Stair surface layer old-imitation repairing process and application thereof

Abstract

The invention belongs to the technical field of building civil engineering, and particularly relates to a stair surface layer distressing repairing process and application thereof. The repairing process comprises the following steps: (1) chiseling and wetting an original stair surface layer, spraying UHPC (Ultra High Performance Concrete), erecting a mold, pouring distressed cement mortar into the mold, leveling, finishing and troweling, and setting a contrast experiment group with the same treatment in the same environment; the vintage cement mortar comprises ordinary Portland cement yellow sand and water; (2) after an initial setting state is achieved, the mold is dismantled, and a passivating agent is sprayed; (3) cleaning for at least two times after spraying a passivating agent, airing until the humidity is within 10%, spraying a sealing curing agent, and drying and forming; the stair surface layer comprises a kicking surface and / or a tread surface. By means of the specific repairing process, the phenomena of hollowing and cracking of the repaired stair layer can be avoided, the antique effect is durable, the phenomena of color fading and falling off are prone to occurring, and the repaired antique stair layer can be used for a long time.

Description

Technical Field

[0001] The invention belongs to the technical field of building civil engineering, and particularly relates to a stair surface imitation repair process and application thereof. Background Art

[0002] The old staircase uses mortar as the tread. During the repair, the plaster layer at the interface between the old and new is prone to hollowing and cracking. The repair of the old staircase not only considers preserving historical traces, but also ensures that it is not prone to hollowing and cracking even if stepped on frequently, so as to extend the service life. The traditional method uses traditional interface agents combined with plastering and color-matching paint for antique repair, but this method has limited improvement on hollowing and cracking, and the antique effect is poor in durability and is prone to fading and falling off. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the limited improvement of the hollowing and cracking phenomena in the existing old stair repair methods, and the poor durability of the antique effect, and the defects of fading and falling off easily occur, thereby providing a stair surface antique repair process and its application.

[0004] The present invention provides a stair surface imitation repair process, comprising the following steps:

[0005] 1) Roughen the original stair surface, moisten it, spray UHPC powder, and then set up a mold to fix it. Pour the antique cement mortar into the mold to level it, and then smooth it. At the same time, set up a comparative experimental group with the same treatment under the same environment;

[0006] The raw materials of the antique cement mortar include, by weight: 0.6-1.5 parts of ordinary Portland cement, 1.5-3.5 parts of yellow sand and 0.2-0.6 parts of water;

[0007] 2) Testing the antique cement mortar surface of the comparative experimental group described in step 1), removing the mold after confirming that it has reached the initial setting state, and then spraying a passivating agent on the smoothed stair surface;

[0008] 3) After spraying the passivating agent, clean it at least twice, dry it until the humidity reaches less than 10%, spray the sealing curing agent on the dried stair surface, and dry it into shape.

[0009] The stair surface layer includes a riser and a tread.

[0010] The UHPC powder described in the present invention is a special concrete with ultra-high strength, ultra-low water absorption, ultra-durability and erosion resistance, ultra-high performance concrete, referred to as UHPC (Ultra-High Performance Concrete). Its compressive strength is greater than 120MPa. UHPC powder can be obtained commercially, for example, UHPC ultra-high performance concrete purchased from Changsha Xingju Building Materials Technology Co., Ltd., brand: Xingju Building Materials, implementation standard: T / CECS10107-2020; or UHPC ultra-high performance concrete purchased from Gansu Kaihengda New Materials Technology Co., Ltd., brand: Kaihengda.

[0011] The present invention does not impose any specific limitation on the nature of the supporting mold, as long as it can achieve the function of fixing the stair surface layer. For example, an L-shaped mold can be selected.

[0012] Preferably, the spraying pressure of the UHPC powder in step 1) is 0.2-0.6Mpa;

[0013] The spraying thickness of the sprayed UHPC powder is 3-5 mm.

[0014] Preferably, the preparation step of the antique cement mortar in step 1) comprises: stirring and mixing ordinary Portland cement and yellow sand, and then adding water and stirring and mixing;

[0015] The antique cement mortar in step 1) is poured into the mold to level the thickness of not less than 1 cm;

[0016] The stair surface layer includes risers and / or treads.

[0017] Optionally, add water and stir to mix for 30-60 minutes;

[0018] The thickness of the antique cement mortar poured into the mold for leveling can be selected according to the actual height of the stairs, but it needs to be at least not less than 1 cm. At this thickness, it can ensure that the surface layer of the antique repaired stairs is not easy to fade or fall off and can be used for a long time.

[0019] Preferably, the yellow sand in step 1) is 40-60 mesh yellow sand;

[0020] The roughening process has a roughening depth of 3-5 mm.

[0021] Preferably, in step 2), the needle penetration method is used to detect the distressed cement mortar surface of the comparative experimental group, and the penetration depth is 0.3mm-0.5mm, which means that the initial setting state is reached;

[0022] The mold is removed 10-20 minutes after the antique cement mortar surface of the comparative experimental group described in step 1) reaches the initial setting state.

[0023] Preferably, the spraying thickness of the passivating agent in step 2) is 0.05-0.2 mm.

[0024] Preferably, step 3) specifically includes: performing a first cleaning on the cement mortar surface 0.5-1h after spraying the passivating agent, performing a second cleaning 0.5-1h after the first cleaning, and drying it. When the humidity reaches less than 10%, spraying a sealing curing agent on the dried stair surface, drying it into shape, and removing the mold.

[0025] Preferably, in step 3), the cleaning agent for the first cleaning is selected from water;

[0026] The cleaning agent of the second cleaning is selected from water.

[0027] Preferably, in step 3), the dried stair surface is sprayed with a sealing curing agent 2-3 times and then naturally dried to form.

[0028] The present invention does not impose any specific restrictions on the specific selection of ordinary silicate cement, passivating agent, and sealing curing agent, as long as the corresponding purpose can be achieved, and all of them can be obtained commercially.

[0029] For example, it can be selected that the ordinary Portland cement is selected from the P.O42.5 ordinary Portland cement purchased from Hunan Pingtang Nanfang Cement Co., Ltd.;

[0030] For example, the passivating agent may be selected from Surface passivation agent, purchased from Beijing Shenglong New Material Technology Co., Ltd., brand: Kelaibi, model: SD;

[0031] For example, the sealing curing agent can be selected from the sealing curing agent of the German BASF model MASTERTOPCC700.

[0032] The present invention provides an application of the above-mentioned stair surface imitation repair process in the repair of old stairs.

[0033] The technical solution of the present invention has the following advantages:

[0034] The invention provides a process for repairing the surface of stairs in an antique manner, comprising the following steps: 1) roughening the original surface of the stairs, wetting it, spraying UHPC powder, then setting up a mold to fix it, pouring the antique cement mortar into the mold for leveling, and then smoothing it, and setting a comparative experimental group with the same treatment under the same environment; the antique cement mortar, in parts by weight, comprises: 1 part of ordinary Portland cement, 2 parts of yellow sand and 0.42 parts of water; 2) testing the antique cement mortar surface of the comparative experimental group described in step 1), removing the mold after confirming that it reaches the initial setting state, and then spraying a passivator on the surface of the stair surface that has been smoothed; 3) washing at least twice after spraying the passivator, drying until the humidity reaches less than 10%, spraying a sealing curing agent on the dried stair surface, and drying to form. The present invention can not only increase the physical and mechanical bite force by using UHPC (ultra-high performance concrete) powder, but also its chemical components can react chemically with the treated surface, increase the surface roughness from the physical and chemical double aspects, improve the bonding strength between the antique cement mortar and the base layer, coordinate the specific antique cement mortar and other steps to cooperate with each other, and improve the bonding strength of the stair surface as a whole, avoiding hollowing and cracking; at the same time, the natural color of yellow sand and ordinary silicate cement itself is used, and no other pigments or color pastes are added to adjust the color, and the antique cement mortar formed, in the specific antique cement mortar and other steps, cooperate with each other, the color tone of the repaired antique stair surface is naturally not easy to fade, not easy to fall off, and has strong durability. The specific application of UHPC and the specific antique cement mortar of the present invention can avoid the occurrence of hollowing and cracking on the repaired stair surface, and the antique effect is durable, and it is easy to fade and fall off, and the repaired antique stair surface can be used for a long time. DETAILED DESCRIPTION

[0035] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0036] If no specific experimental steps or conditions are specified in the examples, the conventional experimental steps or conditions described in the literature in the field can be used. If no manufacturer is specified for the reagents or instruments used, they are all conventional reagent products that can be obtained commercially.

[0037] The UHPC powder used in the embodiments and comparative examples of the present invention was purchased from the UHPC ultra-high performance concrete of Changsha Xingju Building Materials Technology Co., Ltd., brand: Xingju Building Materials, implementation standard: T / CECS 10107-2020; P.O42.5 ordinary Portland cement was purchased from the distributor: Hunan Xindingli New Materials Technology Co., Ltd., whose manufacturer: Hunan Pingtang Nanfang Cement Co., Ltd.; the passivator was purchased from Beijing Shenglong New Materials Technology Co., Ltd., brand: selected from Surface passivation agent, model: SD; sealing curing agent purchased from distributor: Dongguan Huazhiyuan Chemical Co., Ltd., manufacturer: BASF, Germany, model MASTERTOPCC700;

[0038] The vinyl acetate-ethylene copolymer emulsion interface agent used in the comparative example of the present invention was purchased from Nanjing Xinyi Synthetic Technology Co., Ltd., model LE410; the epoxy resin interface agent was purchased from Beijing Dinggu Weiye Engineering Materials Co., Ltd., product model J-302.

[0039] Example 1

[0040] This embodiment provides a stair surface repair process, including the following steps:

[0041] 1) The risers and treads of the original stair surface were roughened, moistened, and sprayed with UHPC powder, wherein the roughening depth was 4 mm, not exceeding 10% of the original stair thickness, the spraying pressure of the UHPC powder was 0.4 MPa, and the spraying thickness of the UHPC powder was 4 mm. Then, an L-shaped stainless steel mold was set up to fix the stair surface, and the antique cement mortar was poured into the mold for leveling, and then smoothed. At the same time, a comparative experimental group with the same treatment was set up under the same environment;

[0042] The raw materials of the antique cement mortar include, by weight, 1 part of ordinary Portland cement, 2 parts of 40-60 mesh yellow sand and 0.42 parts of water; the preparation steps of the antique cement mortar include: mixing the ordinary Portland cement and the yellow sand by weight, and then adding the corresponding weight part of water and stirring and mixing;

[0043] 2) When the needle penetration method is used to penetrate the antique cement mortar layer of the comparative experimental group described in step 1), the penetration depth is 0.4 mm, which means that the initial setting state is reached. After reaching the initial setting state, the mold is removed 10 minutes later, and then a passivating agent with a thickness of 0.1 mm is sprayed on the surface of the stair surface that has been smoothed and troweled;

[0044] 3) Clean the cement mortar surface with water for the first time 0.7 hours after spraying the passivator, and clean it with water for the second time 0.7 hours after the first cleaning. Let it dry. When the humidity reaches 9%, spray the sealing and curing agent on the dried stair surface twice, let it dry and form, and complete the antique repair of the stair surface.

[0045] Example 2

[0046] This embodiment provides a stair surface repair process, including the following steps:

[0047] 1) The risers and treads of the original stair surface were roughened, moistened, and sprayed with UHPC powder, wherein the roughening depth was 3 mm, not exceeding 10% of the original stair thickness, the spraying pressure of the UHPC powder was 0.6 MPa, and the spraying thickness of the UHPC powder was 5 mm. Then, an L-shaped stainless steel mold was set up to fix the stair surface, and the antique cement mortar was poured into the mold for leveling, and then smoothed. At the same time, a comparative experimental group with the same treatment was set up under the same environment;

[0048] The raw materials of the antique cement mortar include, by weight, 0.6 parts of ordinary Portland cement, 1.5 parts of 40-60 mesh yellow sand and 0.2 parts of water; the preparation steps of the antique cement mortar include: mixing the ordinary Portland cement and the yellow sand by weight, and then adding the corresponding weight of water and stirring and mixing;

[0049] 2) When the needle penetration method is used to penetrate the antique cement mortar layer of the comparative experimental group described in step 1), the penetration depth is 0.4 mm, which means that the initial setting state is reached. After reaching the initial setting state, the mold is removed 15 minutes later, and then a passivating agent with a thickness of 0.1 mm is sprayed on the surface of the stair surface that has been smoothed and troweled;

[0050] 3) 1 hour after spraying the passivating agent, clean the cement mortar surface with water for the first time, and 1 hour after the first cleaning, clean it with water for the second time, and let it dry. When the humidity reaches 9%, spray the sealing and curing agent on the dried stair surface for 3 times, let it dry and form, and complete the antique repair of the stair surface.

[0051] Example 3

[0052] This embodiment provides a stair surface repair process, including the following steps:

[0053] 1) The risers and treads of the original stair surface were roughened, moistened, and sprayed with UHPC powder, wherein the roughening depth was 3 mm, not exceeding 10% of the original stair thickness, the spraying pressure of the UHPC powder was 0.2 MPa, and the spraying thickness of the UHPC powder was 3 mm. Then, an L-shaped stainless steel mold was set up to fix the stair surface, and the antique cement mortar was poured into the mold for leveling, and then smoothed. At the same time, a comparative experimental group with the same treatment was set up under the same environment;

[0054] The raw materials of the antique cement mortar include, by weight, 1.5 parts of ordinary Portland cement, 3.5 parts of 40-60 mesh yellow sand and 0.6 parts of water; the preparation steps of the antique cement mortar include: mixing the ordinary Portland cement and the yellow sand by weight, and then adding the corresponding weight of water and stirring and mixing;

[0055] 2) When the needle penetration method is used to penetrate the antique cement mortar layer of the comparative experimental group described in step 1), the penetration depth is 0.4 mm, which means that the initial setting state is reached. After reaching the initial setting state, the mold is removed 10 minutes later, and then a passivating agent with a thickness of 0.2 mm is sprayed on the surface of the stair surface that has been smoothed and troweled;

[0056] 3) Clean the cement mortar surface with water for the first time 0.5 hours after spraying the passivator, and clean it with water for the second time 0.5 hours after the first cleaning. Let it dry. When the humidity reaches 9%, spray the sealing and curing agent on the dried stair surface twice, let it dry and form, and complete the antique repair of the stair surface.

[0057] Comparative Example 1

[0058] The present comparative example provides a process for repairing the surface of stairs in an antique manner, which differs from Example 1 only in that in step 1), the risers and treads of the original stair surface are roughened, moistened, and a vinyl acetate-ethylene copolymer emulsion interface agent is rolled on, wherein the roughening depth is 4 mm, which does not exceed 10% of the original thickness of the stairs, and the thickness of the vinyl acetate-ethylene copolymer emulsion interface agent is rolled on to be 1 mm, and then an L-shaped stainless steel mold is set up to fix the stair surface, and antique cement mortar is poured into the mold for leveling, and then smoothed and polished. At the same time, a comparative experimental group with the same treatment is set up under the same environment.

[0059] Comparative Example 2

[0060] The present comparative example provides a process for repairing the surface of stairs in an antique manner, which differs from Example 1 only in that in step 1), the risers and treads of the original stair surface are roughened, moistened, and epoxy resin interface agent is rolled on, wherein the roughening depth is 4 mm, which does not exceed 10% of the original thickness of the stairs, and the thickness of the epoxy resin interface agent is rolled on to be 1 mm, and then an L-shaped stainless steel mold is set up to fix the stair surface, and antique cement mortar is poured into the mold for leveling, and then smoothed and polished. At the same time, a comparative experimental group with the same treatment is set up under the same environment.

[0061] Comparative Example 3

[0062] This comparative example provides a process for repairing the antiqued surface of stairs, which differs from Example 1 only in that the antiqued cement mortar in step 1) comprises, by weight, 0.6 parts of ordinary Portland cement, 4 parts of 40-60 mesh yellow sand and 0.6 parts of water.

[0063] Comparative Example 4

[0064] This comparative example provides a stair surface imitation repair process, including the following steps:

[0065] 1) 9501 extra black water-based color paste, 9401 ordinary white water-based color paste and iron yellow water-based color paste were mixed and prepared in a mass ratio of 1:1:2 to obtain antique color paste. 9501 extra black water-based color paste, 9401 ordinary white water-based color paste and iron yellow water-based color paste (No.: S-8810) were purchased from Wenling Caiyuan Pigment Co., Ltd.;

[0066] 2) Clean the surface of the stair surface, and continuously apply the antique color paste obtained in step 1) three times on the original wall plaster layer to form a repaired antique color paste stair surface layer.

[0067] Test Example 1

[0068] The stair surfaces repaired by the stair surface antique repair process of Examples 1-3 and Comparative Examples 1-4 were subjected to a mortar bonding strength pull-out test to detect the bonding strength between the layers. The higher the bonding strength, the less likely it is to produce hollowing and cracking. Specific testing method: 100mm×100mm square cut blocks were cut on the stair surfaces repaired by the stair surface antique repair process of Examples 1-3 and Comparative Examples 1-4, and the cut depth reached the depth of the roughening treatment of the original stair surface. The cut depth of the stair surface repaired in Comparative Example 4 was kept consistent with that in Example 1. Six 100mm×100mm square cut blocks were cut on the stair surface repaired by each repair method. Remove stains from the square cut block and the top drawing plate of the LB-6S mortar bonding strength drawing instrument and keep it dry. Use an adhesive with a bonding strength greater than 3.0MPa to bond the top drawing plate of the LB-6S mortar bonding strength drawing instrument to the tested square cut block. After the adhesive is completely cured, start the drawing test until the square cut block breaks and is pulled out. Record the bonding strength test value of the LB-6S mortar bonding strength drawing instrument when it is pulled out, as well as the fracture position. The fracture position is recorded as A at the connection between the antique cement mortar surface layer and the old stair surface layer, the fracture position is recorded as B at the antique cement mortar layer, and the fracture position is recorded as C at the connection between the antique color paste and the old stair surface layer. The test results are shown in Table 1.

[0069] Table 1

[0070]

[0071]

[0072] As can be seen from Table 1, the bonding strength of the stair surface repaired by the specific repair process of the present invention can reach 0.4Mpa-0.5Mpa, which is higher than the bonding strength of the stair surface repaired by the repair process of the comparison example. This shows that the stair surface repaired by the specific repair process of the present invention is not prone to hollowing and cracking, and has good long-term usability.

[0073] Test Example 2

[0074] A friction simulation experiment was carried out on the stair surfaces repaired by the antique repair process of the stair surface layer of Examples 1-3 and Comparative Example 4, respectively. The same batch of solid clay bricks from the same manufacturer were used to rub the repaired stair surfaces back and forth under a pressure of 0.3 MPa to simulate the trampling and wear of the stair surfaces by the crowd. The specifications of the solid clay bricks were 240 mm × 115 mm × 53 mm, and the reciprocating friction area was 240 mm × 500 mm. The friction strength generated by the same batch of solid clay bricks from the same manufacturer under a pressure of 0.3 MPa was considered to be consistent. The friction was performed for 1 minute, with an interval of 2 minutes. The experiment was terminated after 100 reciprocating cycles, and the final surface shedding area rate was recorded. The results are shown in Table 2.

[0075] Table 2

[0076]

[0077]

[0078] It can be seen from Table 2 that the repair process of the embodiment of the present invention can obviously keep the surface layer of the antique stairs from falling off and keep it stable. At the same time, since the repair process of the present invention achieves the antique effect through the color of the yellow sand itself, the color of the yellow sand itself will not fade due to environmental influences.

[0079] In summary, the antique repair process for stair surface of the present invention can avoid hollowing and cracking in the repaired stair surface, and the antique effect is long-lasting and not prone to fading and falling off. The repaired antique stair surface can be used for a long time.

[0080] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A process for repairing the surface of stairs in an antique manner, characterized in that: The steps include: 1) Roughen the original stair surface, moisten it, spray UHPC powder, and then set up a mold to fix it. Pour the antique cement mortar into the mold to level it, and then smooth it. At the same time, set up a comparative experimental group with the same treatment under the same environment; The raw materials of the antique cement mortar include, by weight: 0.6-1.5 parts of ordinary Portland cement, 1.5-3.5 parts of yellow sand and 0.2-0.6 parts of water; 2) Testing the antique cement mortar surface of the comparative experimental group described in step 1), removing the mold after confirming that it has reached the initial setting state, and then spraying a passivating agent on the smoothed stair surface; 3) After spraying the passivating agent, clean it at least twice, dry it until the humidity reaches less than 10%, spray the sealing curing agent on the dried stair surface, and dry it into shape.

2. The staircase surface restoration process according to claim 1 is characterized in that: The spraying pressure of the UHPC powder in step 1) is 0.2-0.6Mpa; The spraying thickness of the sprayed UHPC powder is 3-5 mm.

3. The staircase surface restoration process according to claim 1 or 2, characterized in that: The preparation steps of the antique cement mortar in step 1) include: stirring and mixing ordinary Portland cement and yellow sand, and then adding water and stirring and mixing; The antique cement mortar in step 1) is poured into the mold to level the thickness of not less than 1 cm; The stair surface layer includes risers and / or treads.

4. The process for repairing the stair surface in an antique manner according to any one of claims 1 to 3, characterized in that: The yellow sand in step 1) is 40-60 mesh yellow sand; The roughening process has a roughening depth of 3-5 mm.

5. The process for repairing the stair surface in an antique manner according to any one of claims 1 to 4, characterized in that: In step 2), the needle penetration method is used to detect the antique cement mortar surface of the comparative experimental group. The penetration depth of 0.3mm-0.5mm is considered to have reached the initial setting state.

6. The process for repairing the stair surface in an antique manner according to any one of claims 1 to 5, characterized in that: The spraying thickness of the passivating agent in step 2) is 0.05-0.2 mm.

7. The process for repairing the stair surface in an antique manner according to any one of claims 1 to 6, characterized in that: Step 3) specifically includes: performing a first cleaning on the cement mortar surface 0.5-1h after spraying the passivating agent, performing a second cleaning 0.5-1h after the first cleaning, and drying. When the humidity reaches less than 10%, spraying a sealing curing agent on the dried stair surface, drying and forming, and removing the mold.

8. The staircase surface restoration process according to claim 7 is characterized in that: The cleaning agent of the first cleaning is selected from water; The cleaning agent of the second cleaning is selected from water.

9. The process for repairing the stair surface in an antique manner according to any one of claims 1 to 8, characterized in that: In step 3), spray the dried stair surface with sealing curing agent 2-3 times and let it dry naturally to form.

10. Application of the stair surface antique repair process described in any one of claims 1 to 9 in the repair of old stairs.

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