This article focuses on the overall construction duration,explaining the core role of the critical path method and its relationship with the total construction period.It analyzes the factors influencing the total cons...This article focuses on the overall construction duration,explaining the core role of the critical path method and its relationship with the total construction period.It analyzes the factors influencing the total construction duration,introduces the application of BIM and other technologies in identifying and managing critical paths,emphasizes the importance of optimizing resource allocation,and illustrates measures to address disruptions through practical examples.Additionally,it discusses the evaluation system and incentive mechanisms.展开更多
According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculatio...According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably,展开更多
A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger ...A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed.展开更多
According to the National Meeting on Power Construction and Cost Control held in Beijing on 26th August 1996, the target for power construction in the period of 9th Five- year Plan is set-up as follows:
The Supervision during construction of Thailand PTA Co-generation, Which was contracted by our country extended into the quality guaranteed period. The supervision during the quality guaranteed period includes the mon...The Supervision during construction of Thailand PTA Co-generation, Which was contracted by our country extended into the quality guaranteed period. The supervision during the quality guaranteed period includes the monitor of the operation and maintenance of power plant,organization of subcontractor to treat the problems and defects occurred in the field in time, technical consultancy and communication in time, delivery of spare parts, and assistance of clearing Contractor’s quality deposit. It is proved by the practice that it is necessary to early out the supervision during quality guaranteed period.展开更多
Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling...Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling of the penstock with water represents a critical phase preceding the production of electricity by the first unit.During this interval,the construction of the diversion shaft presents multiple challenges,including intricate construction procedures,considerable construction difficulty,elevated safety risks,and quality control issues.To address this issue,this study uses CFD software to analyze the flow field,pressure gradient,and head loss of shaft curved section with different curvature radius,and examines several key technologies by drawing on the practice of diversion shaft construction at the Meizhou pumped storage power station.These technologies include optimizing the curvature radius of the curved section of diversion shaft,reverse-well excavation for the shaft,and sliding-up for the lining concrete.It is found that as the curvature radius of shaft curved section reduces from 4 to 2 times the shaft diameter,the hydraulic characteristic index does not change much,and the increase of head loss accounts for about 0.18%of the total head loss of the water conveyance system.The result show that optimizing the curvature radius from 4 times to 2 times the shaft diameter is feasible and reasonable,and several improved technical measures have been proposed,such as stabilizing drill rods,mechanical scraper systems,and control technology of the relationship between concrete setting time and formwork sliding.Their implementation effectively mitigates difficulties and safety risks during shaft construction,expedites the project schedule,enhances engineering quality,and creates a 41-month timeline for the principal engineering schedule for the first power unit generation in China.展开更多
On May 23,24,2025,the Annual Conference of Legal Periodicals Association of China Law Society,hosted by the Legal Periodicals Association of China Law Society and organized by Southwest University of Political Science...On May 23,24,2025,the Annual Conference of Legal Periodicals Association of China Law Society,hosted by the Legal Periodicals Association of China Law Society and organized by Southwest University of Political Science and Law and the China Legal Science Journals Press,was held in Chongqing.The theme of the conference is Development of the Rule of Law in China and Construction of Legal Periodicals During the 15th Five-Year Plan Period.Wang Zhenjiang.展开更多
This research focuses on using BIM modeling optimization to control construction-period risks in the pre-construction stage of industrial factory buildings.It analyzes common risk factors and limitations of traditiona...This research focuses on using BIM modeling optimization to control construction-period risks in the pre-construction stage of industrial factory buildings.It analyzes common risk factors and limitations of traditional approaches.BIM-based methods like collision detection,4D simulation,multi-dimensional data integration,etc.,can effectively mitigate risks.Stakeholder collaboration,digital twin testing,and lean BIM integration is also crucial.Case studies show BIM can reduce risks by 32-41%,with a three phase roadmap provided.展开更多
Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the str...Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the structural safety of tunnels in water-rich regions.In this paper,a tunnel seepage model testing system was used to conduct experiments of the grouting circle and primary support with different permeability coefficients.The influences of the supporting structures on the water inflow laws and the distribution of the water pressure in the tunnel were analyzed.With the decrease in the permeability coefficient of the grouting circle or the primary support,the inflow rate of water into the tunnel showed a non-linear decreasing trend.In comparison,the water inflow reduction effect of grouting circle was much better than that of primary support.With the increase of the permeability coefficient of the grouting ring,the water pressure behind the primary lining increases gradually,while the water pressure behind the grouting ring decreases.Thus,the grouting of surrounding rock during the construction of water-rich tunnel can effectively weaken the hydraulic connection,reduce the influence range of seepage,and significantly reduce the decline of groundwater.Meanwhile,the seepage tests at different hydrostatic heads and hydrodynamic heads during tunnel operation period were also conducted.As the hydrostatic head decreased,the water pressure at each characteristic point decreased approximately linearly,and the water inflow rate also had a gradual downward trend.Under the action of hydrodynamic head,the water pressure had an obvious lagging effect,which was not conducive to the stability of the supporting structures,and it could be mitigated by actively regulating the drainage rate.Compared with the hydrostatic head,the hydrodynamic head could change the real-time rate of water inflow to the tunnel and broke the dynamic balance between the water pressure and water inflow rate,thereby affecting the stress state on the supporting structures.展开更多
Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traff...Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS （global positioning system） monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD （empirical mode decomposition） model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.展开更多
In order to solve the problem of low accuracy of construction project duration prediction, this paper proposes a CNN attention BP combination model </span><span style="font-family:"white-space:...In order to solve the problem of low accuracy of construction project duration prediction, this paper proposes a CNN attention BP combination model </span><span style="font-family:"white-space:normal;">project risk prediction model based on attention mechanism, one-dimensional </span><span style="font-family:"white-space:normal;">convolutional neural network (1d-cnn) and BP neural network. Firstly, the literature analysis method is used to select the risk evaluation index value of construction project, and the attention mechanism is used to determine the weight of risk factors on construction period prediction;then, BP neural network is used to predict the project duration, and accuracy, cross entropy loss function and F1 score are selected to comprehensively evaluate the performance of 1d-cnn-attention-bp combined model. The experimental results show that the duration risk prediction accuracy of the risk prediction model proposed in this paper is more than 90%, which can meet the risk prediction of construction projects with high accuracy.展开更多
Based on Lee-Low-Pines(LLP) unitary transformation, this article adopts the variational method of the Pekar type and gets the energy and wave functions of the ground state and the first excited state of strong-couplin...Based on Lee-Low-Pines(LLP) unitary transformation, this article adopts the variational method of the Pekar type and gets the energy and wave functions of the ground state and the first excited state of strong-coupling bipolaron in two-dimensional quantum dot in electric field, thus constructs a bipolaron qubit. The numerical results represent that the time oscillation period T0 of probability density of the two electrons in qubit decreases with the increasing electric field intensity F and dielectric constant ratio of the medium η; the probability density Q of the two electrons in qubit oscillates periodically with the increasing time t; the probability of electron appearing near the center of the quantum dot is larger, while that appearing away from the center of the quantum dot is much smaller.展开更多
With the efficient development of Chinese economic level, the scale of the construction industry has been expanded accordingly. Construction technology has an important impact on construction quality, cost and period ...With the efficient development of Chinese economic level, the scale of the construction industry has been expanded accordingly. Construction technology has an important impact on construction quality, cost and period of construction project, and is restricted by project quality, construction cost and period. Therefore, it is necessary to continuously improve the construction technology, so as to effectively improve the quality of project, reduce the cost of project and control the construction period. This paper will analyze and discuss the relationship between construction technology and project quality, cost, time limit and current situation in detail, and then put forward the effective coordination of four suggestions, in order to provide reference.展开更多
文摘This article focuses on the overall construction duration,explaining the core role of the critical path method and its relationship with the total construction period.It analyzes the factors influencing the total construction duration,introduces the application of BIM and other technologies in identifying and managing critical paths,emphasizes the importance of optimizing resource allocation,and illustrates measures to address disruptions through practical examples.Additionally,it discusses the evaluation system and incentive mechanisms.
基金supported by the National Science and Technology Plan of China (Major Project of the Eleventh Five-Year Plan, Grant No. 2006BAB04A13)the Philosophy and Social Science Fund of Education Department of Jiangsu Province (Grant No. 07SJD630006)+1 种基金the Third Key Discipline (Techno-Economics and Management) of the Project 211the Key Disciplines of Jiangsu Province (Engineering and Project Management)
文摘According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably,
文摘A systematic experimental research work is done for the stability of sunken large diameter cylinder during construction period. It is the first research that gives the method for assessing the stability of the larger diameter cylindrical structure, a set of values is derived also for the critical stability indices of the large diameter cylinder sunken to the sandy seabed.
文摘According to the National Meeting on Power Construction and Cost Control held in Beijing on 26th August 1996, the target for power construction in the period of 9th Five- year Plan is set-up as follows:
文摘The Supervision during construction of Thailand PTA Co-generation, Which was contracted by our country extended into the quality guaranteed period. The supervision during the quality guaranteed period includes the monitor of the operation and maintenance of power plant,organization of subcontractor to treat the problems and defects occurred in the field in time, technical consultancy and communication in time, delivery of spare parts, and assistance of clearing Contractor’s quality deposit. It is proved by the practice that it is necessary to early out the supervision during quality guaranteed period.
文摘Completing the principal engineering components of a pumped storage power station spans between 50 and 60 months,from the inception of construction to the commencement of power generation by the first unit.The filling of the penstock with water represents a critical phase preceding the production of electricity by the first unit.During this interval,the construction of the diversion shaft presents multiple challenges,including intricate construction procedures,considerable construction difficulty,elevated safety risks,and quality control issues.To address this issue,this study uses CFD software to analyze the flow field,pressure gradient,and head loss of shaft curved section with different curvature radius,and examines several key technologies by drawing on the practice of diversion shaft construction at the Meizhou pumped storage power station.These technologies include optimizing the curvature radius of the curved section of diversion shaft,reverse-well excavation for the shaft,and sliding-up for the lining concrete.It is found that as the curvature radius of shaft curved section reduces from 4 to 2 times the shaft diameter,the hydraulic characteristic index does not change much,and the increase of head loss accounts for about 0.18%of the total head loss of the water conveyance system.The result show that optimizing the curvature radius from 4 times to 2 times the shaft diameter is feasible and reasonable,and several improved technical measures have been proposed,such as stabilizing drill rods,mechanical scraper systems,and control technology of the relationship between concrete setting time and formwork sliding.Their implementation effectively mitigates difficulties and safety risks during shaft construction,expedites the project schedule,enhances engineering quality,and creates a 41-month timeline for the principal engineering schedule for the first power unit generation in China.
文摘On May 23,24,2025,the Annual Conference of Legal Periodicals Association of China Law Society,hosted by the Legal Periodicals Association of China Law Society and organized by Southwest University of Political Science and Law and the China Legal Science Journals Press,was held in Chongqing.The theme of the conference is Development of the Rule of Law in China and Construction of Legal Periodicals During the 15th Five-Year Plan Period.Wang Zhenjiang.
文摘This research focuses on using BIM modeling optimization to control construction-period risks in the pre-construction stage of industrial factory buildings.It analyzes common risk factors and limitations of traditional approaches.BIM-based methods like collision detection,4D simulation,multi-dimensional data integration,etc.,can effectively mitigate risks.Stakeholder collaboration,digital twin testing,and lean BIM integration is also crucial.Case studies show BIM can reduce risks by 32-41%,with a three phase roadmap provided.
基金supported by the Chongqing Natural Science Foundation(No.cstc2020jcyjmsxm X0904)the Chongqing Talent Plan(No.CQYC2020058263)+3 种基金the Chongqing Technology Innovation and Application Development Project(No.cstc2021ycjh-bgzxm0246)the China Postdoctoral Science Foundation(No.2021M693739)the Sichuan Science and Technology Program(No.2021YJ0539)the Natural Science foundation of Jiangsu higher education institutions of China(Grant No.19KJD170001)。
文摘Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the structural safety of tunnels in water-rich regions.In this paper,a tunnel seepage model testing system was used to conduct experiments of the grouting circle and primary support with different permeability coefficients.The influences of the supporting structures on the water inflow laws and the distribution of the water pressure in the tunnel were analyzed.With the decrease in the permeability coefficient of the grouting circle or the primary support,the inflow rate of water into the tunnel showed a non-linear decreasing trend.In comparison,the water inflow reduction effect of grouting circle was much better than that of primary support.With the increase of the permeability coefficient of the grouting ring,the water pressure behind the primary lining increases gradually,while the water pressure behind the grouting ring decreases.Thus,the grouting of surrounding rock during the construction of water-rich tunnel can effectively weaken the hydraulic connection,reduce the influence range of seepage,and significantly reduce the decline of groundwater.Meanwhile,the seepage tests at different hydrostatic heads and hydrodynamic heads during tunnel operation period were also conducted.As the hydrostatic head decreased,the water pressure at each characteristic point decreased approximately linearly,and the water inflow rate also had a gradual downward trend.Under the action of hydrodynamic head,the water pressure had an obvious lagging effect,which was not conducive to the stability of the supporting structures,and it could be mitigated by actively regulating the drainage rate.Compared with the hydrostatic head,the hydrodynamic head could change the real-time rate of water inflow to the tunnel and broke the dynamic balance between the water pressure and water inflow rate,thereby affecting the stress state on the supporting structures.
文摘Construction progress of long-span bridge is complicated and the quality control is strict. Any disadvantage during construction may potentially affect the internal forces and deck alignments after it is open to traffic. To exactly evaluate the periodic alignments, internal forces and safety, geometrical and physical monitoring are needed during construction. This study aims at the requirement of dynamic geometric monitoring during Sutong Bridge construction, and introduces the realization and observing schemes of the self-developed GPS real-time dynamic geometrical deformation monitoring system. Affected by wind load and construction circumstance, GPS （global positioning system） monitoring signal contains a variety of noise. And the useful signal can be extracted from the signal after de-noising the noises. A de-noising method based on EMD （empirical mode decomposition） model is introduced here to process the bridge dynamic monitoring data, and with the wavelet threshold de-noising method are compared. The result shows that the EMD method has good adaptability, is free from the choice of wavelet bases and the number of decomposition layer. The method is an effective de-noising method for dynamic deformation monitoring to large-span bridges.
文摘In order to solve the problem of low accuracy of construction project duration prediction, this paper proposes a CNN attention BP combination model </span><span style="font-family:"white-space:normal;">project risk prediction model based on attention mechanism, one-dimensional </span><span style="font-family:"white-space:normal;">convolutional neural network (1d-cnn) and BP neural network. Firstly, the literature analysis method is used to select the risk evaluation index value of construction project, and the attention mechanism is used to determine the weight of risk factors on construction period prediction;then, BP neural network is used to predict the project duration, and accuracy, cross entropy loss function and F1 score are selected to comprehensively evaluate the performance of 1d-cnn-attention-bp combined model. The experimental results show that the duration risk prediction accuracy of the risk prediction model proposed in this paper is more than 90%, which can meet the risk prediction of construction projects with high accuracy.
基金supported by the Natural Science Foundation of Hebei Province(No.E2013407119)the Items of Institution of Higher Education Scientific Research of Hebei Province(Nos.ZD20131008 and Z2015149)
文摘Based on Lee-Low-Pines(LLP) unitary transformation, this article adopts the variational method of the Pekar type and gets the energy and wave functions of the ground state and the first excited state of strong-coupling bipolaron in two-dimensional quantum dot in electric field, thus constructs a bipolaron qubit. The numerical results represent that the time oscillation period T0 of probability density of the two electrons in qubit decreases with the increasing electric field intensity F and dielectric constant ratio of the medium η; the probability density Q of the two electrons in qubit oscillates periodically with the increasing time t; the probability of electron appearing near the center of the quantum dot is larger, while that appearing away from the center of the quantum dot is much smaller.
文摘With the efficient development of Chinese economic level, the scale of the construction industry has been expanded accordingly. Construction technology has an important impact on construction quality, cost and period of construction project, and is restricted by project quality, construction cost and period. Therefore, it is necessary to continuously improve the construction technology, so as to effectively improve the quality of project, reduce the cost of project and control the construction period. This paper will analyze and discuss the relationship between construction technology and project quality, cost, time limit and current situation in detail, and then put forward the effective coordination of four suggestions, in order to provide reference.
