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In order to complete the construction of the Shenzhen-Zhongshan Link subsea tunnels with higher efficiency and quality, the high -precision and rapid docking of subsea tunnels has become a major challenge. Taking into account the characteristics of the ultra-wide steel-shell immersed tube tunnels, a high-precision and rapid docking technology for the Shenzhen-Zhongshan Link tunnels, and a set of positioning control systems for the head and tail locations of the immersed tubes was proposed, which includes multi -system linkage technologies such as mooring system, Beidou positioning and measurement control technology, and integrated barge control system. Through practical application, the maximum absoluted eviation of the central axis and the maximum lateral relative deviation of the immersed tube tunnel of the Shenzhen-Zhongshan Link were both controlled within the design deviation of 依5 cm. The results indicates that the integrated barge for transportation and installation has significant advantages during the high-precision docking process, which provides strong support for the construction of immersed tube tunnels in China. [ABSTRACT FROM AUTHOR]

In order to overcome the influence of shallow seas, low headroom and existing bridge structure on the construction of jet grouting piles, the construction technology of mobile working platform + jet grouting with connecting rods at sea was studied and put into practical application, based on the contraction practice of the East Artificial Island of Shenzhen-Zhongshan Link. Engineering practice shows that: 1) the construction technology of mobile working platform + jet grouting with connecting rods effectively solves the technical problems in jet grouting pile construction at sea and the working platform has a wider applicable range; 2) the dynamic speed control system based on theoretical calculation formulae can better ensure the quality of jet grouting pile construction, and the deviation rate of cement dosage is only 2.4% ; 3) the impact of the construction process on the existing bridge structure is mainly manifested in horizontal displacement in the down-bridge direction and the deformation value fluctuates in the range of -1.3 ~1.7 mm, which meets the high requirements for deformation control of extremely sensitive buildings (structures). [ABSTRACT FROM AUTHOR]

The complex conditions and harsh construction environment at the site of the secondary navigable span of Xiushan Sea-crossing Bridge, such as strong winds, great water depth, rapid currents, and large tidal range, brought great difficulties to the selection of cofferdams for pile caps, installation control of the cofferdams, pile cap construction and removal of suspension box cofferdam. In order to solve the technical problems in the construction of pile cap cofferdams and ensure the quality and safety of pile cap construction, an appropriate cofferdam structure was determined through hydrological survey, research and analysis. During the construction, the overall structure and detailed components of the steel box cofferdam were improved and designed innovatively. The steel box cofferdam was fabricated as an integral structure and lifted and transported as a whole, which was installed with technology of precise positioning and rapid installation to realize the rapid installation, disassembly and turnover of the steel box cofferdam, thus solving the technical problem that the lowering accuracy of the cofferdam is difficult to control due to current force and wave force. [ABSTRACT FROM AUTHOR]

In view of the difficulties in the construction of the giant deep-buried cap near the river of the long-span bridge, the traditional construction technology leads to the large steel consumption of the supporting structure, and the unreasonable structure stress, the construction technology of dry soil extraction is put forward. Relying on the design and construction of the supporting structure in the No.Z5 pier cap of Maanshan Rail -highway Bridge and comparing the traditional underwater soil extraction with the new dry soil extraction technology, the green construction scheme of dry soil extraction with steel structure system as support structure and auxiliary precipitation is finally selected because of the lower material usage and shorter construction time. Provided more energy saving and environmental protection ideas and direction to solve this kind of foundation pit supporting problems. [ABSTRACT FROM AUTHOR]

In terms of the deep sandy site of the Coco d'Ivoire Bridge project, in order to determine the bearing characteristics of the bored piles under rotary auger construction and rotary drill construction techniques, four bored piles with a diameter of1.6 m and 2.0 m were selected on site for static load test. The field test results show that the pile bearing capacity constructed by the rotary drill is about 31.6% of that constructed by the rotary auger construction, where the shaft resistance is reduced significantly. In addition, the bored pile with longer pile length is prone to thick sediment at the base of the pile due to its longer hole-forming time. As a result, the settlement during the first cyclic loading is significantly greater than that during the second cyclic loading. Therefore, in the deep and thick sandy soil layer of this project, the construction technology of rotary auger is better than that of rotary drill, and shortening the hole-forming time would be helpful for ensuring the pile bearing capacity. [ABSTRACT FROM AUTHOR]

Guanshan to Xiushan channel is a typical deep water and strait -channel sea area, with uneven and W -shaped underwater terrain, exposed bedrock, steep rock face and high rock strength. Xiushan Bridge crosses the strait -channel sea area, with the maximum dip angle of the rock surface at the pier position is 30毅, the maximum water depth is 39 m and the maximum flow rate is 3.8 m/s. It is extremely difficult to construct the drilling platform of the pile foundation construction in deep water. By comparison of different methods for piles foundation construction, the structural strength, and anti-overturning and anti-slip performance of the jack-up platform were analyzed, and the construction technology of building pile foundation drilling platform by jack -up platform was proposed, which has effectively solved the problems of pile foundation drilling platform construction in the sea area with exposed bedrock, high strength, steep slope, deep water, high velocity of flow, and significant strait-channel effects. It can provide a reference for similar engineering construction. [ABSTRACT FROM AUTHOR]

The offshore construction environment is harsh, and the single pile stabilization technology is the key technology to control the verticality of offshore wind power single piles. Aiming at the jack-up stable pile platform developed in this paper, the construction technology of single pile sinking pile was studied and applied to Guohua Dongtai Offshore Wind Power Project. The application results show that the construction quality of the single pile construction technology of the jack-up stable pile platform meets the design and specification requirements, and the construction efficiency is higher, the number of ship machines is less, and the economy is better. [ABSTRACT FROM AUTHOR]

Haoji Railway (the former Menghua railway) is located in the hinterland of the Maowusu Desert, with abundant aeolian sand resources. If aeolian sand is used as subgrade filling, a lot of money will be saved. Therefore, in this paper, the construction technology of aeolian sand filling, such as different paving thickness, different mechanical combination and compaction times was studied by using wet filling. The results show that it is feasible to use aeolian sand as roadbed filling material to spray water and compact under the natural moisture content; the moisture content control range is 6.3%-11.3%; the reasonable layer thickness of wet construction is 30 cm, and the corresponding loose paving coefficient range is 1.1-1.14. Reasonable mechanical combination and compaction times were put forward. This achievement has been implemented in Haoji Railway, which speeds up the construction progress and saves a lot of manpower and material resources. [ABSTRACT FROM AUTHOR]

Airport runway project is the core part of the airport flight area, the quality of the construction process control has a great influence on its service life. It must be ensured that the airport runway does not appear the phenomenon of broken plate, edge off, poor flatness, and meets the requirements of durability and surface wear resistance. In this paper, through summarizing the construction experience of cement concrete airport runway project for many years, we introduced control points and testing standards of the construction process in detail from the aspects of materials, equipment, process, etc. On the basis of meeting the quality requirements, we put forward the construction technology innovation achievements and subsequent development plan of cement concrete airport runway surface, the results have certain reference significance for other similar projects. [ABSTRACT FROM AUTHOR]

With the construction of more and more cross-sea bridges, the construction environment of the superstructure is becoming more and more complicated. Based on the construction of the movable formwork of the Hainan Puqian Bridge, we studied the difficulties in the construction of moving formwork for curved cast-in-situ box girder with high pier and variable beam height in violent typhoon sea area, such as the frame wind resistance, small radius curve section over span, prefabricated steel bar installation, high pier bracket installation, variable beam height box girder moving formwork construction, and offshore demolition. Through the optimization of the structural form of the movable formwork and the innovation of the construction process, the series of technical problems in the construction of the cast-in-situ box girder with high pier and high variable beam height are solved. [ABSTRACT FROM AUTHOR]

Arranging tower crane foundation inside basement floor, it makes sure of its applicability and economy, as well as its function of structural design of floor. Based on an engineering example, through the characteristic analysis of different types, program selection, and the control of key details, the application of construction technology for combining temporary tower crane foundation with permanent basement floor was studied. The technology achieves integration benefits from the process management of construction and design, reduces building difficulty, and ensures the joint quality of basement floor and tower crane foundation. It can provide some ideas and references for similar engineering. [ABSTRACT FROM AUTHOR]

The final joint of the Hongkong—Zhuhai—Macao Bridge immersed tunnel is located between the S8 section of the E29 immersed lube and the SI section of the E30 immersed tube, about 580 m from the head of the East Island, the lowest elevation of the lube bottom is -27.937 m. and the steel shell concrete structure is located in the curve section with a radius of 5 500 m. Its underwater closure welding construction is the most risky subproject in the entire project construction. In order to minimize construction risks and continuously optimize the construction technology, a set of mature and reliable underwater-welding construction plan was found through pre-construction simulation exercises. In the end, the underwater welding task was completed with a one-time welding pass rale of 97.8%, which has made a major contribution to the smooth completion of the Hongkong—Zhuhai-Macao Bridge and created many of the best in the world. [ABSTRACT FROM AUTHOR]

The construction of riprap lamping for the immersed tunnel foundation is a basic project of the Hongkong— Zhuhai— Macao Bridge. It is necessary to fill 10 — 100 kg block stones in the deep base trough of the submarine tunnel, increase the compactness of the base bed through underwater tamping, and improve the bearing capacity of the immersed tube foundation, and then lay the gravel cushion and install the immersed tube sinking and docking. The project has the characteristics of a particularly large project volume, a particularly long construction area, a particularly complex navigation in the construction sea area, a very difficult construction, very high accuracy and environmental protection requirements, and a particularly light construction period. This paper introduces the development and successful application of the construction technology of the riprap tamping equipment in detail, which can provide reference for similar foundation treatment projects of offshore, deep water, large runoff and deep foundation trough. [ABSTRACT FROM AUTHOR]

Aiming at the deep three—axis cement mixing pile short pile, the problems such as pile-forming difficulty, low strength, uneven and insufficient elevation of pile bottom are olten encountered in the construction of viscous soil layer, in order to control the quality of pile, reduce the amount of cement, optimize the construction technology and solve the problems existing in die construction process, by adjusting the construction technology and changing the cement content, a large number of field validation tests have been carried out. The field lest results show that the cement loss amount should lie fully considered in the construction of short pile, and the unconfined compressive strength of piles can meet engineering requirements by properly increasing the cement content; the construction process of this project was determined as follows: lour-spray four-stirring, sinking speed 1 m/min, lifting speed 0.5 m/min, static spray 60 s at the height of pile bottom, water-cement ratio of 1.0; in order to meet die elevation of the pile bottom, the ultradepth footage must be not less than 0.5 m. The research results can provide references for similar projects. [ABSTRACT FROM AUTHOR]

The closure gap gate in deepwater dike with large tidal range is wide and will be a large work quantity with high risk. Taking a large-scale deepwater dike of Hangzhou Bay as an example, by optimizing the bottom protection structure, we adopted double-layer soil mattress and long sand bag bottom protection to form a closure gap protection. In order to reduce the risk of closure, we chosen a construction technology by riprap and determine a proper elevation of the riprap dike priorlv, and then implement the prism earth closure. A number of riprap ships were engaged in the closure in batches 1mm high tide to low tide, and closure dam was built meanwhile, during the closure of prism earth, efficient large—scale ship machines and equipment were applied in proper time every day lor bagged sand closure and vertical blocking of gas, so that the closure was completed successfully. [ABSTRACT FROM AUTHOR]

Vacuum measuring device is very important for operation condition monitoring of mud pump and construction technology control of hydraulic dredger. There are two different types of relative pressure gauge and relative difference-pressure gauge. The physical significance and application scope on indication number of the two kinds of vacuum gauge are different, which need to be different in dredging operation and process analysis. We compared the principles and characteristics of different types of vacuum measuring devices, introduced the application of common vacuum measuring devices of dredgers in China and the construction technology control measures of different types of vacuum measuring devices. The influence degree of production caused by misunderstanding of common parts in construction is also analyzed, which can be used as a reference for dredger operators and technicians. [ABSTRACT FROM AUTHOR]

Through the application of hydraulic climbing formwork construction technology in the main tower of CCCC Hengqin Huitong Financial World project, we introduced the structure, installation, construction technology and key points of the hydraulic climbing formwork system. According to the structural changes and the related parts of the tower crane, we discussed the construction technical measures of hydraulic climbing formwork, and expounded the corresponding solving methods of climbing formwork system, which effectively solves the specific problems in the process of climbing formwork construction. [ABSTRACT FROM AUTHOR]

To choose mechanical equipment and construction technology reasonably and conomically according to the characteristics and conditions of the project is the fundamental factor in selecting the optimal construction scheme. We analyzed the major factors having effect on several key construction technologies and key mechanical equipments such as mass concrete construction of basement floor, climbing formwork system, vertical transportation system and etc. According to actual situation of the project, appropriate technology used in the project is determined. [ABSTRACT FROM AUTHOR]

Combining with the construction of fair-faced concrete pump house in the east artificial island of Hongkong- Zhuhai-Macao Bridge island and tunnel project, the fine construction technology of thin-walled structure of fair-faced concrete is introduced. We elaborated the construction technology of fair-faced concrete and formwork in pump house, and put forward corresponding construction scheme and technological improvement measures for wall thin-walled structure, which can provide reference for relevant professionals or similar engineering projects. [ABSTRACT FROM AUTHOR]

The design diameter of the pile foundation under the No.34 main pier of Puqian Bridge in Hainan Province is 4 m and the design pile length under the left and right caps is 40 m and 31 m respectively. It is difficult to make, transport and install the pile foundation with four layers of reinforcing steel cage in the radial direction because of many layers and selfweight. In view of this problem, we put forward the construction technology of installation, fabrication, connection, splitting, transportation, lowering and installation of steel cage, and formulated the quality assurance measures of keeping the reinforcing cage stable, not deforming and accurately lowering during hoisting process. When the acoustic tube is installed, the joint or leaking portion shall be reinforced and sealed in time. The application of this technology guarantees the construction quality and greatly saves the cost. It has a good engineering significance and application value for the construction of reinforcing steel cage of super-large diameter pile foundation. [ABSTRACT FROM AUTHOR]

High pressure rotary jet grouting pile is widely used in seepage control and foundation reinforcement because of its fast construction speed and low cost. However, the construction technology and parameters of high-pressure rotary jet grouting pile under different geological conditions vary greatly in the codes. Engineering practice shows that the construction quality of high-pressure rotary jet grouting pile in sand-gravel layer is not easy to control. Taking the construction of high-pressure rotary jet grouting pile in a waterway hub project as an example, we pointed out the quality problems and causes of the construction of high-pressure rotary jet grouting pile through systematic analysis of geological conditions, construction technology and test results in the construction process, and put forward corresponding improvement measures. The construction quality of highpressure rotary jet grouting pile in sand-gravel layer has been effectively improved by means of equipment improvement, sequential construction, adjustment of lifting rate and increase of cement consumption. [ABSTRACT FROM AUTHOR]

Based on the construction of artificial island steel cylinders for the Hongkong-Zhuhai-Macao Bridge Island & Tunnel Project, 8 high-power hydraulic hammer linkage vibration and sinking systems were used for the first time in the world, and super-diameter and ultra-deep buried steel cylinder vibration and sinking techniques were used for the first time in China. It has successfully implemented the rapid formation of offshore artificial island steel cylinder enclosure structure. It has achieved the goal of "starting construction in the same year and becoming an island in the same year", it provides a safe, reliable and stable dry construction environment for the island, and has many advantages, such as fast, efficient, safe and environment protection. It lays a solid foundation for the smooth development of the Hongkong-Zhuhai-Macao Bridge Island & Tunnel Project, and provides a reference for other similar projects. [ABSTRACT FROM AUTHOR]

The Miaozui Sanjiang Bridge using main-span 210 m central cable plane high and low tower cable-stayed bridge. We introduced the construction solutions of the central cable plane ramp variable cross-section box girder form traveller. With the introduction of hydraulic synchronization technology，we implemented the multi-point synchronous walk of form traveller, and solved the problem of the asymmetric of gravity center. Practice has proved that the form traveller successful completion of the cross section of the tower root ramp box girder casting construction, which greatly improves the construction efficiency and economic benefit. The technical scheme has reference and promotion value. [ABSTRACT FROM AUTHOR]

The light-weakening measures of tunnel entrance directly affect the comfort and safety of the driver, which is a difficult problem in tunnel construction. Through a summary of the design and construction of the light-weakening buildings of the Hongkong-Zhuhai-Macao Bridge, we introduced the functional requirements of the light-weakening building of the bridge, described its construction technology and quality acceptance standard, which can provide references for the design and construction of the light-weakening measures in tunnel entrance in subsequent offshore tunnel. [ABSTRACT FROM AUTHOR]

In case of construction of cofferdam closure in over-sized surrounding area, the closure of single closure gap will cause the excessive workload in closure period, extended closure period and adverse effect on closure due to large storage capacity, high flow velocity in closure gap and excessive gap width. Therefore, we used the synchronous closure of many narrow closure gaps to solve the problem that the closure gaps in over -sized surrounding area cannot close quickly and safely. According to the demonstration in Hengsha East Shoal Reclamation Project (Phase VIII) , the result shows: by taking the mathematical model calculation as guide, reasonably setting many closure gaps, adopting the combined rockfill dam and filling bag technologies and the synchronous closure of many closure gaps, the closure gaps can be closed in a safe, quick and economical manner, the closing difficulty of closure gap in over-sized surrounding area can be relieved and the cost-efficient merit is obvious. It is worth to be widely applied to similar projects. [ABSTRACT FROM AUTHOR]

The main pier pile caps of the channel bridge for river-sea direct ships of the Hongkong-Zhuhai-Macao Bridge are constructed with bottom steel boxed cofferdam construction. The meteorological hydrological conditions of the bridge site are complex, pile caps is big volume, a variety of embedded devices, anticorrosive demand is high, we adopted the bottom boxes and combined with the anti-collision structure. The casing and the bottom plate are subdivided, and the whole assembly of the box is finished and transported to the site and the floating crane is hoisted. The platform adopts the underwater concrete cover, and the weight of the bottom concrete, the box side mould and the bottom plate are all borne by the fine steel. The construction method provides reference for subsequent construction. [ABSTRACT FROM AUTHOR]

Based on the levelling construction of quay 28 caisson bedding in Ashdod Port project, Israel. Since the traditional construction method based on the manpower of divers is restricted to various conditions, the construction efficiency could hardly meet the requirement of milestone. We carried out the research on improving levelling technology, and formed the research results of hydraulic underwater levelling equipment, which can increase construction efficiency and save the expense for divers, as a reference for similar rock bedding levelling projects. [ABSTRACT FROM AUTHOR]

As development of economic trade and tourism, the construction of deep water port and offshore artificial island become more important. Projects in which dredgers excavate stony soil are increasing greatly, and TSHD dredging this kind of material is an international technical problem so far. We analyzed the difficulties, the adopted measures and the application effects of the TSHD dredging stony soil, which can provide references for the smooth implementation of similar projects in the future. [ABSTRACT FROM AUTHOR]

Based on the 12.5 m deep-water channel construction phase 域of the Yangtze River below Nanjing city, first successful application of construction technology of deep water filling bagged sand dike core of the deepest depth of -35 m. By optimizing the filling sand bags sewing process, improving the filling sand bags laying process, we realized the application of filling bagged sand dike core construction technology in deepwater construction. The construction technology has improved construction efficiency,enhanced the levee molding accuracy, reduced the consumption coefficient , to ensure project quality. [ABSTRACT FROM AUTHOR]

The main tower box -foundation of CCCC Huitong Hengqin Square project was constructed with mass concrete pouring and tamping technology. According to the technical conditions, construction conditions, and layout, we used an organic combination of "fast" chute, "wide" pump, and "flexible"auto pump, took reasonable technical measures, successfully completed the mass concrete pouring construction of the main tower box -foundation, and found no unusual cracks. It has accumulated relevant technical experience. [ABSTRACT FROM AUTHOR]

Based on the 180 m long-span ultra-high pier top block prefabricated project in the wiring viaduct project at the Hongkong section of the Hongkong-Zhuhai-Macao Bridge, we introduced the pier top block prefabrication technology and the formwork system solution. Through the introduction of a large number of hydraulic synchronization technologies to achieve rapid template system open / close mold control, and improve the prefabricated efficacy. The practice shows that the whole system has high operability, high degree of automation, and has achieved good economic benefits. [ABSTRACT FROM AUTHOR]

The 2 500 ton-50 meter Movable Scaffloding System (MSS) transition construction technology and its application in Wenzhou Oujiang Nankou main bridge are proposed in this paper. After setting the suspension device, the weight of MSS transferred to the bridge floor. Then, the MSS is launched through the main bridge to the predetermined location on the other side of the river through the sliding system of bridge floor. The self-transition method avoided the complicated reassemble construction steps after disassemble of MSS, provided a novel idea for MSS, which need to transition construction on both sides. Only few components of MSS, or none, are dismantled during the transition construction from one side of main bridge to another. The whole transition construction process is automatic, fast and safe, which can provide references for similar engineering. [ABSTRACT FROM AUTHOR]

In order to improve the landscape effect at the entrance of HZMB tunnel, fair-faced concrete is used. Based on the conditions for fair-faced concrete construction at the entrance of HZMB tunnel and by way of determination of the construction scheme and working process and the optimization of the construction technology, the level of fair -faced concrete construction was improved steadily. With the use of high-efficiency and high quality formwork, high-frequency vibrators and high performance concrete, the apparent quality of the fair-faced concrete was significantly improved and such defects as grout leakage, bubbles and pitted surfaces were also avoided. [ABSTRACT FROM AUTHOR]

The composite bridge with corrugated steel webs, which adopted the technology of segmental prefabrication and assembly, is a new composite structure. Since concrete webs replaced by corrugated steel webs, the positioning and connecting process of corrugated steel webs is added. we studied on the key factors influencing the construction efficiency during the segmental prefabrication and assembly for corrugated steel webs in order to adapt the characteristics of the factory manufacture and the mechanical installation. At the same time, we carried out a scale model test to verify the structural performance. The results show that the precast segmental box girders with corrugated steel webs has the same properties with the in-situ structures during normal use, it can meet the engineering application. [ABSTRACT FROM AUTHOR]

Fair-faced concrete is the concrete which is no dealed by only one-casting. It is popular because of its features which are smooth and even uniform color, angular, smooth lines as well as the natural transition between layers and so on. Taking the fair-faced concrete construction of protection wall in east island tunnel of Hongkong-Zhuhai-Macao Bridge as an example, we introduce the construction technology of fair-faced concrete, which has reached the expected effect of construction. [ABSTRACT FROM AUTHOR]

The traversing construction of immersed tube elements is the last step of immersed tube prefabrication. By the cabling design, and the calculation of equipment selection, we developed a comprehensive construction process and the operation method of immersed tube traversing. Actually, the project has been successfully completed the traversing construction of 24 tube elements, which proved the method is high construction efficiency, easy to operate, safe and low construction cost. [ABSTRACT FROM AUTHOR]

The non navigable bridge of the Hongkong-Zhuhai-Macao Bridge east island is a cast-in-situ prestressed concrete box girder, a total of two joints. The second joint was first constructed, adopted twice layered casting construction technology. The technology had been summarized and optimized after the second joint construction finished. Then the first joint adopted the full-section once concreting construction technology, which has optimized the construction technologies of formwork and concrete, and has made big progress in the finished product quality and schedule cost. [ABSTRACT FROM AUTHOR]

The construction of lock project is different from the traditional port or dock construction. Aiming at the concrete structural features and construction difficulties of the lock project, we used the concrete construction technology, which is mainly supported by the gantry crane and supplemented by other various forms. The comprehensive construction measure ensures the construction strength and quality. [ABSTRACT FROM AUTHOR]

Based on the construction of oversize diameter steel sleeve with 4.1 m diameter pile foundation of Jiaxing-Shaoxing Bridge in the Hangzhou Bay waters, we introduced the production, transportation, sinking construction technology and vibration hammer type selection, guide box design, and strengthened design of oversize diameter steel sleeves, and discussed the construction technology and control points of the bridge pile foundation oversize diameter steel sleeves under the complicated hydrological condition in strong tidal waters, which can provide references for similar projects. [ABSTRACT FROM AUTHOR]

In order to reduce or avoid the harmful cracks in pier concrete, we used the finite element software to establish the simulation analysis model according to the actual size of the breast wall, and carried out simulation analysis on different layered block construction processes for wharf parapet respectively. On the basis of comparing and analyzing the change of temperature stress, we studied the optimum construction process of parapet. The results show that there is no harmful crack in the parapet to achieve the expected construction quality and efficiency requirements. [ABSTRACT FROM AUTHOR]

Formwork is very important for construction of fair-faced concrete and its quality is the key to a project. The method for assembling fair-faced concrete formwork is introduced and the technology for construction of formwork for fair -faced concrete is described on the basis of the engineering practice in the construction of fair-faced concrete for the open tunnel walls in the east artificial island of Hongkong-Zhuhai-Macao Bridge. [ABSTRACT FROM AUTHOR]

The excavation construction of gravity wharf rock foundation has the characteristics of low efficiency, high quality requirements, and great difficulty in construction. We studied the construction technology for direct excavation of gravity wharf rock foundation by large cutter suction dredger, which has successfully applied to practical engineering construction. Compared with the traditional reef blasting and reef cleaning, this construction technology has advantages of fast process, reliable quality, safety and environmental protection, it is worthy for stronger application value. [ABSTRACT FROM AUTHOR]

We analyzed the construction techniques of the long-large diameter rock piles in the Non Navigable Bridge, which is in the joint part of east island of the Hongkong-Zhuhai-Macao Bridge island and tunnel project, including the construction technology of large diameter steel casing, application of gas lift reverse circulation, mud ratio and control, hole technology under complicated geological, meteorological, and hydrologic conditions, and the control points of secondary pile hole cleaning, underwater concrete construction technology, and the prevention and treatment -related issues, etc. This paper has high reference value for similar projects. [ABSTRACT FROM AUTHOR]

The main body concrete quantity is about 600 000 m3 of Jialing River Caojie navigation-power junction lock project, it shall be multi-graded half-dry concrete. We discussed the determination of concrete temperature control index, and the construction measures and implementation effect under high temperature conditions, which can ensure the continuous and rapid concrete works under high temperature conditions and the concrete construction quality and progress. [ABSTRACT FROM AUTHOR]