A construction method for replacing wooden beams in rammed earth buildings, characterized in that: The steps include: Remove the load from the top of the wooden beam; A plurality of grouting holes are processed from the top end surface of the gable wall along the vertical foundation plane of the gable wall, and the bottom end surface of the grouting holes is lower than the lowest point of the horizontal position of the wooden cantilever beam; Grouting the grouting holes by injecting grouting materials; A plurality of escape holes are processed from the side of the gable wall directly facing the wooden beam, and the escape holes penetrate to the surface of the wooden beam; Remove the wooden beams from the gable and insert new wooden beams; After the wooden cantilever beam is replaced, the gap between the wooden cantilever beam and the gable is sealed.

2. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The method of removing the load on the upper part of the wooden beam comprises removing the roofs of the rooms on both sides of the gable where the wooden beam is located, wherein the roof comprises tiles, rafters, eaves boards and the roof purlins on both sides of the gable are removed.

3. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The grouting pressure is 0.2MPA-0.3MPA.

4. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The grouting holes are symmetrically arranged on both sides of the wooden cantilever beam, and the grouting holes are evenly distributed laterally along both sides of the wooden cantilever beam.

5. The construction method for replacing wooden beams in rammed earth buildings according to claim 4, characterized in that: The vertical distance between the central axis of the grouting hole and the side surface of the gable is 100MM-200MM, and the center distance between the grouting holes on the same side of adjacent wooden cantilever beams is 150MM-300MM.

6. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The vertical distance between the bottom end surface of the grouting hole and the lowest point of the horizontal position of the wooden cantilever beam is 100MM-500MM.

7. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The grouting hole is a circular hole, and the diameter of the grouting hole is 50MM-150MM.

8. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The escape holes are conical holes, which are symmetrically arranged on both sides of the wooden beam. The ends of the escape holes with larger cross-sectional openings face the wooden beam, and the bottoms of the two escape holes arranged opposite to each other are connected.

9. The construction method for replacing wooden beams in rammed earth buildings according to claim 8, characterized in that: The horizontal cross section of the escape hole is a trapezoid, and the angle between the waist and the lower base of the trapezoid is 40°-50°.

10. The construction method for replacing wooden beams in rammed earth buildings according to claim 8, characterized in that: The horizontal center distance of the escape holes is 800MM-1200MM.

11. The construction method for replacing wooden beams in rammed earth buildings according to claim 8, characterized in that: The upper boundary of the detachment hole in the vertical direction is 20MM-50MM higher than the upper boundary of the wooden cantilever beam, and the lower boundary of the detachment hole in the vertical direction is 20MM-50MM lower than the lower boundary of the wooden cantilever beam.

12. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The grouting holes and wooden beams are avoided during the processing of the escape holes.

13. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The grouting material composition is lime:cement:fly ash:water=0.5:1:0.3:0.9 in weight ratio.

14. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: Before the release hole is processed, the compressive strength of the grouting material needs to reach 15 MPA.

15. The construction method for replacing wooden beams in rammed earth buildings according to claim 1, characterized in that: The method of sealing the gap between the wooden cantilever beam and the gable wall comprises using hardwood strips to fill the gap between the wooden cantilever beam and the upper and lower gable walls.

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