Abstract:Hong Kong-Zhuhai-Macau Bridge project is the deepest buried depth of immersed tunnel in the open sea.The tubes in this project have large cross sections,heavy weight,and high standard of crack resistance of concrete.It is the first one using industrial prefabricated immersed tubes for tunnel construction in China.Due to complexities of the prefabrication technology,deep studies were made to develop various improvements and innovations.This paper mainly outlines the industrial prefabrication technology and its application.

Abstract:Based on the analysis of natural conditions and boundaries,numerical model of wave field of each construction phase was set up using MIKE21 wave stimulation model on the background of Ashdod port project.The wave propagation within the harbor was obtained by numerical analysis under different construction stages along with the results of the maximum working wave heights and unavailable working days.Reasonable schedule of construction was made and working window was selected according to the results.Moreover,this paper provides a scientific and reasonable construction procedure for the Ashdod port project.

Abstract:The stiffness of jack-up construction platform structure is weak,by offshore large waves and long period of time of swell,the structure produces a violent dynamic response.Based on the linearized equation of Morrison and random wave theory and using ANSYS finite element software,we carry out the modal analysis and transient dynamic response analysis,by which we obtain the frequency characteristics and vibration characteristics.The result provides a theoretical basis for the safety and reliability of evaluation platform,as well as control of the vibration response of the platform structure.

Abstract:Based on the principle of displacement compatibility,force balance and energy conservation,considering the discount coefficient of the lateral soil resistance on piles in the NL method,and fitting curves between the deformation and stress of the rubber fender,we analyze the energy allocation of steel-pile cluster and rubber fender.The result was applied to the design of the clustered fender piles in the jetty project of Moulmein and achieved a good effect.

Abstract:The current domestic large temporary works mainly adopt steel structures for the recycled use.As the load on the large temporary works become heavier,the steel structures would cost more.Therefore,it is a challenge to ensure the safety of the structure and reduce steel consumption as far as possible.This article describes the design of the girder upgrading gantry for a temporary dock project of HZMB.Adopting different structure forms and making full use of the existing materials,we finally determine the reasonable structure of the gantry.

Abstract:The geologic condition of the Hadarom port project to be built is unfavorable,and the site is dominantly covered by rocks of 0～3 t.The adverse wave condition has a maximum significant wave height of above 5 m,which causes a great deal of troubles for the offshore construction.The innovative quay design adopts the combination of non-anchor sheet pile and supporting pier based on comprehensive comparisons with traditional high-pile wharf,riprap embankment wharf and sheet pile quay,etc.With safe and reliable construction technique,the construction is completed safely with high efficiency .

Abstract:A new-type precast reinforced concrete retaining panel wall with anchor block is proposed by setting anchor blocks at the end of the reinforcement.Based on the Euro code and American standard,we give the safety checking method under the extreme event limit state of vehicular impact.Also,by comparing domestic codes and foreign codes,we point out the differences between them.The practical application shows that this new-type precast reinforced concrete retaining panel wall with anchor blocks is better in structure and more economical in the use of materials.This new-type retaining wall has a broad application prospect.

Abstract:The sand pillow bag can effectively prevent the flow to scour the bottom of the riverbed,and thus is the main reinforcement measures for stabling the riverbed and bank slope and preventing erosion.Based on the construction of Jingjiang waterway regulation,we introduce the construction technological process and main points of sand pillow bottom protection,and emphasize the control measures and effect of the sand pillow bags under the influence of the Yangtze River water flow.

Abstract:A new kind water-proofing additive can fundamentally prevent water absorption through the capillary pore and keep chlorine ion out of the concrete structure,so as to prevent reinforcement corrosion.This paper studies the performance of the new-kind water-proofing additive,including the influence on both mortar and concrete;Takes the lead to use the British Standard to evaluate the water absorption rate of concrete;Furthermore,it compares it with the same-kind similar foreign products.The new-kind water-proofing additive can improve 7 d and 28 d compressive strength and the anti-permeability of both mortar and concrete in case of no changing the working performance.

Abstract:This paper researches the preparation technology of C50 box girder concrete with mechanism sand and natural river sand,according to the engineering design requirements of C50 box girder concrete of Guangxi Wuliu highway engineering,and combining with the corrosion characteristics of the local environment.Comparing and analyzing the mechanical properties,crack resistance,durability performance and volume stability of the two kinds of concretes,we draw the conclusion that the working performance of C50 sandstone-mechanism sand box girders concrete is similar to that of the concrete with natural river sand;the physical performance of the former such as compressive strength,axial compressive strength and elastic modulus are better than that of river sand concrete.Selecting appropriate dosage of the gelled material and the admixture,we can proportion the C50 sandstone-mechanism sand box girder concrete which has better durability performance and volume stability than the river sand concrete.

Abstract:The paper investigates the effectiveness of wave dissipation of a new type of breakwater which is a floating structure with vegetation planted.Under the premise that the height of the vegetation is higher than the wave,the factors influencing the effectiveness of wave dissipation of the floating wave dissipater in unidirectional regular wave environments are analyzed.Based on comprehensive experimental flume data,the effectiveness of wave dissipation of the floating wave dissipater with vegetation planted under regular wave are correlated with the plant density,relative width of the structure and wave steepness.The experiment results show that the plant density and the relative width of the structure are the most important factors affecting the wave dissipation,and this floating wave dissipater with vegetation planted plays a significant role in wave dissipation.

Abstract:Combining with the underwater unscattered concrete preparation test in Wuchuan Shuangliu slide base engineering,we introduce the selection of raw materials,design of mix proportion,as well as the method,process and results of the grouting test for C40 underwater unscattered concrete,to provide reference for similar projects.

Abstract:This research conducts an indoor experiment simulation of acid rain and a comparative research on the influence of mineral additives,the curing time,and surface protection methods on the concrete mass loss,the compressive strength loss,and the neutralization performance.The results show that after adding mineral additives,the concrete specimen mass and the compressive strength loss reduce more than premixing concrete with only cement to a certain degree,and a better inhibitory effect can be achieved when fly ash and slag are added in appropriate proportion.It also indicates that the concrete specimen mass loss and the compressive strength loss can be reduced with the extension of standard curing time.The concrete specimen mass loss,the compressive strength loss,and the neutralization performance can be prevented when silicaneor coating is applied to its surface,and the effect of coating is better.

Abstract:According to the actual construction process of air cooling system of the Fuchun river lock expansion and improving project,through the real-time monitoring of coarse aggregate,mixing water,the concrete mixer outlet temperature and pouring temperature,this article gives a comprehensive study on the cooling capacity of the air-cooling aggregate and its cooling water system,to provide guidance for the later construction.

Abstract:In the dam flood discharge area,the lock cofferdam construction faces problems of large flood discharge flow and large height of water,which demands high technical performances,such as anti-scouring stability,anti-leakage of cofferdam,etc.Therefore,it is necessary to grasp the key points of design and construction of the cofferdam.This paper focuses on the successful experience of the design and construction of the cofferdam of Fuchun river lock expansion project.

Abstract:This article describes the installation method of berthing members under the condition of high water level when the conventional method can’t be implemented.Analyzing the construction process and final results,we know that the method presented here ensures the smooth installation construction of the berthing members and girders as well,so as to lay a foundation for the continuous construction of the whole project.

Abstract:Based on a high-piled wharf upgrading project,we expound the piling technology,i.e.piling between bents of the original wharf after demolishing the original wharf,and the new piling technology which combines the vibration hammer with the diesel hammer in the area seriously influenced by the neighboring structures and with complicated geologic conditions,to serve as reference for the piling construction of similar projects.

Abstract:During construction of the permanent offshore platform in Jiangsu offshore observation platform project, to counter the extremely harsh weather condition,we carry out an optimization of the conventional construction scheme for the abutment and the observation house,and adopt the construction technology of integral prefabricating on land and installing at sea,by which the construction period of the main part of the project is greatly shortened .The optimized construction technology may serve as reference for similar projects concerning the offshore platform engineering.

Abstract:Starting of the tunnel boring machine (TMB) is one of the key points which directly affect the effect of tunnel construction.The TBM started in the soft soil layers faces more difficulties and risks than those started other soil layers.Freezing on the starting end of TMB for consolidation is used during the construction of work-Nanjing Weisan road tunnel N crossing the Yangtze River and acquires a good effect.This text elaborates the design of freezing on the starting ends for consolidation,key construction points of such freezing technology and its construction effects.

Abstract:The lock’s foundation pit is usually excavated in dry condition formed by dewatering.Based on the analysis of the special foundation Yunyan river lock which consists of soft soil and silty soil,and combining with the actual excavation,we research a new method to avoid the traditional dewatering method.According to the research on the local trial-excavation technology for the chamber soil,we sum up a new construction technology that can directly excavate the chamber’s deep foundation pit,set the inverted filter locally and utilize water channel in the permeable area.

Abstract:Plugging often happens during construction of bored piles,which affects the engineering quality or leads to pile’s scrapping.To reduce this risk,we carry out a theoretical analysis on the plugging reasons and take multiple measures such as due vibro-flotation in practice.Moreover,we develop the vibration hammer impacting method and re-insert catheter.The engineering effect is remarkable,and it may serve as reference for other projects.

Abstract:The bridge section of 6 m×9 m on north secondary navigable span of Wuhan Erqi Yangtze River Bridge is located on the third terrace of the Yangtze River.As high variability in hydrogeological condition during construction period,the proposed construction method for the bridge foundation using steel boxed cofferdam is affected seriously.Based on the analysis of the form characteristics and applicability of common types of cofferdam in the shoal area and combining with the actual condition of the project,we adjust the construction method for the bridge foundation to steel sheet pile cofferdam to improve the construction efficiency and save the cost.

Abstract:Based on the analysis of the engineering characteristics and construction conditions of the crest wall for the deepwater sheet-pile wharf in Pakistan,we adopt the skipping hanging frame to provide a support platform for the formwork and take quality control measures to solve the construction difficulties and form a serious of reliable and feasible construction technology.

Abstract:In combination with the practical situation of engineering,in order to reduce the engineering cost,we adopt site splicing of the steel pipe piles and inflatable capsule plug float hauling method during the construction of piles.Based on the analysis of the feasibility of steel pile floating,we introduce the plug fabrication and installation and the mode of float hauling method,and analyze its advantages.This method achieves a satisfactory effect during construction.

Abstract:Taking the crest rail beam installation in the navigation-power junction discharge sluice in Xiangjiang river for example,we analyze the installation environment and possible installation mode of the crest beam,and establish a comprehensive installation mode,i.e.homemade hydraulic lifting equipment and erection of beam transportation channel successful,by which we fulfill the installation of the single track beam smoothly.

Abstract:Based on the technical requirements of soft foundation which needs foundation treatment used on the stone column in the supporting project,we analyze the project features and weather windows.Studying different construction methods and equipment for the stone column,and combining with the ergonomics analysis,we put forward a new type of construction platform for the stone column using the jack-up platform as the carrier.

Abstract:The lateral bending of T beam increases the deflection of gravity center,which not only leads to the difficulty of the beam’storage,but also brings a series of problems for the lifting of the beam.Meanwhile,the lateral bending also affects the progress of bridge construction.If the bending is too large,it will cause adverse force to the beam,which is easy to lead to a serious accident.This paper analyzes the lateral bending of precast post-tensioned T beam,proposes corresponding control measures to guide the construction and control effectively the construction quality,hoping to serve as reference for persons of the same occupation.

Abstract:Using auxiliary piles as the foundation platform to set up the platform,the problem concerning the construction platform for the rock-embedded cast-in-situ piles in the bare rock of the Yangtze River steep slope is solved;Employing planting piles in the rock surface slope,box type guide frame and steel playing up technology,the sinking operation of the super long and large-diameter steel tube under the condition of bare rock and torrents of the Yangtze River is implemented.

Abstract:In the construction of steel sheet pile cofferdam,there often exists problems of low accuracy,leakage from the joints,etc.So,we carry out corresponding research and take measures including single pile splicing,setting of the guide frame,installation of a double platform,adopting of special shaped piles,etc.,and achieve satisfactory construction effect.

Abstract:Fuchunjiang river lock expansion and improving project is featured with a large quantity of concrete pouring,complex structure and high requirements on the durability,and the concrete cracks are required to be controlled strictly.For the concrete mix proportion design,we select the best aggregate gradation based on the aggregate gradation optimization test,use a large amount of mineral admixtures by mixing concrete with slag and fly ash to reduce the dosage of cement and control the rise of concrete heat of hydration temperature;By tests,we choose the optimal sand ratio to improve the volume stability of concrete and reduce shrinkage,and improve the crack resistance of concrete.

Abstract:The large overhanging beam is not commonly used in the high pile wharf,because the beam is overhanging,the supporting system of the bottom formwork faces more difficulties than the conventional beam in construction.This paper mainly introduces the construction technology of the bottom formwork of large overhanging beam on water and the bottom formwork support design in the dock project,and describes the design and application of the steel hoop as bearing support structure in the bottom beam construction.

Abstract:The anchorage fastening system is a lifeline engineering to a suspension bridge,for its design and construction quality may decide the safety and durability of the bridge to a great extent.In order to improve the structure’s reliability and durability,the tunnel anchorage fastening system of Guanshan bridge is designed as an innovative formed steel fastening system,which requires a high accuracy in location.This paper describes the key technology of the anchor beam and anchor rod installed and constructed in the cramped and tilted tunnel anchorage cave.

Abstract:Based on Ras Al Khair sea port berths No.5 & 6 project,we introduce the measures of mass concrete cracks control under the conditions of hot and dry extreme temperatures and marine environment for the breast wall designed and constructed according to the American standard.In the process of construction,by selecting the mixing ratio,materials’temperature control,pouring temperature control,hierarchical and segmental construction,maintenance and other comprehensive measures,we control effectively the crack of lmass concrete of the breast wall,and ensure the construction quality and progress.

Abstract:As the high concrete strength,large size andsevere service environment for super-large section tunnel which includes the precast immersed tube and the cast-in-suit tunnel in the artificial island of Hong Kong-Zhuhai-Macao bridge,crack control of concrete is difficult.Harmful cracks can be controlled effectively by a series of treatment measures during the construction period such as precasting in the factory,one-piece casting,controlling concrete raw material temperature,mixing concrete with ice shavings and cooling water,setting up automatic curing system for the precast immersed tube and reasonable layered and segmented,water pipe cooling,compensating contraction concrete for the cast-in-situ tunnel.Moreover,the harmful crack does not appear in both the precast immersed tube and the cast-in-situ tunnel appear and the prospective objective of temperature control is achieved.

Abstract:The beam & girder and track installation works of Wuchuan slipway project is just on the main stream side of the Yangtze River where the water is deep and swift.According to the characteristics mentioned above,and due to the difficulties of high accuracy requirement of underwater track installation as well as the tight time limit,we combine the construction and measurement in the process of grillage beam prefabrication,assembly and installation,to provide reference for similar comb type slipway engineering.

Abstract:The hydraulic grab head and impact drill are the main equipment for large underground continuous wall construction,but in overseas engineering,because of the lack of local construction equipment and other constraints,it is difficult to meet the needs.With limited equipment resources,i.e.only two rotary drills,one impact drill and mud purification machine,we explore the new technology of underground continuous wall construction considering the local existing resource and by the technological innovation,to meet the needs of the underground continuous wall construction in the pure seawater environment.

Abstract:This paper describes the application of vacuum-surcharge combining preloading method in Saigon,Vietnam international container terminal,and analyzes the site monitoring data and test results.The results show that the application of this technology is feasible,and the consolidation effect on the soft ground is well and the method is worthy of spreading.

Abstract:The treatment technology of shallow sand free cushion by vacuum preloading is improved based on the traditional vacuum preloading process,and becomes the common way of treatment for the soft soil foundation in recent years.Combining with the real case of soft soil foundation treatment by vacuum preloading,we expound the characteristics and implementation effect of the vacuum preloading technology,to serve as reference for the similar engineering.

Abstract:The bamboo net and geotextile technology takes the bamboo as the main construction material to deal with the surface of soft ground.Binding the bamboo net with geotextiles and other geosynthetics to form a reinforced semi-steel body,the upper surface of which is covered with the sand layer or soil cushion with a certain thickness to enhance the bearing capacity of the soft ground base and meet the requirements of the operation surface for the light & medium sized equipment construction.In the WE3 road surface soft foundation treatment of the eastern part of the economic zone and municipal infrastructure construction projects of Shantou city,according to the thickness of the silt layer,we adopt the bamboo net treatment technology,and quicken the construction progress and save the construction cost.

Abstract:Based on the construction of rock-embedded raked pile for Hubei Yadong special wharf,this text summarizes the technical difficulties of rock-embedded raked pile constructed by the common hydraulic swing drill,and puts forward the treatment measures for the difficulties.