Stone pavement structure with high shear resistance and construction method thereof

Abstract

The invention relates to a slate pavement structure with high shear resistance and a construction method of the slate pavement structure. The slate pavement structure comprises a slate surface layer, a mortar cushion layer, a cement concrete leveling layer and a subbase layer which are sequentially arranged from top to bottom, the stone slab surface layer consists of at least two stone slab blocks; the adjacent stone plate blocks are bonded through a bonding layer; the bonding layer is a modified UHPC (Ultra High Performance Concrete) joint filling bonding layer; and high-pressure water jet rough interface treatment is carried out on the joint positions on the two sides of the stone plate blocks. The modified UHPC caulking bonding layer is arranged in the stone slab pavement, so that the stone slab pavement has the advantages of high bonding performance, high shear resistance, good durability, remarkable water resistance and wear resistance and the like, and has the characteristics of high caulking forming speed and simple construction equipment; the problems that in the prior art, after a slate pavement is laid, a joint interface rapidly cracks again and is damaged due to shearing are solved, and the overall performance of the pavement structure of the urban slate pavement can be effectively improved.

Description

Technical Field

[0001] This invention relates to the field of road engineering construction technology, and in particular to a stone slab pavement structure with high shear resistance and its construction method. Background Technology

[0002] Stone pavement is widely used in urban roads, and its structural forms and construction methods are constantly being innovated and improved. However, under the combined effects of traffic load, ambient temperature, and increasing service life, shear failure gradually occurs at the joints between stone slabs, leading to a decline in the bonding performance of the joint filler and interface delamination. This weakens the structural strength to some extent, inducing problems such as pavement subsidence, unevenness, poor drainage, and water accumulation in low-lying areas, severely affecting the service life of stone pavement. Moreover, the joint filler allows surface water to continuously seep into the structure, causing continuous infiltration, exacerbating structural deterioration, and leading to more defects.

[0003] CN108625252A discloses a road paving construction method, including (1) base treatment; (2) leveling and marking lines; (3) trial assembly, according to the pattern, texture and color of the granite, trial assembly is carried out according to the orientation and angle, and the trial-assembled granite is numbered and arranged in two opposite directions; (4) brushing cement mortar and laying mortar bonding layer; (5) trial laying of granite layer, checking whether the mortar surface and the slab are in good fit; (6) laying granite layer; (7) grouting and pressing, after paving, the prepared thin cement grout is poured into the gap between the granite using a small-nozzle grouting pot; (8) curing, after grouting and pressing the gap, the granite is covered with geotextile or clean fine sand for 24 hours, and water is sprayed for curing for no less than 7 days.

[0004] CN117904919A discloses a method for constructing a UHPC thin-layer overlay on old cement concrete pavement. The method includes pre-laying a crack isolation layer on cracks in the old cement concrete pavement for crack isolation construction. After the crack isolation construction is completed, ultra-high performance concrete is laid on the old cement concrete pavement to form a thin-layer overlay. UHPC (Ultra High Performance Concrete) and crack isolation are used as the crack-resistant structure of the thin-layer overlay. The pavement is grooved (along the entire length of the crack or partially grooved) and / or the crack isolation layer to accommodate the shrinkage and expansion of the concrete and prevent the propagation of reflective cracks. At the same time, the pavement grooving helps to avoid buckling instability and failure of the UHPC thin-layer overlay caused by the expansion of adjacent slabs at the crack in the old pavement, as well as the failure of interlayer bonding.

[0005] The existing traditional stone pavement joint filling materials and construction methods, such as increasing the thickness of the joint filling grout and adding a geotextile layer at the bottom of the stone pavement structure during construction, do not produce significant results.

[0006] Therefore, in response to the increasing number of defects in paved stone pavements, there is an urgent need to develop a paved stone pavement with high shear resistance and its construction method. This is of great engineering value for improving the functionality and lifespan of paved stone pavements and achieving efficient construction. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a stone pavement structure with high shear resistance and its construction method. The stone pavement structure of this invention significantly improves overall performance by incorporating a modified UHPC joint filler bonding layer. This modified UHPC joint filler bonding layer not only possesses excellent bonding strength, shear strength, and durability, but also outstanding waterproof and wear-resistant properties. Furthermore, its rapid curing and convenient construction effectively overcome the problem of secondary cracking and shear failure at joints after existing stone pavement installations, thereby significantly enhancing the structural integrity and stability of urban stone pavements.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a stone pavement structure with high shear resistance, the stone pavement structure comprising, from top to bottom, a stone pavement surface layer, a mortar cushion layer, a cement concrete leveling layer and a base layer;

[0010] The stone slab surface layer consists of at least two stone slabs; the adjacent stone slabs are bonded together by an adhesive layer; the adhesive layer is a modified UHPC joint filler adhesive layer; the joints on both sides of the stone slabs are treated with high-pressure water jet roughening interface treatment.

[0011] This invention improves the shear resistance of stone pavement by incorporating a modified UHPC joint filler bonding layer into the pavement structure. The modified ultra-high performance cement-based composite material used in the bonding layer has excellent mechanical properties and impermeability. Furthermore, the incorporation of modified polymers further enhances the interfacial bonding effect, effectively suppressing shear failure at the stone slab joints under cyclic vehicle loads. The modified UHPC joint filler bonding layer exhibits excellent rigidity and crack resistance, and this rigid thin-layer material itself demonstrates excellent long-term service stability and high fatigue life, significantly improving the structural performance of the stone pavement.

[0012] This invention, by employing an interfacial bonding mechanism between a modified UHPC joint filler and the stone slab, effectively decomposes the stress distribution in the joint area, significantly reduces stress concentration effects, and thus effectively delays the formation and propagation of cracks at the joint location. This avoids the problem of early cracking causing damage to the stone slab surface layer and increases the service life of the road structure. Furthermore, the modified UHPC joint filler is highly compatible with the underlying mortar subbase material, exhibiting good integrity and contributing to the overall performance of the structure.

[0013] As a preferred technical solution of the present invention, the stone slabs of the stone slab surface layer are natural marble blocks.

[0014] Preferably, the length of the stone slab is 200~250mm, such as 200mm, 210mm, 220mm, 230mm, 240mm, 250mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0015] Widths range from 200 to 250 mm, such as 200 mm, 210 mm, 220 mm, 230 mm, 240 mm, 250 mm, etc., but are not limited to the listed values. Other unlisted values ​​within the above range also apply.

[0016] The thickness is 180~200mm, such as 180mm, 185mm, 190mm, 195mm, 200mm, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0017] Preferably, the length-to-height ratio of the stone slab is ≥1.0, such as 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0018] As a preferred technical solution of the present invention, the adhesive layer adopts a modified UHPC sealant; the modified polymer doping content of the modified UHPC sealant is ≥0.49%, such as 0.49%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, etc., but is not limited to the listed values, and other unlisted values ​​within the above range are also applicable.

[0019] Preferably, the 28-day compressive strength of the adhesive layer is 110~140MPa, such as 110MPa, 115MPa, 120MPa, 125MPa, 130MPa, 135MPa, 140MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0020] The shear strength of the bond with the slate surface layer is 2.4~3.0MPa, for example 2.4MPa, 2.5MPa, 2.6MPa, 2.7MPa, 2.8MPa, 2.9MPa, 3.0MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0021] The maximum vertical deformation under in-situ shear is ≤0.02mm, such as 0.02mm, 0.019mm, 0.018mm, 0.017mm, 0.016mm, 0.015mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range also apply.

[0022] As a preferred technical solution of the present invention, the 28-day compressive strength of the mortar cushion layer is 35~42MPa, such as 35MPa, 36MPa, 37MPa, 38MPa, 39MPa, 40MPa, 41MPa, 42MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0023] The flexural strength is 4.0~4.8MPa, such as 4.0MPa, 4.1MPa, 4.2MPa, 4.3MPa, 4.4MPa, 4.5MPa, 4.6MPa, 4.7MPa, 4.8MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0024] Preferably, the thickness of the mortar pad is 20~50mm, such as 20mm, 30mm, 40mm, 50mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0025] As a preferred technical solution of the present invention, the cement concrete leveling layer is a C40 fine aggregate concrete layer.

[0026] Preferably, the 28-day compressive strength of the cement concrete leveling layer is 48~55MPa, such as 48MPa, 49MPa, 50MPa, 51MPa, 52MPa, 53MPa, 54MPa, 55MPa, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0027] The flexural strength is 3.8~4.5MPa, such as 3.8MPa, 3.9MPa, 4.0MPa, 4.1MPa, 4.2MPa, 4.3MPa, 4.4MPa, 4.5MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0028] Preferably, the thickness of the cement concrete leveling layer is 40~90mm, such as 40mm, 50mm, 60mm, 70mm, 80mm, 90mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0029] As a preferred technical solution of the present invention, the base layer is a C25 plain concrete layer.

[0030] Preferably, the 28-day compressive strength of the subbase is 30~36MPa, such as 30MPa, 31MPa, 32MPa, 33MPa, 34MPa, 35MPa, 36MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0031] The flexural strength is 2.6~2.9MPa, such as 2.6MPa, 2.7MPa, 2.8MPa, 2.9MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0032] Preferably, the thickness of the base layer is 80~180mm, such as 80mm, 90mm, 100mm, 120mm, 140mm, 160mm, 180mm, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0033] Secondly, the present invention provides a construction method for a stone pavement structure as described in the first aspect, the construction method comprising the following steps:

[0034] (1) A cement concrete leveling layer and a mortar cushion layer are poured sequentially on the upper part of the base layer;

[0035] (2) Remove the mortar bedding layer and design the size of the stone slabs and the paving area;

[0036] (3) The side surface of the stone slab is roughened by high-pressure water jet and then the stone slab is laid.

[0037] (4) The modified UHPC joint filler material is injected into the joint of the adjacent stone slabs using a joint filling device, and after solidification, a modified UHPC joint filling adhesive layer is formed.

[0038] (5) The surface of the stone slab is flamed and cured before traffic is opened to complete the construction of the stone slab pavement structure.

[0039] This invention utilizes modified UHPC joint filler material for casting, combined with high-pressure water jet surface roughening treatment of stone slabs, to form a rigid stone slab surface layer. This fully leverages the performance and advantages of modified UHPC joint filler material, improving the shear resistance and interfacial bonding performance of the stone slab pavement, reducing shear failure at the stone slab joints under load, reducing the debonding phenomenon between adjacent stone slabs in the surface layer, and enhancing the structural and overall strength of the pavement.

[0040] The construction of the stone slab joints of this invention adopts on-site composite material casting and joint filling device to ensure high joint filling quality and construction efficiency, which is conducive to the tight bonding between marble slabs and modified UHPC joint filling material and effectively enhances the interfacial bonding force; the shear strength of the pavement structure after adding modified UHPC joint filling material is increased by up to 89.2% compared with ordinary cement mortar.

[0041] As a preferred technical solution of the present invention, the cleaning process in step (2) includes polishing the surface of the repair machine and dust removal and dehumidification by blower.

[0042] As a preferred technical solution of the present invention, the water pressure of the high-pressure water jet rough interface treatment in step (3) is 120~130MPa, such as 120MPa, 122MPa, 124MPa, 126MPa, 128MPa, 130MPa, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0043] The water flow rate is 140~200L / s, such as 140L / s, 150L / s, 160L / s, 170L / s, 180L / s, 190L / s, 200L / s, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0044] Preferably, the sand filling depth of the roughened interface after the high-pressure water jet roughening treatment is 2.4~4.0mm, such as 2.4mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0045] As a preferred technical solution of the present invention, the modified UHPC joint filler material comprises the following raw materials in weight percentage: cement 24.27%~28.22%, silica fume 3.64%~4.52%, microspheres 3.03%~3.76%, quartz powder 6.07%~11.29%, quartz sand 36.41%~41.38%, water 7.28%~9.41%, modified polymer 0.49%~0.94%, and high-efficiency water-reducing agent 0.48%~0.61%.

[0046] Preferably, the specific operation of step (4) is as follows: the modified UHPC sealant is filled into the cylinder of the sealant device by adjusting the grouting pump, the sealant device is started and the discharge hole at the end of the connecting pipe is aligned with the joint position, the sealant device is moved to continuously and evenly inject the modified UHPC sealant into the joint position, the joint position along the longitudinal direction is injected first, and the joint position along the transverse direction is injected laterally. After the joint position is completely filled, the modified UHPC sealant is smoothed and collected with a scraper before it is surface dry. The setting time is not less than 24 hours to form a modified UHPC sealant bonding layer.

[0047] Preferably, the flame temperature of the flame treatment in step (5) is ≥1500℃, such as 1500℃, 1600℃, 1700℃, 1800℃, 1900℃, 2000℃, etc., but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0048] Preferably, the moving speed of the spray gun for the flame treatment is 20~30cm / s, such as 20cm / s, 22cm / s, 24cm / s, 26cm / s, 28cm / s, 30cm / s, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0049] The distance between the spray gun and the surface of the stone slab is 150~250mm, such as 150mm, 160mm, 170mm, 180mm, 190mm, 200mm, 210mm, 220mm, 230mm, 240mm, 250mm, etc., but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0050] Compared with the prior art, the present invention has at least the following beneficial effects:

[0051] (1) This invention improves the shear resistance of the pavement by setting a modified UHPC joint filler bonding layer in the composite stone pavement structure. The modified ultra-high performance cement-based composite material used in this bonding layer has excellent mechanical properties and impermeability. At the same time, the addition of modified polymers to the material further increases its interfacial bonding effect, thereby effectively suppressing the shear failure phenomenon at the stone slab joints under vehicle load cycles. The modified UHPC joint filler bonding layer has good rigidity and crack resistance. On the other hand, this rigid thin-layer material itself can exhibit excellent long-term service stability and high fatigue life, which greatly improves the structural performance of the stone pavement.

[0052] (2) This invention uses modified UHPC composite material for casting, combined with stone slabs with high-pressure water jet surface roughening treatment, to form a rigid stone slab surface layer. It makes full use of the performance and advantages of modified UHPC, improves the shear resistance and interfacial bonding performance of the stone slab pavement, reduces shear failure at the stone slab joints under load, reduces the phenomenon of debonding between adjacent stone slabs in the surface layer, and improves the structural and overall strength of the pavement. The use of on-site composite material casting and joint filling device ensures high joint filling quality and construction efficiency, which is conducive to the tight bonding between marble slabs and modified UHPC material, and effectively enhances the interfacial bonding force. The shear strength of the pavement structure after adding modified UHPC composite material is increased by up to 89.2% compared with ordinary cement mortar.

[0053] (3) The construction method of the present invention is simple and efficient, the required materials are widely available and easy to prepare, and it is highly compatible with mechanized construction mode. It can not only shorten the construction cycle and speed up the opening of traffic, but also effectively delay the functional degradation of the joint filling material, improve the shear resistance of the stone slab structure, greatly improve the structural durability, and extend the service life of the stone slab pavement. In addition, the present invention can also be used for urban square pavement projects. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of a stone pavement with high shear resistance provided by the present invention.

[0055] Figure 2 This is a flowchart illustrating the joint filling process of a construction method for a stone pavement with high shear resistance provided by the present invention.

[0056] Figure 3 This is a schematic diagram of the joint filling construction method for a stone slab pavement with high shear resistance provided by the present invention.

[0057] The components are as follows: 1. Subbase; 2. Cement concrete leveling layer; 3. Mortar bedding layer; 4. Stone slab surface layer; 5. Modified UHPC joint filling and bonding layer; 6. Joint location; 7. Joint filling device; 40. Grouting pump; 41. Material cylinder; 42. Connecting pipe; 43. Discharge hole; 44. Scraper. Detailed Implementation

[0058] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0059] Example 1

[0060] This embodiment provides a construction method for a stone slab pavement structure with high shear resistance, the construction method including the following steps:

[0061] (1) A cement concrete leveling layer 2 and a mortar cushion layer 3 are poured sequentially on the upper part of the base layer 1;

[0062] The base layer 1 is the original C25 plain concrete layer; the cement concrete leveling layer 2 is a C40 fine aggregate concrete leveling layer with a thickness of 60mm; the mortar cushion layer 3 is an M30 cement mortar cushion layer with a thickness of 40mm.

[0063] (2) The mortar bedding layer 3 is cleaned and the size of the stone slabs and the paving area are designed;

[0064] The cleaning process includes surface polishing with a finishing machine and dust and moisture removal with a blower; the stone slab is 200mm long, 200mm wide, and 200mm high, with a length-to-height ratio of 1.0.

[0065] (3) The side surface of the stone slab is roughened by high-pressure water jet and then the stone slab is laid.

[0066] The water pressure for the high-pressure water jet roughening interface treatment is 120 MPa, and the water flow rate is 150 L / s; the sand filling depth of the roughened interface after the high-pressure water jet roughening interface treatment is 2.4 mm.

[0067] (4) The modified UHPC joint filler material is injected into the joint of the adjacent stone slabs using a joint filling device, and after solidification, a modified UHPC joint filling adhesive layer 5 is formed.

[0068] The modified UHPC joint filler material comprises the following raw materials in weight percentages: cement 27.22%, silica fume 3.85%, microspheres 3.36%, quartz powder 10.12%, quartz sand 38.36%, water 8.45%, modified polymer 0.64%, and high-efficiency water-reducing agent 0.56%; the modified UHPC joint filler material has a 28-day compressive strength of 124.9 MPa and a shear strength bonded to the stone slab surface layer of 2.41 MPa;

[0069] The specific operation of step (4) is as follows: the modified UHPC sealant is filled into the cylinder 41 of the sealant device 7 by adjusting the grouting pump 40, the sealant device 7 is started and the discharge hole 43 at the end of the connecting pipe 42 is aligned with the joint position 6, the sealant device 7 is moved to continuously and evenly inject the modified UHPC sealant into the joint position 6, the joint position 6 along the longitudinal direction is injected first, and the joint position 6 along the transverse direction is injected laterally. After the joint position 6 is completely filled, the modified UHPC sealant is trimmed and smoothed with a scraper 44 and excess material is collected before it is surface dry. The setting time is not less than 24 hours to form a modified UHPC sealant bonding layer.

[0070] (5) The surface of the stone slab surface layer is flamed and cured before traffic is opened to complete the construction of the stone slab pavement structure;

[0071] The flame temperature for the flamed surface treatment is 2000℃; the moving speed of the flamed surface treatment spray gun is 28cm / s, and the distance between the spray gun and the surface of the stone slab is 250mm.

[0072] Example 2

[0073] This embodiment provides a construction method for a stone slab pavement structure with high shear resistance, the construction method including the following steps:

[0074] (1) A cement concrete leveling layer 2 and a mortar cushion layer 3 are poured sequentially on the upper part of the base layer 1;

[0075] The base layer 1 is the original C25 plain concrete layer; the cement concrete leveling layer 2 is a C40 fine aggregate concrete leveling layer with a thickness of 60mm; the mortar cushion layer 3 is an M30 cement mortar cushion layer with a thickness of 40mm.

[0076] (2) The mortar bedding layer 3 is cleaned and the size of the stone slabs and the paving area are designed;

[0077] The cleaning process includes surface polishing with a finishing machine and dust and moisture removal with a blower; the stone slab is 200mm long, 200mm wide, and 200mm high, with a length-to-height ratio of 1.

[0078] (3) The side surface of the stone slab is roughened by high-pressure water jet and then the stone slab is laid.

[0079] The water pressure for the high-pressure water jet roughening interface treatment is 125 MPa, and the water flow rate is 180 L / s; the sand filling depth of the roughened interface after the high-pressure water jet roughening interface treatment is 3.6 mm.

[0080] (4) The modified UHPC joint filler material is injected into the joint of the adjacent stone slabs using a joint filling device, and after solidification, a modified UHPC joint filling adhesive layer 5 is formed.

[0081] The modified UHPC joint filler material comprises the following raw materials in weight percentages: cement 27.22%, silica fume 3.85%, microspheres 3.36%, quartz powder 10.12%, quartz sand 38.36%, water 8.45%, modified polymer 0.64%, and high-efficiency water-reducing agent 0.56%; the modified UHPC joint filler material has a 28-day compressive strength of 124.9 MPa and a shear strength bonded to the stone slab surface layer of 2.78 MPa;

[0082] The specific operation of step (4) is as follows: the modified UHPC sealant is filled into the cylinder 41 of the sealant device 7 by adjusting the grouting pump 40, the sealant device 7 is started and the discharge hole 43 at the end of the connecting pipe 42 is aligned with the joint position 6, the sealant device 7 is moved to continuously and evenly inject the modified UHPC sealant into the joint position 6, the joint position 6 along the longitudinal direction is injected first, and the joint position 6 along the transverse direction is injected laterally. After the joint position 6 is completely filled, the modified UHPC sealant is trimmed and smoothed with a scraper 44 and excess material is collected before it is surface dry. The setting time is not less than 24 hours to form a modified UHPC sealant bonding layer.

[0083] (5) The surface of the stone slab surface layer is flamed and cured before traffic is opened to complete the construction of the stone slab pavement structure;

[0084] The flame temperature for the flamed surface treatment is 2000℃; the moving speed of the flamed surface treatment spray gun is 28cm / s, and the distance between the spray gun and the surface of the stone slab is 250mm.

[0085] Example 3

[0086] This embodiment provides a construction method for a stone slab pavement structure with high shear resistance, the construction method including the following steps:

[0087] (1) A cement concrete leveling layer 2 and a mortar cushion layer 3 are poured sequentially on the upper part of the base layer 1;

[0088] The base layer 1 is the original C25 plain concrete layer; the cement concrete leveling layer 2 is a C40 fine aggregate concrete leveling layer with a thickness of 60mm; the mortar cushion layer 3 is an M30 cement mortar cushion layer with a thickness of 40mm.

[0089] (2) The mortar bedding layer 3 is cleaned and the size of the stone slabs and the paving area are designed;

[0090] The cleaning process includes surface polishing with a finishing machine and dust and moisture removal with a blower; the stone slab is 200mm long, 200mm wide, and 200mm high, with a length-to-height ratio of 1.

[0091] (3) The side surface of the stone slab is roughened by high-pressure water jet and then the stone slab is laid.

[0092] The water pressure for the high-pressure water jet roughening interface treatment is 120 MPa, and the water flow rate is 150 L / s; the sand filling depth of the roughened interface after the high-pressure water jet roughening interface treatment is 2.4 mm.

[0093] (4) The modified UHPC joint filler material is injected into the joint of the adjacent stone slabs using a joint filling device, and after solidification, a modified UHPC joint filling adhesive layer 5 is formed.

[0094] The modified UHPC joint filler material comprises the following raw materials by weight percentage: cement 27.22%, silica fume 3.85%, microspheres 3.36%, quartz powder 10.12%, quartz sand 38.36%, water 8.45%, modified polymer 0.80%, and high-efficiency water-reducing agent 0.60%; the modified UHPC joint filler material has a 28-day compressive strength of 116.3 MPa and a shear strength bonded to the stone slab surface layer of 2.66 MPa;

[0095] The specific operation of step (4) is as follows: the modified UHPC sealant is filled into the cylinder 41 of the sealant device 7 by adjusting the grouting pump 40, the sealant device 7 is started and the discharge hole 43 at the end of the connecting pipe 42 is aligned with the joint position 6, the sealant device 7 is moved to continuously and evenly inject the modified UHPC sealant into the joint position 6, the joint position 6 along the longitudinal direction is injected first, and the joint position 6 along the transverse direction is injected laterally. After the joint position 6 is completely filled, the modified UHPC sealant is trimmed and smoothed with a scraper 44 and excess material is collected before it is surface dry. The setting time is not less than 24 hours to form a modified UHPC sealant bonding layer.

[0096] (5) The surface of the stone slab surface layer is flamed and cured before traffic is opened to complete the construction of the stone slab pavement structure;

[0097] The flame temperature for the flamed surface treatment is 2000℃; the moving speed of the flamed surface treatment spray gun is 28cm / s, and the distance between the spray gun and the surface of the stone slab is 250mm.

[0098] Comparative Example 1

[0099] This comparative example provides a construction method for a stone pavement structure with high shear resistance. The difference from Example 1 is that the high-pressure water jet roughening interface treatment described in step (3) is not performed. All other methods and steps are the same as in Example 1.

[0100] Comparative Example 2

[0101] This comparative example provides a construction method for a stone pavement structure with high shear resistance. The difference from Example 1 is that the modified UHPC joint filler in step (4) is replaced with ordinary cement mortar, and the rest of the method steps are the same as in Example 1.

[0102] Performance testing

[0103] The bond shear strength of the stone pavement laid in Examples 1-3 and Comparative Examples 1-2 was tested using a WanCe hydraulic testing machine. A special fixing clamp was used to fix the stone pavement, and the bond shear strength value of the rough surface of the stone pavement was detected. The test results are shown in Table 1.

[0104] In addition, in-situ shear tests were conducted on the stone slabs to simulate the stress on the stone slabs under static load and braking action of heavy vehicles. The effects of sand filling depth at different rough interfaces and different modified polymer dosages on the mechanical response of the paving system were compared. By controlling the heavy load + braking conditions, the deformation and structural integrity of the paving were measured.

[0105] Table 1

[0106]

[0107] The test results show that:

[0108] (1) As can be seen from Examples 1 to 3, compared with the stone pavement structure with a rough interface sand filling depth of 2.4 mm in Example 1, the pavement structure with a rough interface sand filling depth of 3.6 mm in Example 2 has a 15.4% higher shear strength, better deformation resistance, and the stone pavement surface layer has good overall stability and durability. In addition, compared with the pavement structure in Example 1, the modified polymer content of the joint filler in Example 3 increased by 25%, and the shear strength was also improved to a certain extent, the vertical deformation was reduced, and the pavement structure had no cracks. The test results all show that the modified UHPC material of the present invention can effectively enhance the shear resistance and durability of the material at the joint of the stone pavement and reduce the shear failure of the interface. Moreover, appropriately increasing the rough interface sand filling depth and the modified polymer content in the modified UHPC composite material can further enhance the shear resistance and deformation resistance of the stone pavement.

[0109] (2) By comparing Example 1 with Comparative Example 1, it can be seen that Comparative Example 1 does not perform high-pressure water jet rough interface treatment, resulting in poor deformation resistance and shear strength of the pavement structure, increased vertical deformation, and a small number of fine cracks on the bonding side of the pavement structure.

[0110] (3) As can be seen from Example 1 and Comparative Example 2, compared with the use of ordinary cement mortar as the joint filling material in Comparative Example 1, the shear strength of the stone pavement using modified UHPC composite material as the joint filling material in Example 1 is increased by 58.6%, the vertical deformation and horizontal displacement are significantly reduced, the structural form is more complete, and no cracks appear.

[0111] In summary, this invention provides a stone pavement with high shear resistance and its construction method. By casting modified UHPC composite materials and combining them with stone slabs that have undergone surface roughening treatment using high-pressure water jetting, a rigid stone slab surface layer is formed. This fully utilizes the performance and advantages of modified UHPC, improving the shear resistance and interfacial bonding properties of the stone pavement, reducing shear failure at the stone slab joints under load, minimizing debonding between adjacent stone slabs in the surface layer, and enhancing the structural and overall strength of the pavement. The construction method of this invention is simple and efficient, requiring widely available and easily prepared materials. It is also highly adaptable to mechanized construction methods, not only shortening the construction cycle and accelerating traffic opening, but also effectively delaying the functional degradation of joint filler materials, improving the shear resistance of the stone slab structure, significantly increasing structural durability, and extending the service life of the stone pavement. Furthermore, this invention can also be used in urban plaza pavement projects.

[0112] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A stone slab pavement structure with high shear resistance, characterized in that, The stone pavement structure includes, from top to bottom, a stone slab surface layer, a mortar cushion layer, a cement concrete leveling layer, and a base layer; The stone slab surface layer consists of at least two stone slabs; the adjacent stone slabs are bonded together by an adhesive layer; the adhesive layer is a modified UHPC joint filler adhesive layer; the joints on both sides of the stone slabs are treated with high-pressure water jet roughening interface treatment.

2. The stone slab pavement structure according to claim 1, characterized in that, The stone slabs for the surface layer are natural marble blocks; the length of the stone slabs is 200~250mm, the width is 200~250mm, and the thickness is 180~200mm; the length-to-height ratio of the stone slabs is ≥1.

0.

3. The stone pavement structure according to claim 1 or 2, characterized in that, The adhesive layer uses a modified UHPC sealant; the modified polymer doping content of the modified UHPC sealant is ≥0.49%; Preferably, the 28-day compressive strength of the adhesive layer is 110~140MPa, the shear strength of the bond with the stone slab surface layer is 2.4~3.0MPa, and the maximum vertical deformation under in-situ shear is ≤0.02mm.

4. The stone pavement structure according to any one of claims 1-3, characterized in that, The mortar cushion layer has a 28-day compressive strength of 35~42MPa and a flexural strength of 4.0~4.8MPa; Preferably, the thickness of the mortar pad is 20~50mm.

5. The stone pavement structure according to any one of claims 1-4, characterized in that, The cement concrete leveling layer is a C40 fine aggregate concrete layer; Preferably, the 28-day compressive strength of the cement concrete leveling layer is 48~55MPa, and the flexural strength is 3.8~4.5MPa; Preferably, the thickness of the cement concrete leveling layer is 40~90mm.

6. The stone pavement structure according to any one of claims 1-5, characterized in that, The base layer is a C25 plain concrete layer; Preferably, the 28-day compressive strength of the subbase is 30~36MPa, and the flexural strength is 2.6~2.9MPa; Preferably, the thickness of the base layer is 80~180mm.

7. A construction method for a stone pavement structure as described in any one of claims 1-6, characterized in that, The construction method includes the following steps: (1) A cement concrete leveling layer and a mortar cushion layer are poured sequentially on the upper part of the base layer; (2) Remove the mortar bedding layer and design the size of the stone slabs and the paving area; (3) The side surface of the stone slab is roughened by high-pressure water jet and then the stone slab is laid. (4) The modified UHPC joint filler material is injected into the joint of the adjacent stone slabs using a joint filling device, and after solidification, a modified UHPC joint filling adhesive layer is formed. (5) The surface of the stone slab is flamed and cured before traffic is opened to complete the construction of the stone slab pavement structure.

8. The construction method according to claim 7, characterized in that, The cleaning process described in step (2) includes polishing the surface of the repair machine and dust removal and dehumidification by blower.

9. The construction method according to claim 7 or 8, characterized in that, The water pressure for the high-pressure water jet roughening interface treatment in step (3) is 120~130MPa and the water flow rate is 140~200L / s; Preferably, the sand filling depth of the roughened interface after the high-pressure water jet roughening treatment is 2.4~4.0mm.

10. The construction method according to any one of claims 7-9, characterized in that, The modified UHPC joint filler material comprises the following raw materials in weight percentages: cement 24.27%~28.22%, silica fume 3.64%~4.52%, microspheres 3.03%~3.76%, quartz powder 6.07%~11.29%, quartz sand 36.41%~41.38%, water 7.28%~9.41%, modified polymer 0.49%~0.94%, and high-efficiency water-reducing agent 0.48%~0.61%; Preferably, the specific operation of step (4) is as follows: the modified UHPC sealant is filled into the cylinder of the sealant device by adjusting the grouting pump, the sealant device is started and the discharge hole at the end of the connecting pipe is aligned with the joint position, the sealant device is moved to continuously and evenly inject the modified UHPC sealant into the joint position, the joint position along the longitudinal direction is injected first, and the joint position along the transverse direction is injected laterally. After the joint position is completely filled, the modified UHPC sealant is smoothed and collected with a scraper before it is surface dry. The setting time is not less than 24 hours to form a modified UHPC sealant bonding layer. Preferably, the flame temperature of the flame treatment in step (5) is ≥1500℃; the moving speed of the spray gun for the flame treatment is 20~30cm / s, and the distance between the spray gun and the surface of the stone slab is 150~250mm.

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