A blockchain-based building material information processing method and system

Abstract

The application belongs to the technical field of building material information management, and particularly relates to a building material information processing method and system based on a block chain. The method comprises the following steps: allocating a physical anti-fake code and a block chain digital identifier to building materials, binding the two to form a material twin identifier through hashing, and combining BIM component unit information to build a BIM space-time binding anchor; collecting business and track data at the material transfer link, generating a voucher for chain storage after space-time deviation verification, dynamic consensus weight distribution and multi-party signature verification; building a binding state atlas based on a directed acyclic graph, performing differentiated atlas updating and cascading hash storage for material form change and multi-source aggregation scenarios; and when a traceability request is received, performing reverse traversal along the atlas, completing data verification and full-link information extraction. The application realizes the unique binding of material physical entities and digital identities, effectively improving the standardization of building engineering material management and the efficiency of quality supervision.

Description

Technical Field

[0001] This invention belongs to the field of building material information management technology, specifically relating to a blockchain-based method and system for processing building material information. Background Technology

[0002] Building materials refer to all kinds of materials used in construction projects. Efficient processing and reliable management of building material information are key to improving the efficiency of construction project management and ensuring project quality.

[0003] Traditional building material management solutions are mostly based on centralized relational databases or standalone BIM systems. In practical applications, the construction supply chain involves multiple heterogeneous entities such as construction companies, contractors, suppliers, and third-party monitoring agencies. Data between these parties is not shared, forming "information silos." At the same time, centralized storage mechanisms lack effective anti-tampering verification, and the authenticity of the original data before being uploaded to the blockchain is difficult to verify through multi-party collaboration. When quality problems occur in construction projects, it is also impossible to quickly locate the corresponding material batch and the entire chain of evidence information, resulting in a complex, time-consuming, and costly process for tracing responsibility, which fails to meet the needs of efficient and reliable material management and quality supervision in construction projects. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a blockchain-based method and system for processing building material information, in order to solve the problems in the background art mentioned above. The specific solution is as follows: This invention discloses a blockchain-based method for processing building material information, comprising the following steps: Physical anti-counterfeiting codes and blockchain digital identifiers are assigned to building materials, and after hash binding, material twin identifiers are formed; the three-dimensional spatial coordinate set and planned construction time window of the BIM component unit bound to the material twin identifier are extracted to form BIM spatiotemporal binding anchor points; In the business flow of building materials, the corresponding business data and real-time trajectory data are collected and processed, and the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point is compared. When the deviation is within the preset threshold, consensus weights are dynamically allocated according to node attributes and multi-party signature verification is performed. After the verification is passed, the status flow certificate of this link is generated and stored on the blockchain. Using the unit project of the building project as the root node, the BIM component unit as the end node, and the building material as the leaf node, a binding state map of the entire link of BIM component-material is constructed based on the directed acyclic graph. When building materials undergo shape changes or processing and assembly, the directed edges of the binding state graph are updated synchronously; when multiple source materials are aggregated into a single target component, a node aggregation operation is performed in the binding state graph, pointing the directed edges of the corresponding leaf nodes to the same target end node, and the state flow vouchers of each source material are subjected to cascade hash calculation to generate an aggregated evidence hash and anchor it to the target end node. When a traceability request for a target building component is received, the corresponding node in the binding status graph is located by the BIM component unit ID. The system then performs a depth-first traversal along the reverse edge of the directed acyclic graph, verifies the aggregated evidence hash and digital signature integrity of the nodes along the way, and extracts the full-link evidence data.

[0005] Optionally, the physical anti-counterfeiting code is a unique identifier corresponding to each building material, including any one of QR codes, RFID tags, or NFC tags; the hash binding is to perform irreversible hash calculations on the unique serial number of the physical anti-counterfeiting code and the blockchain digital identifier to generate a globally unique material twin identifier; the material twin identifier is bound one-to-one with all data throughout the entire life cycle of the building material; the three-dimensional spatial coordinate set is the complete boundary coordinate set of BIM component units under the unified engineering coordinate system of the project; the planned construction time window includes the planned arrival time of the building material and the planned construction time; the BIM spatiotemporal binding anchor point is the only pre-verification benchmark for verifying the compliance of the building material circulation.

[0006] Optionally, the processing of real-time trajectory data specifically includes: The real-time trajectory data is converted into a unified engineering coordinate system consistent with the BIM spatiotemporal binding anchor points using the project benchmark point seven-parameter conversion algorithm. Cluster the converted trajectory points within the planned construction time window to obtain the trajectory point set within that time window; The trajectory point set is compared with the complete boundary coordinate set of the BIM component unit to calculate the proportion of trajectory points falling within the component's spatial range, or the minimum spatial distance from the trajectory point to the component boundary, which serves as the quantitative basis for subsequent deviation comparison.

[0007] Optionally, when the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point exceeds a preset threshold, a compliance warning is triggered. The compliance warning includes: locking the subsequent business flow permissions of the corresponding building material, rejecting the current request for data on-chain storage, synchronizing the deviation anomaly data and the corresponding material twin identifier to the blockchain supervision node, and pushing the warning information to the responsible entity of the corresponding business link.

[0008] Optionally, consensus weights can be dynamically allocated based on node attributes. Specifically, consensus weights can be dynamically allocated to nodes such as construction units, supervision units, construction units, material suppliers, and third-party testing agencies based on the responsibility priority and correlation of business flow links.

[0009] Optionally, the binding status diagram of the entire BIM component-material link is set with the unit project as the root node, and then set down to sub-project nodes, sub-item project nodes, BIM component unit end nodes, and building material leaf nodes in sequence. The nodes at each level are associated with each other through unidirectional irreversible directed edges. The attributes of the directed edges include the node binding time, the hash value of the corresponding material twin identifier, and the digital signature of the associated node.

[0010] Optionally, the update of the directed edge of the bound state graph must be verified by the multi-party signature of the corresponding business process before it can be executed; the cascaded hash calculation is specifically as follows: according to the business flow sequence of each source material, the hash values ​​of the state flow vouchers of all source materials are concatenated and iterative irreversible hash calculation is performed to generate a globally unique aggregated evidence hash.

[0011] Optionally, the traceability request includes traceability of quality issues, traceability of compliance audits, and traceability of materials throughout the entire supply chain; after extracting the evidence data of the entire supply chain, it also includes: locating the business process, responsible entity and supporting documents corresponding to the problem based on the evidence data of the entire supply chain, and generating an unalterable traceability report of the entire life cycle of materials.

[0012] Optionally, deviation comparison, consensus weight allocation, multi-party signature verification, binding state graph update, cascade hash calculation, and tracing traversal operation are all automatically executed through smart contracts pre-deployed on the blockchain; the blockchain is an engineering consortium blockchain, and the nodes on the chain include construction units, supervision units, construction units, material suppliers, and engineering quality supervision and management departments.

[0013] This invention also discloses a blockchain-based building material information processing system for executing the above-mentioned building material information processing method, comprising: The identifier and anchor point construction module is used to generate material twin identifiers and BIM spatiotemporal binding anchor points; The circulation verification and storage module is used to complete the compliance verification, dynamic consensus verification and on-chain storage of material circulation data; The graph construction module is used to construct a binding status graph of the entire BIM component-material chain based on a directed acyclic graph. The graph update and aggregation module is used for updating the binding status graph when the material form changes, and for cascading hash evidence storage when multi-source materials are aggregated. The traceability execution module is used to receive traceability requests and complete the full-link data verification, evidence retrieval, and traceability report generation.

[0014] Compared with existing technologies, this invention has the following advantages: By constructing material twin identifiers and BIM spatiotemporal binding anchors, this invention achieves a unique binding between the physical entity and digital identity of building materials and a dual spatiotemporal compliance verification of the flow process, effectively solving the problems of disconnected identity identifiers and easily tampered data in traditional material management; relying on the binding state graph built by the directed acyclic graph, it can perform differentiated processing for material form changes and multi-source aggregation scenarios, and combined with the cascaded hash evidence storage mechanism, it breaks through the traceability breakpoints after the irreversible aggregation of multi-source materials, ensuring the complete and coherent traceability link throughout the entire life cycle; through dynamic consensus weight allocation and multi-party signature verification mechanism, it ensures the authenticity and reliability of data while being compatible with manual input, and the entire process relies on smart contracts for automatic execution. The system architecture is lightweight, the deployment and maintenance costs are low, and it can adapt to the real-time application needs of engineering site terminals, ultimately realizing the reliable control of the entire process of building materials, rapid location of quality problems, and accurate identification of responsible parties, greatly improving the standardization and intelligence level of building engineering material management and the efficiency of engineering quality supervision. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0016] Figure 1 This is a schematic flowchart of a blockchain-based method for processing building material information according to the present invention. Figure 2 This is a schematic diagram of the structure of a blockchain-based building material information processing system according to the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In the context of full lifecycle management of building materials, problems such as the disconnect between material identification and physical entity, lack of reliable verification mechanism for circulation data, broken traceability links after irreversible aggregation of multi-source materials, and difficulty in accurately defining the responsible parties seriously affect the reliability and efficiency of project quality control, compliance supervision, and dispute resolution.

[0019] Currently, blockchain- or BIM-based methods for processing building material information have several shortcomings. Existing methods generally fail to distinguish between material form changes and multi-source aggregation scenarios, making it impossible to achieve complete traceability from the target component to the original material after irreversible mixing of multi-source materials. Furthermore, material flow data largely relies on manual entry or centralized storage, lacking effective spatiotemporal compliance verification and multi-party trusted verification mechanisms. This makes the data susceptible to tampering and its authenticity difficult to guarantee, hindering the system's ability to maintain stable traceability performance in complex construction environments. In addition, existing solutions are mostly heavy-duty system architectures, resulting in high deployment and maintenance costs, limiting real-time application on engineering site terminals and lightweight equipment.

[0020] To this end, the present invention provides a blockchain-based method and system for processing building material information. By organically integrating the immutability of blockchain, the spatial and temporal management capabilities of BIM, and the efficient traceability advantages of directed acyclic graphs, and on the basis of allowing manual input, the method solves the problem of data authenticity and credibility caused by manual input through multi-party signature verification and cascaded hash evidence storage mechanism, and realizes differentiated processing and full-link traceability in scenarios of material form change and multi-source aggregation.

[0021] This invention discloses a blockchain-based method for processing building material information. (See also...) Figure 1 As shown, the method includes: Step S1: Assign physical anti-counterfeiting codes and blockchain digital identifiers to building materials, and form material twin identifiers after hash binding; extract the three-dimensional spatial coordinate set and planned construction time window of the BIM component unit bound to the material twin identifier to form BIM spatiotemporal binding anchor points.

[0022] First, the initial construction steps of a blockchain-based building material information processing method are implemented. Each building material is assigned a corresponding physical anti-counterfeiting code, and a matching blockchain digital identifier is generated. The physical anti-counterfeiting code and the blockchain digital identifier are then hash-bound to form a unique material twin identifier. The physical anti-counterfeiting code is a unique identifier corresponding one-to-one with the building material and can be any of the following: QR code, RFID tag, or NFC tag. The blockchain digital identifier is uniformly generated by the genesis management node of the engineering consortium blockchain. The code contains a unique project code, material category code, batch code, and serial number. The serial number within a single project cannot be repeated, ensuring global uniqueness. Only the genesis management node has the authority to generate the identifier; other nodes can only perform reading and verification operations, effectively avoiding duplicate code assignment. The hash binding process uses the national cryptographic standard SM3 irreversible hash calculation. The unique serial number of the physical anti-counterfeiting code and the blockchain digital identifier are concatenated into a string, and then the SM3 algorithm is used to complete the calculation, generating a globally unique material twin identifier. This material twin identifier is bound one-to-one with all data throughout the entire lifecycle of the building material, serving as a unique identity credential for the entire material traceability process.

[0023] Simultaneously, a mapping and binding relationship is established between material twin identifiers and BIM component units, supporting a one-to-many binding scenario where one BIM component unit corresponds to multiple material twin identifiers. Each material twin identifier independently matches the corresponding BIM component unit information. The BIM component unit information bound to the material twin identifier is extracted to obtain the complete boundary coordinate set of the BIM component unit under the project's unified engineering coordinate system. Simultaneously, the planned construction time window for building materials is determined, including the planned arrival time and the planned construction time. The three-dimensional spatial coordinate set and the planned construction time window together constitute a BIM spatiotemporal binding anchor point. The three-dimensional spatial coordinate set serves as the spatial compliance benchmark for material flow, and the planned construction time window serves as the temporal compliance benchmark for material flow. Together, they form a "spatiotemporal dual verification" benchmark. This BIM spatiotemporal binding anchor point is the sole pre-verification benchmark for the compliance verification of building material flow. After binding, it is locked on the blockchain and cannot be unilaterally tampered with.

[0024] It should be clarified that the building materials mentioned in this embodiment are the smallest units of building materials, that is, the smallest material units that can be independently traced in a construction project, such as single-bag packaged materials, single-section molded profiles, single batch of prefabricated parts, etc.

[0025] Step S2: In the business flow of building materials, collect and process the corresponding business data and real-time trajectory data, and compare the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point; when the deviation is within the preset threshold, dynamically allocate consensus weights according to node attributes and perform multi-party signature verification. After the verification is passed, generate the status flow certificate of this step and store it on the blockchain.

[0026] In this embodiment, the business flow of building materials includes key nodes throughout the entire process, such as material entry, warehousing, transfer, and construction use. The corresponding business data and real-time trajectory data are collaboratively collected by each participating node in the engineering alliance chain. The business data includes core data such as material flow node information, operator information, and handover records. Real-time trajectory data is collected through positioning devices on material-carrying equipment and on-site RFID / NFC scanning devices to ensure the real-time nature and accuracy of data collection. After collection, the real-time trajectory data undergoes standardization processing. Specifically, the collected real-time trajectory data (latitude and longitude coordinates) is converted into a unified project coordinate system consistent with the BIM spatiotemporal binding anchor points using a seven-parameter conversion algorithm based on the project benchmark points. Within the planned construction time window, the converted trajectory points are clustered to obtain a set of trajectory points within that time window. The trajectory point set is compared with the complete boundary coordinate set of the BIM component unit to calculate the proportion of trajectory points falling within the component's spatial range, or the minimum spatial distance from a trajectory point to the component boundary, serving as the quantitative basis for deviation comparison. Specifically, spatial deviation is calculated using Euclidean distance, and the overall deviation is obtained through a spatiotemporal weighted formula. The formula for spatial deviation is: ;in, These are the three-dimensional coordinates of the material trajectory points in the project's unified engineering coordinate system. This is the set of boundary coordinates for BIM component elements. Let i be the coordinate point of the boundary set. This represents the minimum spatial distance from the trajectory point to the component boundary. The formula for the overall deviation is: ;in, Spatial weighting coefficients (range of values) (It can be set to 0.6 according to the actual situation of the project). To preset the spatial deviation threshold, This is the difference between the actual material turnover time and the planned construction time window. To determine the duration of the planned construction window, Comprehensive deviation (range of values) ),when (like At that time, the material flow is judged to be compliant.

[0027] After completing the real-time trajectory data processing, the system automatically compares the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor points. The preset deviation thresholds are set according to the construction accuracy requirements of building engineering in different scenarios. Specifically, the spatial deviation threshold is set to ±5cm for prefabricated components and ±20cm for bulk materials; the temporal deviation threshold is set to ±24 hours for critical path materials and ±72 hours for non-critical path materials. Those skilled in the art can flexibly adjust these thresholds according to the actual scenario. When the deviation is within the preset threshold, the material flow is deemed compliant, and consensus weights are dynamically allocated according to node attributes. Specifically, consensus weights are dynamically allocated to consortium chain nodes such as the construction unit, supervision unit, construction unit, material supplier, and third-party testing agency according to the responsibility priority and relevance of the business flow links. The total weight of all nodes in a single link is 100%. Among them, the supervision unit with the highest responsibility priority has a weight of no less than 40%, the construction unit has a weight of no less than 30%, and the remaining nodes are allocated the remaining weight according to the relevance of the links. The effective threshold for multi-party signature verification is that the cumulative signature weight ratio is no less than 80%. Once the threshold is reached, the verification is deemed successful.

[0028] After weight allocation, a multi-party signature verification operation is performed. All associated nodes corresponding to this flow link complete digital signatures sequentially within a preset time limit. The signature information is bound to the node identifier and flow time to ensure the validity and traceability of the verification. If the cumulative signature weight reaches the effective threshold of 80%, the verification is deemed successful. If the cumulative signature weight does not reach the threshold within the preset time limit, or if core responsible nodes such as the supervision unit and construction unit refuse to sign, the verification is deemed unsuccessful, the data on-chain notarization request is rejected, and the verification failure information is simultaneously pushed to all associated nodes. The verification process can be re-initiated after the objection is resolved. After successful verification, the system automatically generates a status flow certificate for this business flow link. The certificate contains core content such as material twin identifiers, flow node information, deviation verification results, and multi-party signature information. After generation, it is immediately uploaded to the engineering consortium blockchain to complete the notarization. The notarized data is tamper-proof and can be retrieved and verified at any time.

[0029] It should be noted that when the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point exceeds the preset threshold, the system will automatically trigger a compliance warning. Specifically, this includes locking the subsequent business flow permissions of the corresponding building material, rejecting the current request for data on-chain storage, synchronizing the deviation anomaly data and the corresponding material twin identifier to the blockchain supervision node, and pushing the warning information to the responsible entity of the business link so as to promptly investigate anomalies and rectify deviations.

[0030] Step S3: Using the unit project of the building project as the root node, the BIM component unit as the end node, and the building material as the leaf node, construct the binding status map of the entire BIM component-material link based on the directed acyclic graph.

[0031] In this embodiment, a binding status graph of the entire BIM component-material chain is constructed. The core purpose is to realize the full-chain association of building materials from raw materials to BIM component units, providing visual and traceable graph support for subsequent material form changes, multi-source aggregation updates, and traceability queries. This binding status graph is constructed based on a directed acyclic graph to avoid cyclic associations between nodes, ensuring the clarity and uniqueness of the traceability chain.

[0032] Specifically, the binding status map uses the unit project of the building construction project as the root node. The root node corresponds to the core unit of the entire building construction project and is the top-level node of the map. Based on the root node, sub-project nodes, itemized project nodes, BIM component unit end nodes, and building material leaf nodes are set up in descending order. The nodes at each level form a top-down hierarchical relationship, consistent with the hierarchical division of building construction management, which facilitates the quick location of the corresponding nodes by all parties involved in the project. Among them, sub-project nodes correspond to the main sub-projects in the building construction project, itemized project nodes correspond to the specific items under the sub-projects, BIM component unit end nodes correspond to specific construction components, and building material leaf nodes correspond to each smallest unit of building material. Each leaf node is uniquely bound to the corresponding material twin identifier.

[0033] Nodes at each level are connected via unidirectional, irreversible directed edges. These edges point from upper-level nodes to lower-level nodes: the root node points to a sub-project node, the sub-project node points to a sub-item node, the sub-item node points to the end node of a BIM component unit, and the end node of a BIM component unit points to a leaf node of building materials. This ensures the irreversibility of material flow and ownership relationships, aligning with the core immutability of blockchain. Furthermore, each directed edge contains explicit attribute information, including node binding time, the hash value of the corresponding material twin identifier, and the digital signature of the associated node. The node binding time records the specific moment each node establishes a connection; the hash value of the material twin identifier links the graph node to the blockchain-stored data; and the digital signature of the associated node ensures the legitimacy and trustworthiness of the node connection. All attribute information is synchronously stored on the blockchain and cannot be unilaterally altered.

[0034] It should be noted that the construction of the binding status map is triggered automatically by the map construction module after the material twin identifier is bound to the BIM component unit, without manual intervention. After completion, it is synchronized to all nodes of the engineering consortium chain in real time, ensuring that the map data obtained by all participants is consistent. After the map is built, it can be updated in real time. Subsequent operations such as material form changes and multi-source aggregation will be updated on this map accordingly, always keeping the map consistent with the actual flow and processing status of materials, providing a precise node association foundation for subsequent full-chain traceability.

[0035] Step S4: When building materials undergo shape changes or processing and assembly, the directed edges of the binding state graph are updated synchronously; when multiple source materials are aggregated into a single target component, a node aggregation operation is performed in the binding state graph, the directed edges of the corresponding leaf nodes are pointed to the same target end node, the state flow vouchers of each source material are cascaded hash calculation, an aggregated storage hash is generated and anchored to the target end node.

[0036] In this embodiment, the core objective of step S4 is to achieve real-time synchronization between the binding state map and the actual processing and circulation status of building materials. This ensures that regardless of changes in material form or multi-source aggregation, the entire traceability chain remains complete and traceable, meeting the core requirements for full lifecycle management of materials. This step performs differentiated map update operations for the two core change scenarios of building materials, ensuring both the accuracy of the map and the immutability of blockchain.

[0037] Specifically, when building materials undergo shape changes or processing / assembly—that is, when the physical form of the material changes but its independent identity remains unchanged (such as rebar cutting, formwork drilling, precast component surface processing, or simple assembly that can still be disassembled)—the system will synchronously update the directed edges of the corresponding nodes in the binding state graph. It should be noted that the directed edge update operation must be verified by multiple parties in the corresponding business process before execution. The verification process is consistent with the multi-party signature verification logic in step S2, with signature confirmation completed by related nodes such as the construction unit, supervision unit, and construction unit to ensure the legality and credibility of the update operation. The updated directed edges will synchronously update attribute information such as the node binding time and the hash value of the corresponding material twin identifier. After the update, the data is immediately uploaded to the blockchain for notarization, ensuring the immutability of the graph data. Simultaneously, historical association records before the material shape change are retained, ensuring that the original state of the material can be traced during traceability.

[0038] When multiple materials are aggregated into a single target component, that is, when multiple independent building materials undergo irreversible processing and merge to form a new BIM component unit (such as cement, sand, gravel, and water aggregated to form a concrete component, or steel bars, stirrups, and steel plates aggregated to form a steel component), the system automatically collects the physical anti-counterfeiting code information of building materials entering the same processing equipment / workstation through IoT sensing devices (such as RFID / NFC readers, workstation positioning gateways, and material carrying pallet positioning tags) deployed on processing equipment (such as mixers) or construction workstations. When the physical anti-counterfeiting codes corresponding to multiple material twin identifiers are continuously collected by the sensing devices of the same processing equipment / workstation within a preset time window and match the target component information of the current construction batch, the system automatically determines it as a multi-source material aggregation event, and the node aggregation operation can be triggered without manual input.

[0039] The specific operation process is as follows: all the leaf nodes corresponding to all building materials participating in the aggregation have their unidirectional irreversible directed edges adjusted to point to the same target end node. This target end node is the BIM component unit node corresponding to the single target component formed after aggregation, realizing the unique association between multi-source materials and target components.

[0040] Simultaneously, cascaded hash calculations are performed on the status flow vouchers of each source material. The calculation process strictly follows the business flow sequence of each source material, executing iterative irreversible hash calculations: The hash value of the status flow voucher of the first source material is used as the initial iteration value. This hash value is concatenated with the hash value of the status flow voucher of the next source material, and then substituted into the national cryptographic SM3 algorithm to calculate an intermediate hash value. This intermediate hash value is then concatenated with the voucher hash values ​​of subsequent source materials, and the SM3 calculation is repeated, thus completing the chain-like iterative calculation and ultimately generating a globally unique aggregated evidence hash. The above cascaded hash calculation can be represented as: ;in, The hash value of the status flow voucher for the i-th source material ( ), Aggregate event metadata (including target component ID, aggregation time, construction station ID, etc.). This represents a string concatenation operation. It uses the national cryptographic standard SM3 irreversible hash algorithm. This is the final generated aggregated evidence hash. This chained iterative structure ensures that any tampering with the transfer documents or aggregated metadata of any source material will result in a change to the final aggregated evidence hash. To ensure the immutability of traceability data from a technical perspective, the generated aggregated evidence hash is directly anchored to the target end node and bound to its identification information, achieving a unique association between the aggregated evidence hash and the target component. This aggregated evidence hash integrates the flow evidence information of all source materials. When tracing the target component later, the integrity of the flow data of all source materials can be verified through this aggregated evidence hash, solving the problem of broken traceability chains after the aggregation of multiple source materials.

[0041] Understandably, both node aggregation and cascading hash calculations are executed automatically by the system without manual intervention. Upon completion, the aggregation operation record, cascading hash calculation results, and target end-node update information are synchronized to all nodes in the engineering consortium blockchain, ensuring consistency in the graph data obtained by all participants. Furthermore, the aggregated source material leaf nodes are not deleted; their relationships are bound to the target end-nodes via directed edges. This preserves the full lifecycle data of the source materials while achieving a complete link between the target component and the source materials, providing comprehensive data support for subsequent traceability queries.

[0042] Step S5: When a traceability request for the target building component is received, the corresponding node in the binding status graph is located by the BIM component unit ID. The depth of the reverse edge of the directed acyclic graph is traversed, the aggregated evidence hash and digital signature integrity of the nodes along the way are verified, and the full-link evidence data is extracted.

[0043] In this embodiment, the core objective of step S5 is to achieve full-chain traceability of the target building component from the aggregated finished component to the original building material, quickly locate the entire process information of material flow, processing, and aggregation, and provide tamper-proof evidence support for quality problem investigation, compliance auditing, and responsibility determination. The execution entity of this step is the system's traceability execution module. The entire process is automatically completed through smart contracts pre-deployed on the blockchain without human intervention, ensuring traceability efficiency and data credibility.

[0044] Specifically, when the system receives a traceability request for a target building component, the traceability request can be initiated by any node in the engineering consortium chain. The initiating entities include construction units, supervision units, construction units, regulatory departments, etc. The types of traceability requests include traceability of quality issues, traceability of compliance audits, and traceability of materials throughout the entire supply chain. The request must contain a clear BIM component unit ID, which is the unique identifier of the BIM component unit corresponding to the target building component and serves as the core basis for traceability and positioning.

[0045] Upon receiving a traceability request, the system first uses the BIM component unit ID carried in the request to quickly locate the corresponding target end node in the binding status graph, i.e., the node corresponding to the BIM component unit. The location process relies on the hierarchical relationship of the graph to achieve accurate and rapid matching, ensuring that the location is without deviation. After the location is completed, the system performs a depth-first traversal operation along the reverse edge of the directed acyclic graph. The traversal terminates when the root node of the unit project is reached upwards and all associated building material leaf nodes are reached downwards. The traversal direction is opposite to the forward association direction when the graph was constructed, i.e., from the target end node (BIM component unit), the system traverses the sub-item project node, sub-section project node, and unit project root node upwards in sequence, while simultaneously tracing downwards in reverse to all source material leaf nodes associated with the BIM component unit. If the BIM component unit is formed by the aggregation of multiple source materials, the system will simultaneously trace the leaf nodes corresponding to all source materials participating in the aggregation and the full-link association nodes of each source material.

[0046] During the traversal, the system simultaneously verifies the aggregated evidence hash and digital signature integrity of all nodes along the path to ensure the authenticity and immutability of the traced data. The verification logic for the aggregated evidence hash is as follows: the aggregated evidence hash obtained during the traversal is compared with the corresponding node's aggregated evidence hash recalculated by the system. If they match, the aggregated evidence hash is deemed complete and valid. The digital signature verification uses the public key of the engineering consortium blockchain node to decrypt and verify the digital signature of each node along the path, confirming that the signature was genuinely signed by the corresponding node and that there was no forgery or tampering. It should be noted that if any anomalies such as aggregated evidence hash mismatch or invalid digital signatures are found during the verification process, the system will immediately terminate the tracing operation, push a verification anomaly notification, and synchronize the anomaly information to the blockchain monitoring node to facilitate investigation of the cause of the data anomaly.

[0047] After successful verification, the system automatically extracts end-to-end evidence data from all nodes along the route. The extracted data covers the entire lifecycle information of the target building components and their corresponding source materials, specifically including material twin identifiers, physical anti-counterfeiting codes, BIM spatiotemporal binding anchor point data, status transition vouchers for each business process, form change records, node aggregation operation records, cascade hash calculation results, and digital signature information from all parties. All extracted evidence data is directly retrieved from the engineering consortium blockchain, ensuring the immutability and integrity of the data.

[0048] Understandably, after the end-to-end evidence data is extracted, the system will automatically locate the business process, responsible entity, and supporting documentation corresponding to the traceability request based on the extracted data, generating an immutable material lifecycle traceability report. This report can be simultaneously pushed to the node that initiated the traceability request and all relevant nodes in the consortium blockchain, facilitating viewing and verification by all participants. The entire traceability process is highly efficient and fast. From receiving the request to extracting the data and generating the report, the entire process is automatically executed by smart contracts, ensuring the accuracy of the traceability results and significantly improving traceability efficiency. This solves the industry pain points of complex, time-consuming, and unreliable documentation in traditional building material traceability processes.

[0049] Accordingly, this invention also discloses a blockchain-based building material information processing system, which includes an identification and anchor point construction module, a circulation verification and evidence storage module, a graph construction module, a graph update and aggregation module, and a traceability execution module. See [link to relevant documentation]. Figure 2 As shown, specifically: The identifier and anchor point construction module is used to generate material twin identifiers and BIM spatiotemporal binding anchor points; The circulation verification and storage module is used to complete the compliance verification, dynamic consensus verification and on-chain storage of material circulation data; The graph construction module is used to construct a binding status graph of the entire BIM component-material chain based on a directed acyclic graph. The graph update and aggregation module is used for updating the binding status graph when the material form changes, and for cascading hash evidence storage when multi-source materials are aggregated. The traceability execution module is used to receive traceability requests and complete the full-link data verification, evidence retrieval, and traceability report generation.

[0050] Each module corresponds to a step of a blockchain-based building material information processing method, working together to achieve trusted identification, compliant circulation, map management, and full-chain traceability of building materials throughout their entire lifecycle, meeting the actual application needs of engineering sites.

[0051] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A blockchain-based method for processing building material information, characterized in that, Includes the following steps: Physical anti-counterfeiting codes and blockchain digital identifiers are assigned to building materials, and after hash binding, material twin identifiers are formed; the three-dimensional spatial coordinate set and planned construction time window of the BIM component unit bound to the material twin identifier are extracted to form BIM spatiotemporal binding anchor points; In the business flow of building materials, the corresponding business data and real-time trajectory data are collected and processed, and the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point is compared. When the deviation is within the preset threshold, consensus weights are dynamically allocated according to node attributes and multi-party signature verification is performed. After the verification is passed, the status flow certificate of this link is generated and stored on the blockchain. Using the unit project of the building project as the root node, the BIM component unit as the end node, and the building material as the leaf node, a binding state map of the entire link of BIM component-material is constructed based on the directed acyclic graph. When building materials undergo shape changes or processing and assembly, the directed edges of the binding state graph are updated synchronously. When multiple source materials are aggregated into a single target component, a node aggregation operation is performed in the binding state graph. The directed edges of the corresponding leaf nodes are pointed to the same target end node. The state flow certificates of each source material are subjected to cascade hash calculation to generate an aggregated evidence hash and anchor it to the target end node. When a traceability request for a target building component is received, the corresponding node in the binding status graph is located by the BIM component unit ID. The system then performs a depth-first traversal along the reverse edge of the directed acyclic graph, verifies the aggregated evidence hash and digital signature integrity of the nodes along the way, and extracts the full-link evidence data.

2. The blockchain-based building material information processing method according to claim 1, characterized in that, The physical anti-counterfeiting code is a unique identifier that corresponds one-to-one with building materials, including any one of QR codes, RFID tags, or NFC tags; the hash binding is to perform irreversible hash calculation between the unique serial number of the physical anti-counterfeiting code and the blockchain digital identifier to generate a globally unique material twin identifier; the material twin identifier is bound one-to-one with all data of the building material throughout its entire life cycle; the three-dimensional spatial coordinate set is the complete boundary coordinate set of BIM component units under the unified engineering coordinate system of the project; The planned construction time window includes the planned arrival time of building materials and the planned construction time; the BIM spatiotemporal binding anchor point is the only prerequisite verification benchmark for verifying the compliance of building material circulation.

3. The blockchain-based building material information processing method according to claim 1, characterized in that, The processing of the real-time trajectory data is specifically as follows: The real-time trajectory data is converted into a unified engineering coordinate system consistent with the BIM spatiotemporal binding anchor points using a seven-parameter conversion algorithm for project benchmark points. Cluster the converted trajectory points within the planned construction time window to obtain the trajectory point set within that time window; The trajectory point set is compared with the complete boundary coordinate set of the BIM component unit to calculate the proportion of trajectory points falling within the component's spatial range, or the minimum spatial distance from the trajectory point to the component boundary, which serves as the quantitative basis for subsequent deviation comparison.

4. The blockchain-based building material information processing method according to claim 1, characterized in that, When the deviation between the real-time trajectory data and the BIM spatiotemporal binding anchor point exceeds a preset threshold, a compliance warning is triggered. The compliance warning includes: locking the subsequent business flow permissions of the corresponding building materials, rejecting the current request for data on-chain evidence storage, synchronizing the deviation and abnormal data and the corresponding material twin identifier to the blockchain supervision node, and pushing the warning information to the responsible entity of the corresponding business link.

5. The blockchain-based building material information processing method according to claim 1, characterized in that, The dynamic allocation of consensus weights based on node attributes specifically involves dynamically assigning corresponding consensus weights to nodes such as the construction unit, supervision unit, construction unit, material supplier, and third-party testing agency based on the responsibility priority and correlation of the business process.

6. The blockchain-based building material information processing method according to claim 1, characterized in that, The binding status diagram of the entire BIM component-material link is set with the unit project as the root node, and then set down to sub-project nodes, sub-item project nodes, BIM component unit end nodes, and building material leaf nodes. The nodes at each level are associated with each other through unidirectional irreversible directed edges. The attributes of the directed edges include the node binding time, the hash value of the corresponding material twin identifier, and the digital signature of the associated node.

7. The blockchain-based building material information processing method according to claim 1, characterized in that, The directed edge update of the binding state graph must be verified by multiple parties in the corresponding business process before it can be executed; the cascaded hash calculation is specifically as follows: according to the business flow sequence of each source material, the hash values ​​of the state flow vouchers of all source materials are concatenated and iterative irreversible hash calculation is performed to generate a globally unique aggregated evidence hash.

8. The blockchain-based building material information processing method according to claim 1, characterized in that, The traceability request includes traceability of quality issues, traceability of compliance audits, and traceability of materials throughout the entire supply chain. After extracting the evidence data of the entire supply chain, the process also includes: locating the business process, responsible entity, and supporting documentation corresponding to the problem based on the evidence data of the entire supply chain, and generating an unalterable traceability report of the entire life cycle of materials.

9. The blockchain-based building material information processing method according to any one of claims 1 to 8, characterized in that, The deviation comparison, consensus weight allocation, multi-party signature verification, binding state graph update, cascade hash calculation, and tracing traversal operation are all automatically executed through smart contracts pre-deployed on the blockchain; the blockchain is an engineering consortium blockchain, and the nodes on the chain include construction units, supervision units, construction units, material suppliers, and engineering quality supervision and management departments.

10. A blockchain-based building materials information processing system, characterized in that, A method for processing building material information based on blockchain as described in any one of claims 1 to 9, comprising: The identifier and anchor point construction module is used to generate material twin identifiers and BIM spatiotemporal binding anchor points; The circulation verification and storage module is used to complete the compliance verification, dynamic consensus verification and on-chain storage of material circulation data; The graph construction module is used to construct a binding status graph of the entire BIM component-material chain based on a directed acyclic graph. The graph update and aggregation module is used for updating the binding status graph when the material form changes, and for cascading hash evidence storage when multi-source materials are aggregated. The traceability execution module is used to receive traceability requests and complete end-to-end data verification, evidence retrieval, and traceability report generation.

Images