A kiln tail layering reinforcement structure and method
By adding a foundation and steel support structure to the outside of the kiln tail frame and using prestressed steel strands to transfer the load, the problem of insufficient foundation bearing capacity was solved, achieving rapid and safe reinforcement and avoiding damage to the original structure and its functionality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SINOMA INT ENG
- Filing Date
- 2023-12-26
- Publication Date
- 2026-06-12
AI Technical Summary
When upgrading the existing kiln tail frame to a six-stage preheater, the foundation bearing capacity is insufficient, resulting in high construction difficulty, long construction period and impact on the building's functionality. Existing reinforcement methods cannot effectively solve this problem.
A combined reinforcement method using steel support structure and prestressed steel strands is adopted. By adding a foundation and steel support to the outside of the original frame, the load is transferred to the new foundation using prestressed steel strands, thereby strengthening the frame and avoiding damage to the original structure and impact on the internal space.
It achieves the goal of strengthening the foundation bearing capacity without damaging the original structure, shortening the construction period, improving safety and economic benefits, and without affecting the internal use functions of the building.
Smart Images
Figure CN117781703B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of kiln tail reinforcement technology, and in particular to a kiln tail layer reinforcement structure and method. Background Technology
[0002] The current downward trend in cement demand is prominent, coupled with persistently high energy prices. The combination of weak demand, falling prices, and high inventory levels has exacerbated the cement industry's slump. "Energy conservation, carbon reduction, cost reduction, and efficiency improvement" have become key breakthroughs for many cement companies to enhance their overall strength and market competitiveness. Most of the early 5000t / d production lines used five-stage preheaters. Replacing them with six-stage preheaters would offer significant advantages in reducing energy consumption and greatly contribute to energy conservation and emission reduction. The upgrade from five to six stages presents no major challenges in terms of technology, equipment, and processes; the main difficulty lies in the safety of the building structure, with insufficient foundation bearing capacity having a veto power over the project. Upgrading from a five-stage to a six-stage preheater increases the load on the kiln tail frame, leading to insufficient bearing capacity of the original frame columns and foundations, necessitating reinforcement and modification of the original structure.
[0003] There are three main types of existing kiln tail foundation reinforcement structures and methods:
[0004] (1) Strengthen the foundation by increasing the bottom area of the foundation. Roughen the surface of the original concrete foundation, insert steel bars into the old foundation by means of rebar installation or welding, and pour concrete. For example, a reinforcement method proposed by Chinese Patent Publication No. CN114875947A uses precast concrete slabs as templates, lays steel bars to form an integral steel skeleton with the original foundation, and then pours concrete to make the two form an integral whole.
[0005] (2) Lay new piles at a suitable location near the original pile foundation. When the pile strength reaches the design requirements, roughen the original pile cap and insert steel bars by planting or welding. Cast the original pile cap and the new pile cap into a whole pile cap to share the load. For example, the invention patent with Chinese patent publication number CN103741963A proposes a new steel pipe column and a new concrete pile cap. After the new pile cap and the original foundation pile cap are connected by steel bar anchoring, they share the load of the new added structure.
[0006] (3) Diagonal bracing reinforcement, such as the reinforcement structure for insufficient bearing capacity of frame columns and foundations disclosed in Chinese Patent Publication No. CN217812516U. This patent transfers the overload to the new foundation by arranging diagonal bracing between frame columns and adding a new foundation.
[0007] Both methods 1 and 2 require excavating the existing foundation and treating it to ensure that the new structure and the original structure can form a whole and share the load. This makes construction difficult, and the newly poured concrete also needs a long time to reach the strength and stability required by the design, resulting in a long construction cycle.
[0008] Although method 3 above does not require reinforcement of the original foundation, it still requires the addition of a connecting beam between the original foundation and the new foundation to connect them, and the original foundation needs to be excavated. Moreover, for the kiln tail frame, there are already foundation beams between the columns, and infill walls are placed on the beams. It is inconvenient to set up new foundations and diagonal braces inside the frame, which would affect the functionality of the building. Therefore, this reinforcement method is not suitable for kiln tail reinforcement. Summary of the Invention
[0009] Purpose of the invention: The purpose of this invention is to provide a kiln tail reinforcement structure and method that does not damage the original structural foundation, does not change the internal space of the frame, has a short construction period, and is highly safe.
[0010] Technical Solution: The present invention provides a kiln tail reinforcement structure, comprising an original kiln tail frame, a first floor, and a second floor. The original kiln tail frame includes a left foundation, a middle foundation, a right foundation, a left-axis concrete column, a middle-axis concrete column, a right-axis concrete column, a left-axis steel column, a middle-axis steel column, and a right-axis steel column. A first-floor left-side concrete beam is provided between the left-axis and middle-axis concrete columns, and a first-floor right-side concrete beam is provided between the middle-axis and right-axis concrete columns. A second-floor left-side steel beam is provided between the left-axis and middle-axis steel columns, and a second-floor right-side steel beam is provided between the middle-axis and right-axis steel columns. The structure also includes several additional foundations symmetrically arranged outside the left and right foundations, each additional foundation having a steel support at its top. The steel support structure includes a vertically arranged lower steel pipe and an obliquely arranged upper steel pipe. The bottom end of the lower steel pipe is fixedly connected to the top of the new foundation, and the top end is fixedly connected to the bottom of the upper steel pipe. The top of the upper steel pipe is fixedly connected to the outer side of the left-side and right-side steel columns. The left-side, middle-side, and right-side concrete columns are respectively provided with a first fixing part, a second fixing part, and a third fixing part at their contact points with the upper surface of the first floor. The left-side and right-side steel columns are provided with a fourth fixing part and a fifth fixing part at their contact points with the lower surface of the second floor. A first set of prestressed steel strands is provided between the second fixing part and the fourth and fifth fixing parts. A second set of prestressed steel strands is provided between the first fixing part, the third fixing part, and the lower steel pipe parallel to them.
[0011] Furthermore, the second fixing part includes first steel plates symmetrically embedded on the front and rear sides of the intermediate shaft concrete column. Several first channel steels are welded transversely on the first steel plates. Second steel plates are welded to both ends of the first channel steels respectively. Several holes matching the number of steel strands are opened on the second steel plates. First tensioning end clamps for tensioning the first group of prestressed steel strands are welded to the inner side of the second steel plates according to the position of the holes. The fourth and fifth fixing parts are both welded with first node plates. First anchoring end clamps for anchoring the first group of prestressed steel strands are welded to the first node plates.
[0012] Furthermore, the top of the newly added foundation is provided with a first hinge support, the lower steel pipe is hinged to the newly added foundation through the first hinge support, the top of the lower steel pipe is provided with a second hinge support, the bottom of the upper steel pipe is hinged to the lower steel pipe through the second hinge support, and the outer sides of the left and right steel beams of the second floor are provided with a third hinge support, the top of the upper steel pipe is hinged to the third hinge support.
[0013] Furthermore, both the first and third fixing parts are equipped with a three-sided ring hoop welded from steel plates and second channel steel. The opening of the ring hoop faces outward from the frame, and a third steel plate is welded to the end of the opening side of the ring hoop. Several holes matching the number of steel strands are opened on the third steel plate. A second tensioning end clamp for tensioning the second set of prestressed steel strands is welded to the inner side of the third steel plate according to the position of the holes. The bottom plate of the second hinge shaft support is flush with the top surface of the ring hoop. A fastener is provided at the top of the lower steel pipe, close to the second hinge shaft support. A second anchoring end clamp for anchoring the second set of prestressed steel strands is welded to the fastener. The height of the second anchoring end clamp is the same as the height of the second tensioning end clamp.
[0014] Furthermore, second node plates are symmetrically welded to the outer sides of the left and right steel beams of the second floor, the third hinge support is installed on the second node plate, and reinforcing ribs are welded to the nodes of the second node plate.
[0015] Furthermore, the first steel plate is pre-embedded on both the front and rear sides of the intermediate shaft concrete column using chemical anchors and steel plate installation.
[0016] Furthermore, the first anchoring end clamp faces the second fixing part.
[0017] Furthermore, the first group of prestressed steel strands and the second group of prestressed steel strands each have two groups.
[0018] A method for reinforcing the kiln tail layer includes the following reinforcement steps:
[0019] S1: Based on the increased load of the original kiln tail frame, the dimensions of the bottom frame, the available space around the kiln tail frame, and the bearing capacity of the foundation, use general structural design software to model and calculate to determine the location and dimensions of the new foundation, the cross section of the steel support structure, and the tension parameters of the first set of prestressed steel strands and the second set of prestressed steel strands.
[0020] S2: Construct new foundations on the outside of the original kiln tail frame's left and right foundations, and install the first hinge shaft support on the pre-embedded anchor bolts on the top of the new foundations to fix and install the lower steel pipes.
[0021] S3: On the first floor, near the height of the first floor, chemical anchors and steel plates are used to symmetrically install the first steel plates on both the front and back sides of the intermediate axis concrete column. Several first channel steels are welded horizontally on the first steel plates, and second steel plates are welded to both ends of the first channel steels. Several holes matching the number of steel strands are opened on the second steel plates. The first tensioning end clamps of the first set of prestressed steel strands are welded to the inner side of the second steel plates according to the position of the holes. On the outer side of the left axis concrete column and the outer side of the right axis concrete column, at the height of the first floor, a three-sided hoop is welded using steel plates and second channel steels. The hoop opening faces the outer side of the frame. A third steel plate is welded to the open end of the hoop. Several holes matching the number of steel strands are opened on the third steel plate. The second tensioning end clamps of the second set of prestressed steel strands are welded to the inner side of the third steel plate according to the position of the holes.
[0022] S4: Weld the first node plate at the bottom of the steel beam on the left side of the second floor and the right side of the steel column on the left axis, and weld the first anchoring end clamp of the first set of prestressed steel strands on the first node plate. The opening direction of the first anchoring end clamp is towards the contact part between the first floor and the intermediate axis concrete column on the corresponding side.
[0023] S5: At the height of the second floor of the kiln tail frame, the second node plates are symmetrically welded to the outer sides of the left and right axis steel columns, the third hinge shaft support is installed, and stiffening ribs are welded to the beam-column joint where the second node plate is located for reinforcement.
[0024] S6: The steel supports on the outside of the symmetrical frame are installed, and the bottom end of the lower steel pipe is connected to the hinge support 13 at the top of the newly built foundation on the outside of the frame; the upper steel pipe is installed obliquely, and the top end is connected to the third hinge support on the outside of the left and right columns of the second floor. The top end of the lower steel pipe is connected to the bottom end of the upper steel pipe through the second hinge support. The bottom plate of the second hinge support is flush with the top surface of the hoop. A fastener is installed at the top of the lower steel pipe close to the second hinge support, and the second anchoring end clamp of the second set of prestressed steel strands is welded on the fastener. The height of the second anchoring end clamp is the same as the height of the second tensioning end clamp.
[0025] S7: On the frame, with the central axis of the intermediate foundation as the axis of symmetry, two sets of first-group prestressed steel strands and two sets of second-group prestressed steel strands are symmetrically installed. One end of the second-group prestressed steel strands is anchored by the second anchoring end clamp, and the other end is fixed on the second tensioning end clamp; one end of the first-group prestressed steel strands is anchored by the first anchoring end clamp, and the other end is installed on the first tensioning end clamp.
[0026] S8: Install tensioning equipment on the first floor to tension the first and second sets of prestressed steel strands respectively. After reaching the design tension, anchor them. After tensioning is completed, inspect and accept them. Once it is confirmed that there are no problems, cut off the excess part of the steel strands, remove the tensioning equipment, and complete the reinforcement.
[0027] Furthermore, the tensioning steps for the two sets of steel strands in S8 are as follows: First, the second set of prestressed steel strands is tensioned and anchored after reaching the design required tension force. All the loads that the original frame will increase due to the addition of layers are transferred from the left-side foundation to the newly added foundation outside the frame. Then, the first set of prestressed steel strands is tensioned and anchored after reaching the design required tension force. The loads that the middle foundation will increase due to the addition of layers are transferred to the left-side foundation and the right-side foundation.
[0028] Beneficial effects: Compared with the prior art, the present invention has the following advantages:
[0029] (1) This invention can reinforce the original foundation bearing capacity caused by the addition of layers to the kiln tail frame without damaging the original foundation, without damaging the original structure, and with high construction safety.
[0030] (2) The reinforcement of the present invention does not affect the space inside the original first-floor frame and does not change the original use of the ground floor of the building;
[0031] (3) In the reinforcement process, the original equipment load does not need to be unloaded. Most of the preparatory work before prestressing tensioning can be carried out in sections at the same time, which makes the construction speed fast and greatly shortens the construction period of the entire reinforcement.
[0032] (4) The main reinforcing component of this invention is a steel structure, which makes it easier to control the quality of the reinforcement;
[0033] (5) The tensioning of the final prestressed steel strands in this invention is carried out on the floor plan, which is simple and convenient to operate and has low construction difficulty;
[0034] (6) Most of the reinforcement work of the present invention can be carried out before the kiln is shut down, which effectively reduces the kiln shutdown cycle and improves economic benefits. Attached Figure Description
[0035] Figure 1 A schematic plan view of the newly added foundation for the kiln tail frame according to the present invention;
[0036] Figure 2 This is a schematic elevation view of a frame in the reinforcement method described in this invention;
[0037] Figure 3 This is a schematic diagram of the first set of prestressed steel strand installation structure described in this invention;
[0038] Figure 4 This is a schematic diagram of the second set of prestressed steel strand installation structure described in this invention;
[0039] Figure 5 This is a simplified schematic diagram of the force flow direction on the frame when tensioning the second set of prestressed steel strands as described in this invention;
[0040] Figure 6 This is a simplified schematic diagram of the force flow direction on the frame when tensioning the first set of prestressed steel strands as described in this invention.
[0041] Figure 7 This is a schematic diagram of the embedded part structure on the intermediate shaft concrete column described in this invention;
[0042] Figure 8 This is a schematic diagram of the left and right axis concrete column ring structure described in this invention. Detailed Implementation
[0043] The technical solution of the present invention will be further described below with reference to the accompanying drawings.
[0044] The present invention discloses a kiln tail reinforcement structure, as shown in the figure, comprising an original kiln tail frame, a first floor, and a second floor. The original kiln tail frame includes a left foundation 101, a middle foundation 102, a right foundation 103, a left-axis concrete column 3, a middle-axis concrete column 4, a right-axis concrete column 5, a left-axis steel column 6, a middle-axis steel column 7, and a right-axis steel column 8. A first-floor left-side concrete beam 9 is provided between the left-axis concrete column 3 and the middle-axis concrete column 4. A first-floor right-side concrete beam 10 is provided between the middle-axis concrete column 4 and the right-axis concrete column 5. A second-floor left-side steel beam 26 is provided between the left-axis steel column 6 and the middle-axis steel column 7. A second-floor right-side steel beam 27 is provided between the middle-axis steel column 7 and the right-axis steel column 8.
[0045] Several new foundations 2 are symmetrically arranged on the outer sides of the left foundation 101 and the right foundation 103. Each new foundation 2 is connected to a steel support structure at its top. The steel support structure includes a vertically arranged lower steel pipe 11 and an obliquely arranged upper steel pipe 12. The bottom end of the lower steel pipe 11 is fixedly connected to the top of the new foundation 2 via a first hinge support 13, and its top end is fixedly connected to the bottom of the upper steel pipe 12 via a second hinge support 14. Second node plates are symmetrically welded to the outer sides of the left axis steel column 6 and the right axis steel column 8 at the top of the upper steel pipe 12. Third hinge supports 15 are installed on the second node plates. Above, the second node plate node is welded with reinforcing ribs. The left axis concrete column 3, the middle axis concrete column 4 and the right axis concrete column 5 are respectively provided with a first fixing part, a second fixing part and a third fixing part at the contact parts with the upper surface of the first floor. The left axis steel column 6 and the right axis steel column 8 are provided with a fourth fixing part and a fifth fixing part at the contact parts with the lower surface of the second floor. A first set of prestressed steel strands 22 is provided between the second fixing part and the fourth and fifth fixing parts. A second set of prestressed steel strands 23 is provided between the first fixing part, the third fixing part and the lower steel pipe 11 parallel to them.
[0046] The second fixing part includes a first steel plate 18 symmetrically embedded on the front and rear sides of the intermediate axis concrete column 4 via chemical anchors and steel plates. Several first channel steels 29 are welded transversely on the first steel plate 18. Second steel plates 28 are welded to both ends of the first channel steels 29 respectively. Several holes matching the number of steel strands are opened on the second steel plate 28. The inner side of the second steel plate 28 is welded with a first tensioning end clamp 19 for tensioning the first group of prestressed steel strands 22 according to the position of the holes. The fourth and fifth fixing parts are both welded with a first node plate 20. The first anchoring end clamp 21 for anchoring the first group of prestressed steel strands 22 is welded on the first node plate 20. The first anchoring end clamp 21 faces the second fixing part.
[0047] Both the first and third fixing parts are equipped with a three-sided hoop 16 welded from steel plates and second channel steel 31. The opening of the hoop 16 faces outward from the frame. A third steel plate 30 is welded to the open end of the hoop 16. Several holes matching the number of steel strands are opened on the third steel plate 30. The second tensioning end clamp 17 for tensioning the second group of prestressed steel strands 23 is welded to the inner side of the third steel plate 30 according to the position of the holes. The bottom plate of the second hinge support 14 is flush with the top surface of the hoop 16. A fastener 24 is provided at the top of the lower steel pipe 11 close to the second hinge support 14. A second anchoring end clamp 25 for anchoring the second group of prestressed steel strands 23 is welded to the fastener 24. The height of the second anchoring end clamp 25 is the same as the height of the second tensioning end clamp 17.
[0048] The present invention provides a method for reinforcing the kiln tail layer, comprising the following reinforcement steps:
[0049] S1: As attached Figure 1-2As shown, based on the increased load of the original kiln tail frame, the dimensions of the bottom frame, the available space around the kiln tail frame, and the bearing capacity of the foundation, the location and dimensions of the new foundation 2, the cross section of the steel support structure, and the tension parameters of the first set of prestressed steel strands 22 and the second set of prestressed steel strands 23 are determined by modeling and calculation using general structural design software.
[0050] S2: Construct a new foundation 2 outside the left foundation 101 and right foundation 103 of the original kiln tail frame. Install the first hinge support 13 on the pre-embedded anchor bolts on the top of the new foundation 2 to fix the lower steel pipe 11.
[0051] S3: On the first floor, near the height of the first floor, chemical anchors and steel plates are used to symmetrically install the first steel plate 18 on both the front and rear sides of the intermediate axis concrete column 4. Several first channel steels 29 are horizontally welded on the first steel plate 18. Second steel plates 28 are welded to both ends of the first channel steels 29 respectively. Several holes matching the number of steel strands are opened on the second steel plate 28. The first tensioning end clamp 19 of the first set of prestressed steel strands 22 is welded to the inside of the second steel plate 28 according to the position of the holes. On the outside of the left axis concrete column 3 and the outside of the right axis concrete column 5, at the height of the first floor, a three-sided hoop 16 is welded using steel plates and second channel steels 31. The opening of the hoop 16 faces the outside of the frame. A third steel plate 30 is welded to the open end of the hoop 16. Several holes matching the number of steel strands are opened on the third steel plate 30. The second tensioning end clamp 17 of the second set of prestressed steel strands 23 is welded to the inside of the third steel plate 30 according to the position of the holes.
[0052] S4: Weld the first node plate 20 to the bottom of the steel beam 26 on the left side of the second floor and to the right of the steel column 6 on the left axis. Weld the first set of prestressed steel strand first anchorage end clamps 21 to the first node plate 20. The opening of the first anchorage end clamps 21 faces the contact part between the first floor and the intermediate axis concrete column 4 on the corresponding side. On the other side, at the bottom of the steel beam 27 on the right side and to the left of the steel column 8 on the right axis, install the node plate 20 and the prestressed steel strand anchorage end clamps 21 symmetrically. The installation method is the same as that on the steel column on the left axis.
[0053] S5: At the height of the second floor of the kiln tail frame, the second node plates are symmetrically welded to the outer sides of the left and right axis steel columns, the third hinge support 15 is installed, and stiffening ribs are welded to the beam-column joint where the second node plate is located for reinforcement.
[0054] S1-S5 can be performed simultaneously.
[0055] S6: The steel supports on the outside of the symmetrically installed frame are connected to the bottom of the lower steel pipe 11 and the hinge support 13 at the top of the newly built foundation 2 on the outside of the frame. The upper steel pipe 12 is installed obliquely and the top of the upper steel pipe 12 is connected to the third hinge support 15 on the outside of the left and right columns of the second floor. The top of the lower steel pipe 11 and the bottom of the upper steel pipe 12 are connected through the second hinge support 14. The bottom plate of the second hinge support 14 is flush with the top surface of the hoop 16. The fastener 24 is installed at the top of the lower steel pipe 11 close to the second hinge support 14, and the second anchoring end clamp 25 of the second set of prestressed steel strands 23 is welded on the fastener 24. The height of the second anchoring end clamp 25 is the same as the height of the second tensioning end clamp 17.
[0056] S7: On the frame, with the central axis of the intermediate foundation 102 as the axis of symmetry, two sets of first prestressed steel strands 22 and two sets of second prestressed steel strands 23 are symmetrically installed. One end of the second set of prestressed steel strands 23 is anchored by the second anchoring end clamp 25, and the other end is fixed on the second tensioning end clamp 17; one end of the first set of prestressed steel strands 22 is anchored by the first anchoring end clamp 21, and the other end is installed on the first tensioning end clamp 19;
[0057] S8: Install tensioning equipment on the first floor to tension the first group of prestressed steel strands 22 and the second group of prestressed steel strands 23 respectively. Tension the second group of prestressed steel strands 23 first, and anchor them after reaching the designed tension force. Transfer all the additional loads on the original frame due to the addition of the floor from the left-side foundation 101 to the newly added foundation 2 on the outside of the frame. A simplified diagram of the force flow direction is shown below. Figure 5 As shown, the first set of prestressed steel strands 22 are then tensioned to the design required tension force and then anchored. The increased load on the intermediate shaft foundation 102 due to the addition of layers is transferred to the left shaft foundation 101 and the right shaft foundation 103. A simplified diagram of the force flow direction is attached. Figure 6 As shown, after tensioning is completed, it is inspected and accepted. Once it is confirmed that there are no problems, the excess part of the steel strand can be cut off, the tensioning equipment can be removed, and the reinforcement can be completed.
Claims
1. A kiln tail reinforcement structure, comprising an original kiln tail frame, a first floor and a second floor, wherein the original kiln tail frame comprises a left foundation (101), a middle foundation (102), a right foundation (103), a left-axis concrete column (3), a middle-axis concrete column (4), a right-axis concrete column (5), a left-axis steel column (6), a middle-axis steel column (7), and a right-axis steel column (8), wherein a first-floor left concrete beam (9) is provided between the left-axis concrete column (3) and the middle-axis concrete column (4), a first-floor right concrete beam (10) is provided between the middle-axis concrete column (4) and the right-axis concrete column (5), a second-floor left steel beam (26) is provided between the left-axis steel column (6) and the middle-axis steel column (7), and a second-floor right steel beam (27) is provided between the middle-axis steel column (7) and the right-axis steel column (8); characterized in that It also includes several new foundations (2) symmetrically arranged outside the left foundation (101) and the right foundation (103). The top of each new foundation (2) is connected to a steel support structure, which includes a vertically arranged lower steel pipe (11) and an obliquely arranged upper steel pipe (12). The bottom end of the lower steel pipe (11) is fixedly connected to the top of the new foundation (2), and the top end is fixedly connected to the bottom of the upper steel pipe (12). The top of the upper steel pipe (12) is fixedly connected to the outside of the left axis steel column (6) and the right axis steel column (8). The left axis concrete The soil column (3), the intermediate axis concrete column (4) and the right axis concrete column (5) are respectively provided with a first fixing part, a second fixing part and a third fixing part at the contact parts with the upper surface of the first floor. The left axis steel column (6) and the right axis steel column (8) are provided with a fourth fixing part and a fifth fixing part at the contact parts with the lower surface of the second floor. A first set of prestressed steel strands (22) is provided between the second fixing part and the fourth and fifth fixing parts. A second set of prestressed steel strands (23) is provided between the first fixing part, the third fixing part and the lower steel pipe (11) parallel to them. The second fixing part includes a first steel plate (18) symmetrically embedded on the front and rear sides of the intermediate shaft concrete column (4). Several first channel steels (29) are welded transversely on the first steel plate (18). Second steel plates (28) are welded to both ends of the first channel steels (29). Several holes matching the number of steel strands are opened on the second steel plate (28). A first tensioning end clamp (19) for tensioning the first group of prestressed steel strands (22) is welded to the inner side of the second steel plate (28) according to the position of the holes. The fourth fixing part and the fifth fixing part are both welded with a first node plate (20). A first anchoring end clamp (21) for anchoring the first group of prestressed steel strands (22) is welded to the first node plate (20). The newly added foundation (2) is provided with a first hinge support (13) at the top. The lower steel pipe (11) is hinged to the newly added foundation (2) through the first hinge support (13). The lower steel pipe (11) is provided with a second hinge support (14) at the top. The upper steel pipe (12) is hinged to the lower steel pipe (11) at the bottom through the second hinge support (14). The left and right steel beams of the second floor are provided with a third hinge support (15) on the outside. The top of the upper steel pipe (12) is hinged to the third hinge support (15).
2. The kiln tail reinforcement structure according to claim 1, characterized in that, Both the first and third fixing parts are provided with a three-sided ring hoop (16) welded from a steel plate and a second channel steel (31). The opening of the ring hoop (16) faces the outside of the frame. A third steel plate (30) is welded to the end of the opening side of the ring hoop (16). Several holes matching the number of steel strands are opened on the third steel plate (30). The second tensioning end clamp (17) for tensioning the second group of prestressed steel strands (23) is welded to the inside of the third steel plate (30) according to the position of the holes. The bottom plate of the second hinge support (14) is flush with the top surface of the ring hoop (16). The top of the lower steel pipe (11) is provided with a fastener (24) close to the position of the second hinge support (14). A second anchoring end clamp (25) for anchoring the second group of prestressed steel strands (23) is welded on the fastener (24). The height of the second anchoring end clamp (25) is the same as the height of the second tensioning end clamp (17).
3. The kiln tail reinforcement structure according to claim 1, characterized in that, The second node plate is symmetrically welded to the outer side of the steel beams on the left and right sides of the second floor. The third hinge support (15) is installed on the second node plate, and reinforcing ribs are welded to the nodes of the second node plate.
4. The kiln tail reinforcement structure according to claim 1, characterized in that, The first steel plate (18) is pre-embedded on the front and rear sides of the intermediate shaft concrete column (4) by chemical anchors and steel plate installation.
5. The kiln tail reinforcement structure according to claim 1, characterized in that, The first anchoring end clamp (21) faces the second fixing part.
6. The kiln tail reinforcement structure according to claim 1, characterized in that, The first group of prestressed steel strands (22) and the second group of prestressed steel strands (23) each have two groups.
7. A method for reinforcing the kiln tail layer, characterized in that, The reinforcement steps include the following: S1: Based on the increased load of the original kiln tail frame, the size of the bottom frame, the available space around the kiln tail frame, and the bearing capacity of the foundation, use general structural design software to model and calculate to determine the location and size of the new foundation (2), the cross section of the steel support structure, and the tension parameters of the first set of prestressed steel strands (22) and the second set of prestressed steel strands (23); S2: Construct a new foundation (2) on the outside of the left foundation (101) and right foundation (103) of the original kiln tail frame. Install the first hinge support (13) on the pre-embedded anchor bolts on the top of the new foundation (2) to fix the lower steel pipe (11). S3: On the first floor, near the height of the first floor, chemical anchors and steel plates are used to symmetrically install the first steel plate (18) on both the front and back sides of the intermediate axis concrete column (4). Several first channel steels (29) are welded horizontally on the first steel plate (18). Second steel plates (28) are welded to both ends of the first channel steels (29). Several holes matching the number of steel strands are opened on the second steel plate (28). The first set of prestressed steel strands (22) is welded to the inside of the second steel plate (28) according to the position of the holes. Tensioning end clamp (19); On the outside of the left axis concrete column (3) and the outside of the right axis concrete column (5), at a height level with the first floor, a three-sided hoop (16) is welded using steel plate and second channel steel (31). The hoop (16) opens to the outside of the frame. A third steel plate (30) is welded to the open end of the hoop (16). Several holes matching the number of steel strands are opened on the third steel plate (30). The second tensioning end clamp (17) of the second set of prestressed steel strands (23) is welded to the inside of the third steel plate (30) according to the position of the holes. S4: At the bottom of the steel beam (26) on the left side of the second floor and the right side of the steel column (6) on the left side of the second floor, weld the first node plate (20), and weld the first anchoring end clamp (21) of the first set of prestressed steel strands (22) on the first node plate (20). The opening direction of the first anchoring end clamp (21) is towards the contact part between the first floor and the intermediate shaft concrete column (4) on the corresponding side. S5: At the height of the second floor of the kiln tail frame, the second node plates are symmetrically welded to the outside of the left and right axis steel columns, the third hinge shaft support (15) is installed, and stiffening ribs are welded to the beam-column joint where the second node plate is located for reinforcement. S6: The steel supports on the outside of the frame are symmetrically installed. The bottom end of the lower steel pipe (11) is connected to the hinge support (13) at the top of the newly built foundation (2) on the outside of the frame. The upper steel pipe (12) is installed obliquely and the top end is connected to the third hinge support (15) on the outside of the left and right columns of the second floor. The top end of the lower steel pipe (11) and the bottom end of the upper steel pipe (12) are connected through the second hinge support (14). The bottom plate height of the second hinge support (14) is flush with the top surface of the hoop (16). A fastener (24) is installed at the top of the lower steel pipe (11) close to the second hinge support (14), and the second anchoring end clamp (25) of the second set of prestressed steel strands (23) is welded on the fastener (24). The height of the second anchoring end clamp (25) is consistent with the height of the second tensioning end clamp (17). S7: On the frame, with the central axis of the intermediate foundation (102) as the axis of symmetry, two sets of first prestressed steel strands (22) and two sets of second prestressed steel strands (23) are symmetrically installed. One end of the second set of prestressed steel strands (23) is anchored by the second anchoring end clamp (25), and the other end is fixed on the second tensioning end clamp (17); one end of the first set of prestressed steel strands (22) is anchored by the first anchoring end clamp (21), and the other end is installed on the first tensioning end clamp (19); S8: Install tensioning equipment on the first floor and tension the first group of prestressed steel strands (22) and the second group of prestressed steel strands (23) respectively. After reaching the tension force required by the design, anchor them. After tensioning is completed, inspect and accept them. Once it is confirmed that there are no errors, cut off the excess part of the steel strands, remove the tensioning equipment, and complete the reinforcement.
8. The method for reinforcing the kiln tail layer according to claim 7, characterized in that, The tensioning steps of the two sets of steel strands in S8 are as follows: First, the second set of prestressed steel strands (23) are tensioned and anchored after reaching the required tension force. All the loads that the original frame will increase due to the addition of the layer are transferred from the left axial foundation (101) to the newly added foundation (2) on the outside of the frame. Then, the first set of prestressed steel strands (22) is tensioned and anchored after reaching the required tension force. The loads that the middle axial foundation (102) will increase due to the addition of the layer are transferred to the left axial foundation (101) and the right axial foundation (103).