A dry structural material in-situ forming method based on gas phase activation

Abstract

The application provides a dry structure material in-situ forming method based on gas phase activation, comprising: filling dry structure material in dry state in a complex structure site; sealing the filling site and connecting to a controllable steam source; introducing controllable low-temperature saturated water vapor into the sealed site, taking the water vapor as the only initial hydration source to activate the dry structure material as a whole until it is solidified into a whole with structural strength.

Description

Technical Field

[0001] This application relates to the fields of building construction and advanced building materials technology, specifically to an in-situ forming method for dry structural materials based on gas phase activation. Background Technology

[0002] In building, bridge, and special structure engineering, there are often many complex parts that are difficult to effectively cast using traditional methods, for example: Post-pouring strip: A long period of time (usually more than 60 days) needs to be reserved to allow the main structure to settle and stabilize. During this period, this part is exposed, which seriously affects the subsequent waterproofing, insulation and decorative layer construction, causing delays and overlapping of procedures.

[0003] Complex irregular nodes: such as areas with dense reinforcement, prestressed anchorage zones, and complex nodes in steel-concrete composite structures, where space is narrow and vibratory rods cannot be inserted, traditional grouting materials are prone to producing voids due to bleeding and shrinkage, making it difficult to guarantee quality.

[0004] Repair and reinforcement of existing structural cavities: irregular shape, damp surface or standing water, difficult to erect formwork, and ordinary concrete or mortar cannot effectively fill and bond them.

[0005] Internal cavities in architectural decorative structures: Thickened or reinforced areas inside decorative components such as GRC and GRG cannot be sealed by the mold, requiring a self-filling and self-sealing material.

[0006] Existing technologies primarily rely on high-fluidity grouting materials or self-compacting concrete. However, these materials still require on-site mixing with water, leading to performance fluctuations due to inaccurate water-cement ratio control, short fluidity retention time, and easy formation of interfacial gaps due to shrinkage after hardening. More importantly, they cannot address the core requirement of "dry storage and selective activation," i.e., triggering final curing at any desired time after pre-filling, thereby merging the structural waiting period and material curing period into one, completely eliminating the need for additional processing steps.

[0007] Furthermore, conventional "steam curing" is a post-treatment process applied to concrete products that already contain liquid water and are in the initial stage of formation, aiming to accelerate their strength development. In contrast, the "gas-phase activation" proposed in this invention is a primary hydration initiation mechanism. It acts on completely dry mixtures that have not undergone any hydration reaction, using gaseous water molecules as the sole initial hydration source to achieve a qualitative change from "dry powder" to "integral structure." This is fundamentally different in principle and application. Summary of the Invention

[0008] In view of this, this application aims to overcome the shortcomings of the prior art by using specially made dry structural materials for in-situ filling of complex structural parts, and by using a construction method, special material system and supporting system to solidify the whole structure through a controllable gas phase (water vapor) activation method.

[0009] Specifically, a dedicated dry structural material system is provided, characterized by mainly comprising: cementing materials, vapor-phase hydration promoting and transporting media, skeleton and fillers, and functional additives, wherein the cementing materials account for 25%-40% by weight; the vapor-phase hydration promoting and transporting media accounts for 3%-10% by weight; the skeleton and fillers account for 45%-65% by weight; and the functional additives account for 2%-8% by weight. Furthermore, the cementing material includes sulfoaluminate cement, as well as ultrafine silicate cement or ultrafine slag powder.

[0010] Furthermore, the vapor-phase hydration promoting and transporting medium includes modified porous zeolite powder or diatomaceous earth, as well as nano-silica.

[0011] Furthermore, the skeleton and filler include graded quartz sand and fine active fillers.

[0012] Furthermore, the functional additives include polycarboxylate superplasticizers, superabsorbent polymers (SAP) internal curing and water-retaining agents, ettringite micro-expansion agents, and polypropylene fiber toughening fibers.

[0013] On the other hand, this application provides an in-situ molding method for dry structural materials based on gas phase activation. The method employs any of the aforementioned dedicated dry structural material systems, filling the complex structural parts with the dry structural material in a dry state; sealing the filling parts and connecting them to a controllable steam source; introducing controllable low-temperature saturated water vapor into the sealed parts, using water vapor as the sole initial hydration source, to activate the dry structural material as a whole until it solidifies into a whole with structural strength.

[0014] Furthermore, a method for in-situ forming of dry structural materials based on gas-phase activation includes the following specific steps: Step 1: Construction preparation and base surface treatment; Reinforcing steel binding and debris removal are carried out on the area to be filled, ensuring that there is no standing water or oil. Step 2: Dry material filling; The above-mentioned dry structural material is filled into the target cavity using a special dry spraying machine or manually, and moderately compacted to ensure that it is filled and forms a preliminary dense accumulation. No water is added in this step. Step 3: Seal and connect to the system; use a flexible composite sealing cover that fits the shape of the part to cover it tightly, generally covering the outside of the mold shell to prevent water vapor from leaking out from a certain joint, so as to achieve a complete seal, and connect the pre-embedded sensor and steam pipeline network to the main unit of the gas phase activation system.

[0015] Step 4: Gas-phase activation. This is the most crucial step and consists of three stages: Low-temperature infiltration period: The system is introduced with saturated steam at low temperature (40-50℃) and low pressure for about 1-2 hours. The steam gradually infiltrates and evenly fills the pores of the material, allowing the gas phase hydration promoter to fully absorb moisture and initially activate the surface of the cementitious material. Constant pressure and temperature activation period: Gradually increase the steam temperature and pressure to the set value, such as 70-90℃, with a slight positive pressure, and maintain it for 6-24 hours; Gradient cooling curing period: Stop heating and control the slow release of steam to allow the components to cool slowly to near ambient temperature in a sealed environment; Step 5: Effect judgment and acceptance; The system automatically judges whether the activation is completed based on the preset temperature and humidity change curve and duration. After completion, the sealing cover and pipeline are removed, and the strength and density of the molded body are tested.

[0016] This application also provides a system for implementing the above-described dry structural material in-situ forming method, specifically including: a steam generation and regulation unit, a sealing unit adapted to the shape of complex parts, a sensing unit arranged inside the filling material, and an intelligent control unit that dynamically controls the steam generation and regulation unit based on feedback signals from the sensing unit.

[0017] Compared with existing technologies, this application provides a method for in-situ molding of dry structural materials based on gas-phase activation, achieving "dry prefabrication and filling, precise activation at opportune time, and uniform curing" of complex structural parts. It provides a special dry structural material that can be stored and transported in a dry state for extended periods and can be efficiently and uniformly activated under specific gas-phase environments; an activation method with controllable water vapor transport and infiltration ensures thorough hydration reactions within the material; and it provides supporting construction processes and systems, enabling the technology to be applied in a standardized and reproducible manner to various engineering scenarios. This method liberates construction procedures, allowing surface sealing to be completed during the structural settlement waiting period, significantly shortening the overall construction period, and improving the structural molding quality and reliability of complex parts. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] The structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the implementation conditions of this application. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0020] Figure 1 A schematic diagram of the process for an in-situ dry structural material forming method based on vapor phase activation, as designed in this application. Detailed Implementation The embodiments of this application are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] This application provides a dry structural material in-situ molding method based on gas phase activation, which realizes "dry pre-filling, timed precise activation, and overall uniform curing" of complex structural parts.

[0022] First, for complex parts that require pouring, it is necessary to design a suitable special dry structural material system, which mainly includes the following material system: cementitious materials, gas phase hydration promoting and transporting medium, skeleton and filler, functional additives and other components.

[0023] (1) Cementitious materials, 25%-40% by weight, key materials mainly include: Sulfoaluminate cement (SAC) provides early strength and micro-expansion; Ultrafine silicate cement (OPC) or ultrafine slag powder (GGBS) provides later-stage strength and durability.

[0024] The core function is to optimize reaction kinetics through the combination of these two components, reducing the driving force required for the reaction. This provides the final strength and exhibits high gas-phase hydration activity.

[0025] (2) Gas-phase hydration promoting and transporting medium, 3%-10% by weight, key materials mainly include: Modified porous zeolite powder or diatomaceous earth, after hydrophilic modification, possesses a huge specific surface area and hygroscopicity, acting as a "molecular sponge" and transport channel. Nano-silica, with its ultra-high activity, greatly increases the nucleation sites for hydration reactions. Its core function is to capture and conduct water vapor, and promote the initiation and propagation of hydration reactions in low-humidity environments.

[0026] (3) Skeleton and filler, weight percentage 45%-65%, key materials mainly include: Graded quartz sand, the main skeleton material. Fine active fillers, such as fly ash and metakaolin.

[0027] For surface treatment, the aggregate needs to be treated with a micro-hydrophobic coating (such as a silane coupling agent) to prevent moisture absorption during storage, but without hindering vapor passage. Its core function is to construct the material skeleton and adjust bulk density and properties.

[0028] (4) Functional additives, 2%-8% by weight, key materials mainly include: Water-reducing agent (polycarboxylate-based) ensures that the material can still form a dense packing under limited gas phase water conditions; Internal water-retaining agent (high molecular weight water-absorbing resin micro powder) locks in water during the activation period to ensure deep hydration; micro-expansion agent (calcite-based) compensates for possible shrinkage and ensures tight interface; toughening fiber (polypropylene fiber) improves crack resistance.

[0029] Its core functions are: regulating workability, activation process and final performance.

[0030] The aforementioned dry structural materials can be stored stably for a long time in a dry environment and can be activated to form a high-strength structure in a low-temperature saturated water vapor environment.

[0031] A well-configured dry structural material system requires a set of construction methods adapted to it.

[0032] This application proposes a method for in-situ forming of dry structural materials based on gas-phase activation, including the following: Figure 1 The five main steps shown are centered around the use of an intelligent control system to dynamically adjust steam parameters based on real-time feedback, achieving uniform activation of the material from the inside out. Details are as follows: Step 1: Construction Preparation and Base Surface Treatment; Reinforcing steel is tied and debris is removed from the areas to be filled, ensuring no standing water or oil stains. According to the design, a semi-rigid outer mold adapted to the structural shape is used, and a steam capillary network is pre-laid. Since dry-mixed or semi-bulk materials do not generate excessive lateral pressure, installation and reinforcement are very simple; generally, only the structural shape needs to be provided, and localized reinforcement can be achieved using irregularly shaped hoop clamps. For more complex structures, staged molding can also be used. It is worth emphasizing that this method is not suitable for load-bearing structures.

[0033] Step 2: Dry material filling; The above-mentioned dry structural material is filled into the target cavity using a special dry shotcrete machine or manually, and moderately compacted (e.g., by using a pneumatic tamping rod) to ensure that it is filled and forms a preliminary dense accumulation, but water is strictly prohibited.

[0034] Step 3: Sealing and System Connection; Use a flexible composite sealing cover (such as rubber-coated fabric) adapted to the shape of the part for a tight cover, generally covering the outside of the mold shell, to prevent moisture from leaking out completely from a certain joint, achieving a complete seal. Connect the pre-embedded sensors and steam pipeline network to the main unit of the gas phase activation system.

[0035] Step 4: Gas-phase activation. This is the most crucial step and consists of three stages: Low-temperature infiltration period: The system is purged with low-temperature (40-50℃) and low-pressure saturated steam for approximately 1-2 hours. The purpose is to allow the steam to gradually infiltrate and evenly fill the pores of the material, enabling the vapor-phase hydration accelerator to fully absorb moisture and initially activate the surface of the cementitious material.

[0036] Constant pressure and temperature activation period: Gradually increase the steam temperature and pressure to the set value (e.g., 70-90℃, slightly positive pressure) and maintain it for 6-24 hours (adjusted according to component size and strength requirements). This stage is the main period of hydration reaction. The control system dynamically adjusts the steam supply based on sensor feedback (internal temperature and humidity rise curves) to ensure a balanced reaction.

[0037] Gradient cooling curing period: Stop heating and control the slow release of steam to allow the components to cool slowly to near ambient temperature in a sealed environment. This process helps reduce thermal stress and improve final strength.

[0038] Step 5: Effect judgment and acceptance; The system automatically judges whether the activation is completed based on the preset temperature and humidity change curve and duration. After completion, the sealing cover and pipeline are removed, and the strength (such as the rebound method) and density (tapping method) of the molded body are tested.

[0039] This application also provides a system for implementing the above-described dry structural material in-situ forming method, specifically including: a steam generation and regulation unit, a sealing unit adapted to the shape of complex parts, a sensing unit arranged inside the filling material, and an intelligent control unit that dynamically controls the steam generation and regulation unit based on feedback signals from the sensing unit.

[0040] Example 1: Construction of Ancient Building Design The process of "skeleton shaping, dry material filling, and in-situ gas phase activation" is adopted to achieve "aerial shaping and in-situ growth".

[0041] Step 1: Shape Positioning and Skeleton Construction A 3D laser scan is performed on the damaged decorative elements to obtain a precise digital model. In the original location of the area to be repaired, a flexible steel mesh is manually shaped and bound according to the digital model to construct an internal spatial framework that matches the target design. This framework also serves as the load-bearing support for the infill material.

[0042] Step Two: Flexible External Mold Installation and System Pre-embedding: A layer of high-strength, heat-resistant flexible composite film (such as silicone-coated fiberglass cloth) is laid on the outside of the shaped steel frame as the negative mold for the design and the base for the final exterior finish. It is then secured to the frame using binding or lightweight clamps to form a sealed cavity. Within this sealed cavity, depending on the complexity of the design, "tree-like" or "mesh-like" microporous steam capillary hoses and miniature temperature and humidity sensors are pre-installed. The pipes and sensor cables are led out from concealed locations.

[0043] Step 3: Dry Material Filling: Using a dedicated low-pressure dry spraying equipment, the dry structural material of this invention is evenly sprayed into the cavity formed by the steel frame and flexible outer mold through the pre-reserved filling port. During the filling process, the outer mold can be gently tapped to ensure the material is compacted and free of voids. After filling, the filling port is sealed.

[0044] Step Four: In-situ Controlled Gas Phase Activation: Connect the pre-embedded steam pipes and sensors to the mobile gas phase activation unit (which can be placed on the ground near the ancient building). Start the activation program. To protect the ancient building itself, a "low-temperature, long-duration" activation strategy is adopted: low-temperature saturated steam at 50-60℃ is introduced and maintained for 48-72 hours. The system intelligently adjusts the steam introduction rhythm based on internal sensor data to ensure that every minute part of the design (such as the fur and claws of the animal's mouth) is uniformly cured. After activation, the material is cured into a high-strength whole within the cavity and tightly bonded to the internal steel frame and the external flexible membrane.

[0045] Step 5: Outer film treatment and aging: After activation and cooling, the flexible outer film can be retained as a protective layer, or surface treatment can be carried out according to aesthetic requirements (such as spraying antique-style paint or aging).

[0046] Ultimately, the restored components blended perfectly with the ancient building in terms of texture and color, and because they were grown in situ, they were seamlessly integrated with the base, avoiding a "patchwork" feel.

[0047] This application provides a novel method for in-situ molding of dry structural materials based on vapor-phase activation, offering the industry a new approach to achieve "dry pre-filling, precise timing activation, and uniform overall curing" of complex structural components. This method can positively contribute to solving common problems in the industry and possesses the following characteristics: The process is revolutionary, achieving "dry filling and timely activation," merging the structural waiting period and curing period, greatly releasing construction freedom, and shortening the critical path construction period by more than 30%.

[0048] With its superior quality and gas-phase activation penetration without dead angles, it solves the stubborn problems of uneven compaction and strength caused by difficulties in pouring and vibration in complex parts. The molded body is uniform and dense, and has reliable adhesion to the substrate.

[0049] The innovative materials system developed combines ultra-long dry-state stability with high-efficiency gas-phase reactivity, representing a breakthrough in materials design.

[0050] Intelligent control integrates sensing, feedback, and control, enabling construction quality to shift from "experience-based" to "data-driven," with predictable and traceable results.

[0051] It has a wide range of applications and is suitable for many scenarios where traditional processes are difficult to implement, such as post-pouring strips, complex nodes, reinforcement and repair, and connection of precast components. It is highly versatile.

[0052] Finally, it should be noted that the above embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the scope of the technology disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A dedicated dry structural material system, characterized in that, Mainly includes: The composition includes cementitious materials, gas phase hydration promoting and transporting media, skeleton and fillers, and functional additives, of which cementitious materials account for 25%-40%, gas phase hydration promoting and transporting media accounts for 3%-10%, skeleton and fillers account for 45%-65%, and functional additives account for 2%-8%.

2. The dedicated dry structural material system as described in claim 1, characterized in that: The cementing materials include sulfoaluminate cement, as well as ultrafine silicate cement or ultrafine slag powder.

3. The dedicated dry structural material system as described in claim 1, characterized in that: The vapor phase hydration promoting and transporting medium includes modified porous zeolite powder or diatomaceous earth, as well as nano-silica.

4. The dedicated dry structural material system as described in claim 1, characterized in that: The skeleton and filler include graded quartz sand and fine active fillers.

5. The dedicated dry structural material system as described in claim 1, characterized in that: Functional additives include polycarboxylate superplasticizers, superabsorbent polymers (SAMR) internal curing and water-retaining agents, calcite micro-expansion agents, and polypropylene fiber toughening fibers.

6. A method for in-situ molding of dry structural materials based on gas phase activation, comprising using any one of the dedicated dry structural material systems of claims 1-5, filling the dry structural material in a dry state into a complex structural part; sealing the filling part and connecting it to a controllable steam source; introducing controllable low-temperature saturated water vapor into the sealed part, using water vapor as the sole initial hydration source, to activate the dry structural material as a whole until it solidifies into a whole with structural strength.

7. The in-situ forming method for dry structural materials based on gas-phase activation as described in claim 6, characterized in that, The method includes the following specific steps: Step 1: Construction preparation and base surface treatment; Reinforcing steel binding and debris removal are carried out on the area to be filled, ensuring that there is no standing water or oil. Step 2: Dry material filling; The above-mentioned dry structural material is filled into the target cavity using a special dry spraying machine or manually, and moderately compacted to ensure that it is filled and forms a preliminary dense accumulation. No water is added in this step. Step 3: Seal and connect to the system; use a flexible composite sealing cover that fits the shape of the part to cover it tightly, generally covering the outside of the mold shell to prevent water vapor from leaking out from a certain joint, so as to achieve a complete seal, and connect the pre-embedded sensor and steam pipeline network to the main unit of the gas phase activation system. Step 4: Gas-phase activation. This is the most crucial step and consists of three stages: Low-temperature infiltration period: The system is introduced with saturated steam at low temperature (40-50℃) and low pressure for about 1-2 hours. The steam gradually infiltrates and evenly fills the pores of the material, allowing the gas phase hydration promoter to fully absorb moisture and initially activate the surface of the cementitious material. Constant pressure and temperature activation period: Gradually increase the steam temperature and pressure to the set value, such as 70-90℃, with a slight positive pressure, and maintain it for 6-24 hours; Gradient cooling curing period: Stop heating and control the slow release of steam to allow the components to cool slowly to near ambient temperature in a sealed environment; Step 5: Effect judgment and acceptance; The system automatically judges whether the activation is completed based on the preset temperature and humidity change curve and duration. After completion, the sealing cover and pipeline are removed, and the strength and density of the molded body are tested.

8. A system for implementing the dry structural material in-situ forming method according to claims 6-7, characterized in that, include: The steam generation and regulation unit, the sealing unit adapted to the shape of the complex part, the sensing unit arranged inside the filling material, and the intelligent control unit that dynamically controls the steam generation and regulation unit based on the feedback signal from the sensing unit.

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