Large Bridge Research Articles

Probabilistic anomaly detection considering multi-level uncertainties for cable-stayed bridges

To model multi-level uncertainties within anomaly detection process for large-span bridges, a probabilistic anomaly detection method is proposed considering uncertain models in the data collection, thermal response separation, and trigger estimation. The uncertain model in the data collection is established with the measured value and measuring errors. The uncertain model in the thermal response separation is built through the linear Bayesian estimation. The uncertain distribution of the anomaly detection trigger is obtained via Bayesian estimation of generalized Pareto distribution. Subsequently, measurements from multi-sensors are used to detect anomalies in a probabilistic way. Evidential reasoning, a decision-level fusion tool, is used to derive a collective detection rate to distinguish sensor malfunctions from anomalous scenarios. Specifically, anomalous scenarios deserve a large collective detection rate, whilst sensor malfunctions are subject to a small collective detection rate and a large individual detection rate. Two cases (i.e., sensor malfunction and snow disaster) are illustrated based on measurements from a large span cable-stayed bridge. As a result, the sensor malfunction is detected with an individual detection rate of 89.20% and a collective detection rate of 2.77%. The snowstorm is detected by a collective detection rate of almost 100%.

Equivalent conversion investigation of environmental corrosion of suspenders in long-span suspension bridge

Purpose This paper aims to investigate the equivalent relationship between accelerated corrosion tests and real environmental spectrum of suspenders in long-span suspension bridge considering multiple factors action. Design/methodology/approach Based on Faraday's law, corrosion current was used as a measure of metal corrosion, and the equivalent conversion relationship between laboratory environment and real service environment was established. The equivalent conversion method for bridge structural steel had been determined under different temperature, humidity, pH value and NaCl concentration conditions. The compilation of environmental spectra for large span bridges considering multiple factors and the principle of equivalent conversion have been proposed. Findings Environmental factors, including temperature, humidity, pH value and NaCl concentration, have significant impact on the corrosion degree of suspension steel wires, and only considering these two factors for equivalent conversion cannot accurately reflect the true service environment of the bridge. The 33.8-h salt spray accelerated corrosion test using the standard conditions can be equivalent to one year of suspenders corrosion in a real service environment. Originality/value The equivalent accelerated corrosion method for steel wires proposed in this study can effectively predict the corrosion degree of the suspenders, which has been verified to be correct and can provide theoretical guidance for the development of corrosion test plans for steel wires and engineering technical basis for anti-corrosion control and calendar life research of suspension bridge suspenders.

A Review of the Network Arch Bridge

The network arch bridge (NAB) is a new structural form of arch bridge that was devised 60 years ago by the Norwegian engineer Per Tveit, who is now prof. dr. docent emeritus at the University of Agder, Norway. The network arch is a tied-arch (also known as a bowstring-arch) bridge that combines the benefits of tied-arch bridges and trusses in a single system. While in a classical tied arch, the hangers are vertical, in a network arch, the suspension of the deck to the arch is ensured through a network of inclined hangers that intersect each other at least twice. Thus, the core of the NAB is the hanger arrangement that minimizes the bending moment in the arch to very small values, leading to compression in the arch. Compression with only small bending leads to very slender cross-sections for the elements of the bridge, and deep reductions in terms of materials used and economic and environmental costs. This paper reviews the research into the structural form proposed by Per Tveit and extended by researchers and engineers worldwide. The research methodology included bibliometric literature research, obtained by interrogating the ISI Web of Science (WoS) database and the cited references from the articles on WoS. While the first structural form of a network arch is still in use today and it has proven to be a good idea for spans around 100–120 m, engineers worldwide devised new bridge cross-sections. A brief view of the types of bridge cross-section in use today is given, with details about the bridges chosen as representative. Using analysis of Prof. Tveit’s map, Structurae database and literature review, a database of the network arches around the world was created, emphasizing the development of network arches from the perspectives of continental distribution, opening year, number of structures in different structural forms, and bridge purposes. The structural form was assessed from the perspective of materials used for the arch and the tie, span, purpose and number of lanes, the presence/absence of upper wind-bracings and arch disposition in the vertical plane. In the last part of this review, the newest research into the development of the network arch is discussed. In the past 15 years we have seen an acceleration in network arch development from multiple perspectives: new materials used, such as glulam for the arch or carbon fiber-reinforced plastic for the hangers; span lengths of 250 m and 380 m for large bridge widths; architectural constraints that lead to the outward inclination of the arch, that is pleasing to the eye, but difficult to address from an engineering perspective; the most slender arch bridge in the world, with very slender cross-sections for the arch and the tie.

ZAŠTITA TEMELJNE JAME STUPNOG MJESTA S2, PRI IZGRADNJI MOSTA POČITELJ

In the last few years, the construction works on Počitelj Bridge, the largest giant of the Corridor Vc, have been executed. Počitelj Bridge connects two banks of the “divine” (as named by the Illyrians) river Neretva, thus connecting Bosnia and Herzegovina with Croatia and Hungary. The Počitelj bridge is being built north from the town having the same name - Počitelj. Its length of about 980 m and height of about 100 m above the river make it the largest bridge in Bosnia and Herzegovina. It consists of seven spans, i.e. six middle pillars and two abutments. The subject of this paper is a review of the construction of the foundation at the S2 pillar location using analyses and comparisons with the main project, especially the protection of the construction pit during the works execution at the above-mentioned pillar location.

Construction Risk Assessment of Yellow River Bridges Based on Combined Empowerment Method and Two-Dimensional Cloud Model

(1) In recent years, the economy of the Yellow River basin in China has developed rapidly, and a series of large bridges across the Yellow River have been built on both sides of the Yellow River, which has brought great convenience to regional socio-economic activities. However, risk events are prone to occur during the construction of bridges across the Yellow River, which affect the safety of the bridges’ structure. Therefore, it is necessary to establish a new scientific risk assessment system for the construction safety of bridges across the Yellow River. (2) Methods: Firstly, based on the construction safety risk assessment index system of bridges across the Yellow River, the cloud AHP method and the cloud entropy weight method are used to determine the subjective weight and objective weight of risk indexes, and then the game theory combination weighting method is used to determine the comprehensive weight of each risk index, and then the digital characteristic values of the risk probability cloud and the consequence cloud are calculated and input into the forward cloud generator algorithm. MATLAB was used to generate a two-dimensional comprehensive cloud map, which was visually compared with the standard cloud map, and the probability level and consequence level of each risk index were preliminarily obtained. Finally, the risk assessment matrix was used for comprehensive risk evaluation. (3) Results: Applying the method to the construction safety risk assessment of the Jiaoping Expressway, the overall construction safety risk level of the Yellow River bridge was determined as level 4, and the risk levels of the four primary indicators were: personnel risk (level 3), material and equipment risk (level 4), construction technology risk (level 5), and construction environment risk (level 4). (4) Conclusions: The results of the risk evaluation are consistent with the actual construction state of the bridge, which shows that game theory’s combination of empowerment with a two-dimensional cloud model is scientific and effective when applied to the construction safety risk evaluation of Yellow River bridges.

Exploratory Test of Horizontal Drilling Plugs and Water Shutoff Technology in X Horizontal Gas Well

In order to solve the problem that the tight gas X horizontal gas well could not be put into production due to the accumulation of fluid in the wellbore during the drainage stage after fracturation, based on the geological understanding of water flowing from the far end of the reservoir, and the actual situation of staged fractured with drillable bridge plug, water blocking has become the exploration direction of potential excavation and resuming production. Through the analysis of the type, structure, setting principle and unsealing principle of drillable bridge plug, put forward the technical idea of horizontal drilling plugs and mechanical water plugging. And determine the treatment method of drilling-grinding and fishing large inner diameter bridge plugs, and design the construction process. Moreover combined with theoretical calculation, the relationship between the debris carrying velocity and displacement in horizontal wells, the size of the debris and the angle of inclination was optimized. Besides that, the milling method that uses a wellhead rotating device to drive the drill pipe and grinding shoes for drilling and grinding was proposed. In the field test, successfully drill to the third large inner diameter bridge plug position according to the design requirements. And successfully put in the fishable bridge plug to achieve mechanical water blocking. After commissioning, the daily gas production volume reached 11000 m3/d. The test results show that: 1) It is feasible to use the wellhead rotating drive drill pipe and grinding shoes to drill and remove the steel drillable bridge plugs in the horizontal section of the horizontal well; 2) It is also feasible to use the fishable bridge to plug in the horizontal section of the horizontal gas well with drillable bridge plug staged fractured, and the plugging effect is good. In summary, it is shown that this technology test achieves the purpose of potential excavation and resuming production of the X horizontal gas well, which has good reference value.

Discovering key factors and causalities impacting bridge pile resistance using Ensemble Bayesian networks: A bridge infrastructure asset management system

Bridges are one of the critical infrastructure systems and play a critical role in supporting the economic development of nations. During the planning, design, and construction phases of bridges, it is important to ensure that the different bridge components satisfy the desired performance for avoiding catastrophic failure. One example is the foundation system with deep driven piles. A crucial consideration when planning, designing, and constructing bridge foundation system is to accurately estimate the pile resistance (i.e., capacity). However, this process constitutes a considerable challenge for bridge managers and engineers due to the uncertainties, subjectivities, and biases involved in providing accurate estimates. In fact, the current design process of bridge pile foundations is still performed in a relatively simple and deterministic manner. Thus, there is still a lack of studies that were conducted to effectively represent the causalities between different variables impacting the bridge pile resistance using objective, data-driven methods rather than subjective, expert-based methods. Therefore, this paper addresses this knowledge gap by proposing a data-driven, knowledge-discovery Bayesian network model as an expert system to (1) identify the key factors impacting the performance of bridge piles through data-driven knowledge discovery; (2) capture the causal (direct and indirect) relationships between the different variables that influence bridge pile resistance, and (3) predict bridge pile resistance in support of decision making in bridge design and construction. Multiple Bayesian network models were developed using two distinct learning paradigms based on a pile dataset with 18 variables and 2,375 data samples from a large bridge project. One paradigm is to run a regular process for learning graphical models using Bayesian structure learning, while the other one is to couple Bayesian networks with bagging ensemble learning. Model validation results showed that the best model learned by bagging ensemble learning paradigm achieves the highest prediction accuracy of 89.78% for predicting bridge pile resistance. Additionally, the developed Bayesian network models identify 8 critical factors affecting bridge pile resistance. These factors are categorized into four groups, including the external applied force on pile head, pile mechanical property (i.e., compressive stresses in bridge piles), hammer property and operation characteristics (e.g., hammer blow count), and pile cap elevation. The observations from this study would assist bridge managers and practitioners in decreasing the uncertainties that impact the estimation of pile capacity, and thus help in balancing cost-effectiveness with good performance. The paper adds to the body of knowledge by providing a great deal of insights related to the factors and causalities influencing the performance of deep bridge foundations to ultimately help in the plan, design, and construction phases of bridges.

Aerodynamic stability of high-speed vehicle passing bridge tower in different lanes under crosswind conditions

Large bridges' decks often exhibit different adhesion coefficients in complex environments, which are frequently accompanied by significant crosswind effects. This results in a complex and constantly changing flow field around vehicles, which can severely impact driving safety. In this study, the two-way coupling method is utilized to investigate the transient aerodynamic characteristics and dynamic response of vehicles passing through bridge towers at high speeds in different lanes with varied adhesion coefficients under crosswind conditions. The vehicle speed was 30 m/s, and the crosswind velocity was recorded at 11.33 m/s. The results indicate that the aerodynamic load fluctuates more significantly due to the influence of the bridge tower. In the same lane, the bridge deck with an adhesion coefficient of 0.4 produces a greater lateral displacement and yaw angle. When passing through the bridge tower, a vehicle in lane L1 is suddenly affected by vortex shedding, resulting in a larger lateral displacement and yaw angle compared to vehicles in L2 and L3 lanes. The lateral displacement measures 0.251 m, and the yaw angle measures 0.0205 radians at an adhesion coefficient of 0.4. This also indicates that driving in the L1 lane in a crosswind environment is relatively less safe.

Renovating the Van Brienenoord Bridge Steelwork in mechanical system of bascule bridge spanning 50m.

AbstractThe Van Brienenoord Bridge is a large bridge which includes three movable bascules. The two oldest bascules stem from 1965. A study into renovation and/or replacement of these bascules has been performed and replacement was deemed necessary. A new design for the mechanical driving system has been made, where the design of the western bascule served as starting point. The regulations and requirements have become more stringent since 1965, however the available space is restricted by the existing concrete structure. A steel rack and pinion design is chosen as the best option for the mechanical driving system. In the design of the steel rack, several considerations have been made with respect to the material choice. A fully welded construction was desired due to the lower weight of the construction. However, stringent requirements are made with respect to the hardness, yield strength and tensile strength in several locations of the rack. After considerable calculations and consulting suppliers/manufacturers the tooth rack will be made of 25CrMo4 as the best compromise between material properties and weldability. The pinion material is selected as 34CrNiMo6 since weldability is not an issue. The choice here has to do with the minimum required mechanical properties (even above‐normative refinement). The connection to the concrete structure consists of an eye which is rather big and bulky. This is considered to be rather conservative due to the calculations methods and leaves room for optimisation.

Probabilistic design life selection procedure for a steel bridge

AbstractNumerous bridges and viaducts built in Western Europe in the middle of the 20th century are now in service for more than 50 years. Aging and changes in societal demands result in a gradual decline of their technical and functional performance. This consequently forces responsible authorities to replace the obsolete infrastructure in the coming decades.Large‐scale renovation programs together with further development of the highway network require a lot of resources and make a significant environmental impact. The assumed design life of bridges affects structural solutions and the choice of materials. Therefore, there is an opportunity for more efficient use of resources and reduction of the environmental impact if the design life of new bridges is optimized with respect to life cycle costs and CO2 equivalent emissions.As multiple design life options exist for any bridge, it is essential to have a consistent approach capable of indicating the favorable option. Therefore, a procedure has been developed for comparison of various design life options based on lifecycle costs and lifecycle CO2 equivalent emissions. The procedure accounts for different traffic growth and traffic load development scenarios and it considers probabilities of these scenarios to happen in the future. This allows to assess the effect of uncertainty in functional parameters resulting in probabilistic lifecycle costs and emissions, which indicate a proper design life option.The procedure is applied to a large span steel bridge over a river. Two design life alternatives, namely 100 years and 200 years, are considered. This paper summarizes the results of this study and it offers a discussion on limitations and perspectives of the suggested procedure.

A New Methodology for the Prioritization of Visual Inspections of Bridges and Viaducts

AbstractThe assessment of risk conditions of bridges and viaducts allows management authorities to ensure the safety of the users and the proper allocation of economic resources for maintenance and retrofitting interventions. A common circumstance in practice regards the lack of information as well as the need to update it, causing delays in the risk evaluation and, consequently, in the entire decision‐making process. Especially in the managing of large bridge assets, the retrieval/updating of information can be costly, both in terms of time and economic resources. In this regard, the execution of visual inspections to determine the defect level of bridges and viaducts is the most resource‐intensive operation on the part of the management authorities. In this paper, a new methodology to prioritize visual inspections of bridges according to their risk condition and operating costs is proposed and illustrated with a real case study. A novel aspect of the proposed methodology regards the use of information gain criteria to refine the outcomes from the risk assessment and prioritization process. Finally, the outcomes of the methodology are implemented in a GIS framework to ensure high interoperability and facilitate the construction of intuitive risk maps to assist inspection plans.

Optimal Cable Force Adjustment for Long-Span Concrete-Filled Steel Tube Arch Bridges: Real-Time Correction and Reliable Results

For complex structures, the existing optimization method for suspender cable forces involves extensive matrix operations during the solution process, requiring high computational power and time. As a result, obtaining a more accurate solution becomes challenging. To address this issue and improve the stress distribution of suspenders in the completed state, while minimizing the need for frequent cable force adjustments and grid beam elevation changes during construction, a novel method for cable force optimization is proposed. In this study, the Pingnan Third Bridge, which is the world’s longest large span arch bridge with a span of 575 m, is taken as the engineering background. This study combines finite element analysis and multi-objective optimization methods to develop a cable force optimization approach for real-time correction during the panel girder lifting of long-span concrete-filled steel tube (CFST) arch bridges. The optimization method involves treating the panel girder weight and displacement during construction as parameter variables, and considering the displacement and unevenness of the panel girder in the completed state as constraint conditions. The objective equation is defined based on the displacement and cable force during the lifting construction process and, through optimization, the cable forces and displacements of each lifting section are calculated. The results demonstrate the feasibility of integrating optimization theory into the cable force optimization process during panel girder lifting. In this study, we have taken into account the characteristics of real-world engineering and focused on specific key points to reduce the order of the influence matrix. Consequently, the computational costs are reduced, facilitating the development of a multi-objective tension optimization program. By minimizing segment displacement variations and ensuring even cable force distribution in the completed state, the method ensures that the bridge meets the required completion requirements without the need for repetitive iterations or cumbersome calculations. It provides higher optimization efficiency and superior outcomes, offering significant value for cable force calculations during suspender construction of similar bridge types and guiding construction processes.

Experimental and Simulation Study on Welding Characteristics and Parameters of Gas Metal Arc Welding for Q345qD Thick-Plate Steel.

The welding and construction processes for H-type thick-plate bridge steel involve complex multi-pass welding processes, which make it difficult to ensure its welding performance. Accordingly, it is crucial to explore the inherent correlations between the welding process parameters and welding quality, and apply them to welding robots, eliminating the instability in manual welding. In order to improve welding quality, the GMAW (gas metal arc welding) welding process parameters are simulated, using the Q345qD bridge steel flat joint model. Four welds with X-shaped grooves are designed to optimize the parameters of the welding current, welding voltage, and welding speed. The optimal welding process parameters are investigated through thermal-elastic-plastic simulation analysis and experimental verification. The results indicate that, when the welding current is set to 230 A, the welding voltage to 32 V, and the welding speed to 0.003 m/s, the maximum deformation of the welded plate is 0.52 mm, with a maximum welding residual stress of 345 MPa. Both the simulation results of multi-pass welding, and the experimental tests meet the welding requirements, as they show no excessive stress or strain. These parameters can be applied to building large steel-frame bridges using welding robots, improving the quality of welded joints.

ANN model for predicting the elastic critical buckling coefficients of prismatic tapered steel web plates under stress gradients

Tapered steel plate girders are commonly used in large span industrial structures and composite bridges. The tapered thin steel web plates under stress gradients in such structures may be susceptible to elastic local buckling. An efficient and robust Artificial Neural Network (ANN) model is developed and presented in this paper for predicting the elastic critical buckling coefficients of prismatic tapered steel webs under stress gradients. More than 4000 samples are used in extensive parametric analyses of tapered web plates with simply supported edges. The ANN model recognizes important features associated with tapered plates, including the tapering ratio of the plate, aspect ratio, and stress gradient. A dataset containing 4665 records is developed for the training, validation, and testing of the ANN model developed. Two main ANN models are developed. The first model consists of a single hidden layer with neurons varying from 5 to 11. The second model consists of two hidden layers, with 8 neurons in the first layer and 6 neurons in the second layer. The accuracy of these models is thoroughly evaluated. It is found that the developed ANN model with two-hidden layers has superior performance than other models. The developed ANN can be employed to accurately predict the elastic critical buckling coefficients of prismatic tapered steel webs under stress gradients.

A decision-making system for large span bridge inspection intervals based on sliding window DFNN

To avoid expert inspection, this study develops a decision-making system for large-span bridge inspection intervals based on dynamic fuzzy neural networks (DFNN), which can find knowledge from existing inspection data. A sliding window is introduced to enable the system to learn incrementally so that the system can update along with the bridge degradation. Tsing Ma Bridge is adopted as a prototype bridge while its rating system established based on the fuzzy-analytic hierarchical process (Fuzzy-AHP) method is employed to generate training and testing samples. The capability of the system in finding the relationship between the rating indexes and the rating scores as well as renewing itself with the bridge degradation is then verified. And the influence of the length of the window is investigated. The research shows that the method can make accurate decisions for bridge inspection intervals after being trained by existing data.

Construction Control and Monitoring Platform of a Large-Segment Steel Box Girder with Hoisting Installation

The large-segment hoisting construction technology for bridges is increasingly widely used due to its flexibility and efficiency, although it also poses challenges to construction monitoring. Traditional monitoring technology is unitary with low data processing efficiency, making it difficult to meet the accuracy requirements of large-segment hoisting. The application of digital technology has brought about an opportunity for innovation in bridge construction monitoring technology. To address existing challenges and explore digital applications, this paper takes the integral hoisting construction control of the large-segment steel box girder in a large cross-sea bridge as an example, developing an alignment, stress, and temperature monitoring scheme by taking the key points of hoisting construction control into consideration. A monitoring platform was developed, and the workflow of large-segment hoisting construction monitoring is systematically summarized from the viewpoint of practical engineering, which provides a valuable reference for achieving precise and efficient construction monitoring and control in similar projects.

Probability-based damage thresholds for bridges’ inspection-based deterioration curves

A probability-based procedure is presented to define damage thresholds of bridges’ deterioration curves, which is applied to a large bridge database of real on-site inspections. The procedure is based on a change of variable to transform any distribution of bridge durability deterioration ratings into a normal distribution. This allows probability-based calculations of damage thresholds associated to certain criteria (e.g. Serviceability or Ultimate Limit State), for immediate application to deterioration prediction curves. This research defines a novel procedure for a probability-based analysis of inspection-based data and, de facto, provides a reliable statistical support system to traditional infrastructure management systems of bridges.

Fatigue properties of OSD in large cantilever cable-stayed bridge on highway-railway layer

To enhance the understanding of fatigue issues in orthotropic steel deck (OSD) bridges with cantilevered steel-box girders on highway–railway layers and ensure the fatigue life of similar bridges, this study focused on the OSD fatigue characteristics of the Jinhai Bridge, the world's widest dual-use–cable-stayed bridge for road and railway transport. The fatigue-stress distribution characteristics and variation rules were investigated using a full-scale fatigue test model. Four U-ribs were subjected to four million loading test cycles, and the OSD fatigue performance was evaluated using the nominal stress method. The results indicated that the stress-influence range of the crossbeam U-rib in a large cantilever steel box girder was approximately nine U-ribs wide and three crossbeams long, significantly exceeding that of a conventional closed-box steel girder. The stress difference in the crossbeam opening bottom-edge detail in the box girder with and without a cantilever was 85.4%. Along the transverse bridge, the most unfavorable stress amplitude difference among similar fatigue details in different regions reached 57%. After 4 million cycles, the crack length was 90 mm. The fatigue cracks had a minimal effect on the overall deformation performance of the model. Combining the traffic volume statistical data and damage accumulation, the estimated fatigue life of the crossbeam opening detail was 103.55 years. According to JTG-D64–2015, this satisfies the recommended fatigue design life requirement of 100 years for the crossbeam opening details of large cantilever steel box girders. However, the economic development trends and increasing traffic volumes necessitate further research.

Rotating box multi-objective visual tracking algorithm for vibration displacement measurement of large-span flexible bridges

Visual displacement measurement methods for flexible structural bodies like large-span bridges has gained wide popularity in recent years, but practical applications still have some limitations. For instance, when acquiring images of large-span flexible bridges at a distance, the slight angular tilt of the detection target due to irregular vibrations can cause extremely serious misfit errors in the displacement curves returned by the vision measurement algorithm. To improve the reliability of vibration displacement measurement of flexible structural bodies, this paper takes the bridge subjected to external excitation in the acquired image sequence as the object of vibration displacement measurement and uses a designed high-precision displacement measurement algorithm for a single-stage rotating target tracking anchor-free box to track the vibration displacement of the target in the flexible structural body. We first extract multi-scale feature information of bridge model image sequences using the improved YOLOv5-s backbone network and combine the Transformer self-attention mechanism with PANet to perform a top-down and bottom-up bi-directional fusion of target feature maps at three different scales to achieve semantic feature fusion of shallow and deep information. Second, the improved Efficient Decoupled Head performs the detection of rotating target centroid offset and bounding box size. Finally, the detected results are passed into the multi-objective tracking algorithm ByteTrack, which strengthens the spatio-temporal correlation between frames and obtains a better-fitting vibration displacement curve. The validation and comparison of traditional visual measurement methods and deep learning measurement methods on cable-stayed bridge models, small arch bridges, and large span bridges show that the vibration displacement trajectories regressed by the algorithm in this paper have the best fit with the actual vibration displacement trajectories, which also verifies that the algorithm in this paper has good potential for engineering applications and implementation space in the field of condition monitoring of flexible structural bodies.

Comprehensive Evaluation of Green Bridge Construction Based on a Game Theory–Radar Chart Combination

The construction of large bridges requires significant natural resource consumption and causes widespread environmental damage, violating the concept of sustainable development. Therefore, it is necessary to build a comprehensive evaluation system for green construction. This paper took a bridge as a research object to establish a green construction evaluation index system based on GB/T 50640-2010, the “Green Construction Evaluation Standard for Construction Projects”. A combined game theory–radar chart method was adopted to evaluate the level of green construction for five construction schemes. The results were Scheme II > Scheme IV > Scheme III > Scheme I > Scheme V, where Scheme II was the best. The evaluations in this paper were consistent with those obtained by the G1-TOPSIS method; however, a combined-assignment method was used to avoid the one-sidedness of single-assignment, and to make the evaluations more objective.