日本海洋サービス List of Products and Services

We implemented the "Temporary Closure LPF Method" at the Mikai Bridge over the Otsu River in Oita City, Oita Prefecture. We established an earthen embankment within the river to enclose the bridge pier and carried out material delivery and construction using a small crawler crane. Due to the low space under the girder and the strong winds at the site, we adopted a small crawler crane to enhance lifting capacity and mobility. 【Case Overview】 ■ Temporary Closure Shape: Circular φ8.5m H=5.0m ■ Client: Oita Prefecture (Construction in FY 2017) ■ Construction Location: Mikai Bridge, Otsu River, Oita City, Oita Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At Yokoyama Bridge on the Tenryu River in Tenryu Ward, Hamamatsu City, Shizuoka Prefecture, the "temporary cutoff LPF method" was implemented. Due to heavy traffic and the difficulty of occupying the road, materials were transported and construction was carried out using a spud-type steel barge equipped with a crab crane. Since the water depth is about 10 meters and the buoyancy is large, a method of filling the space between the liner plate and the footing with water-stopping concrete was adopted. [Case Overview] ■ Temporary cutoff shape: Circular φ9.5m H=12.5m ■ Client: Hamamatsu City (Construction in fiscal year 2017) ■ Construction location: Yokoyama Bridge, Tenryu River, Tenryu Ward, Hamamatsu City, Shizuoka Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Kitai-mazaike Bridge in Himeji City, Hyogo Prefecture, the "Temporary Closure LPF Method" was implemented. The bridge pier in the central part of the river, where the water depth is shallow, was constructed. Materials were transported using a combination of a rough-terrain crane and a simple floating barge from above the bridge deck. 【Case Overview】 ■ Temporary closure shape: Circular (3 units) φ7.5m H=6.5m ■ Client: Hyogo Prefecture (Construction in fiscal year 2016) ■ Construction location: Kitai-mazaike Bridge, Himeji City, Hyogo Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Sagara Bridge on the Hagima River in Makinohara City, Shizuoka Prefecture, the "Temporary Cofferdam LPF Method" was implemented. Due to the high volume of road traffic and the difficulty of occupying the road, materials were transported and construction was carried out using a steel barge and a crab crane. Since the diameter of the temporary cofferdam is 12.4m, which is larger than the existing footing, a method of filling the gap with water-stopping concrete was adopted. 【Case Overview】 ■ Temporary Cofferdam Shape: Circular φ12.4m H=7.0m ■ Client: Shizuoka Prefecture (Construction in FY 2016) ■ Construction Location: Sagara Bridge, Hagima River, Makinohara City, Shizuoka Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Asashio Bridge over the Asashio Canal in Harumi, Chuo Ward, Tokyo, the "Temporary Closure LPF Method" was implemented. The bridge pier in the shallow central part of the river was constructed. Materials were transported using a combination of a rough-terrain crane from the bridge deck and a simple floating barge. 【Project Overview】 ■ Temporary closure shape: Circular (3 units) φ7.5m H=6.5m ■ Client: Tokyo Metropolitan Government (Construction in fiscal year 2015) ■ Construction location: Asashio Bridge, Asashio Canal, Harumi, Chuo Ward, Tokyo *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Nishimasuda Ohashi Bridge on the Takatsugawa River in Masuda City, Shimane Prefecture, the "Temporary Closure LPF Method" was implemented. The bridge pier in the shallow central part of the river was constructed. A mobile crane and a simple floating barge were used for material transport. Due to the fast water flow, the upstream vertical beams were installed first, and the vertical beams were slid to accommodate the lowering of the liner plates. 【Case Summary】 ■ Temporary Closure Shape: Circular φ9.5m H=8.5m ■ Client: Shimane Prefecture (Construction in FY 2015) ■ Construction Location: Nishimasuda Ohashi Bridge, Takatsugawa, Masuda City, Shimane Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Nozomi Bridge over the Ariake Canal in Odaiba, Minato Ward, Tokyo, we implemented the "temporary cutoff LPF method." We constructed a temporary cutoff exceeding a water depth of 10.0 meters. Materials were loaded onto a barge and constructed from the water's surface using a small crane. Due to the depth and water pressure, we enhanced the strength of the liner plates and vertical beams to accommodate the conditions. [Case Overview] ■ Temporary cutoff shape: oval (2 units) φ7.0m L=31.0m H=12.5m ■ Client: Tokyo Metropolitan Government (Construction in fiscal year 2015) ■ Construction location: Nozomi Bridge over the Ariake Canal, Odaiba, Minato Ward, Tokyo *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Shojin Bridge over the Hanamuro River in Ami Town, Ibaraki Prefecture, the "Temporary Closure LPF Method" was implemented. Construction was carried out in a narrow space of approximately 2.3m under the girder. Materials were transported using a small mobile crane and a simple floating barge from above the bridge deck. 【Case Overview】 ■ Temporary Closure Shape: Oval shape φ4.0m L=16.9m H=5.0m ■ Client: Ibaraki Prefecture (Construction in fiscal year 2015) ■ Construction Location: Shojin Bridge, Hanamuro River, Ami Town, Ibaraki Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the San-no-bashi in Furukawa, Tokyo, the "temporary cutoff LPF method" was implemented. Construction was carried out in a narrow space of approximately 2.0m under the beam. Due to fluctuating water levels, the platform was lowered to a position where it would be submerged, ensuring a suspended space. Assembly was difficult while the liner plates were submerged. 【Case Overview】 ■ Temporary cutoff shape: oval shape φ6.0m L=28.0m H=5.0m ■ Client: Tokyo Metropolitan Government (Construction in fiscal year 2011) ■ Construction location: San-no-bashi, Furukawa, Tokyo *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

At the Kozagawa Ohashi Bridge in Kozagawa, Wakayama Prefecture, the "Temporary Cofferdam LPF Method" was implemented. Due to the influence of waves from the sea, materials were transported using a rough-terrain crane from the road occupying the bridge deck. As a result, work could be carried out without the influence of waves, except for the lowering of the liner plates. 【Case Overview】 ■ Temporary Cofferdam Shape: Circular (4 units) φ9.0m H=7.0m ■ Client: Kinki Regional Development Bureau, Ministry of Land, Infrastructure, Transport and Tourism (Construction in FY 2014) ■ Construction Location: Kozagawa Ohashi, Kozagawa, Kushimoto Town, Higashimuro District, Wakayama Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

We carried out the "Temporary Cofferdam LPF Method" at the Nagato Stone Bridge over the Chikugo River in Kurume City, Fukuoka Prefecture. Materials were loaded onto a barge and construction was performed from the water using a small crawler crane. By dividing the workers into two teams and conducting the main tasks simultaneously, we shortened the construction period. 【Case Overview】 ■ Temporary Cofferdam Shape: Circular (2 units) φ11.5m H=9.0m ■ Client: Fukuoka Prefecture (Construction in fiscal year 2014) ■ Construction Location: Nagato Stone Bridge, Chikugo River, Kurume City, Fukuoka Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

We implemented the "Temporary Closure LPF Method" at the Outer Kago Bridge over the old Yoshino River in Tokushima City, Tokushima Prefecture. The work was carried out in a narrow space of approximately 2.0m under the girder. Materials were loaded onto a barge and transported from the water using a crab crane. The position of the lifting device was moved to the top of the bridge pier to accommodate the lifting work. 【Case Overview】 ■ Temporary Closure Shape: Oval shape φ5.2m L=7.5m H=5.5m ■ Client: Tokushima City (Construction in FY 2015) ■ Construction Location: Outer Kago Bridge, old Yoshino River, Tokushima City, Tokushima Prefecture *For more details, please download the PDF or feel free to contact us.

• Bridge Construction

The temporary cutoff LPF method is a temporary cutoff construction technique that uses liner plates to build a temporary cutoff structure, aimed at bridge pier reinforcement and repair work. It has over 90 construction records nationwide in underwater environments such as rivers, seas, and dams, and has been applied to more than 110 bridge piers. This method adopts a technique where a tubular liner plate structure is assembled above water and then installed underwater. It allows for the selection of shapes according to site conditions while minimizing excessive custom component manufacturing for each bridge pier, contributing to shortened processes, rationalized construction planning, and securing holidays. 【Features】 ■ Composed of liner plates, H-beams (reinforcement rings), and supports ■ Above-water assembly and underwater installation method ■ Construction possible with low headroom (approximately 1.0m) ■ Manual construction compatible, can be executed under heavy machinery restrictions ■ Vibration-free construction reduces impact on the surrounding environment *Method comparison materials and construction case studies can be viewed in PDF format.

• Renovation and repair methods

In bridge pier reinforcement work, the use of heavy machinery may be restricted due to site conditions and surrounding environments. The temporary cutoff LPF method accommodates manual construction, allowing assembly and installation even in low headroom and narrow spaces. It is utilized as a practical temporary cutoff method even at sites with construction constraints. *Please refer to the materials that include examples of manual construction. 【Features】 ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Suitable for low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

In nighttime construction or bridge pier reinforcement work with limited construction periods, the ease of assembling the process is important. The temporary cutoff LPF method features a simple component structure and allows for shape selection according to site conditions, making it easy to organize the construction steps. It is being considered as an option for sites looking to shorten the construction process. *You can check the process comparison materials in PDF format. 【Features】 ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Suitable for low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

In bridge pier reinforcement work where the workspace is limited, the selection of the temporary cutoff method influences the feasibility of construction. The temporary cutoff LPF method can accommodate manual construction and can be assembled and installed even under low headroom and narrow conditions. It is easy to introduce even in sites where heavy machinery usage is difficult, expanding the options for construction planning. *Construction achievements in low headroom sites are documented. 【Features】 ■Temporary cutoff structure using liner plates ■Above-water assembly and underwater installation method ■Compatible with low headroom and narrow areas ■Construction that suppresses vibrations is possible

• Renovation and repair methods

In the seismic reinforcement and longevity enhancement project for existing bridges, a construction plan that utilizes existing structures is required. The temporary closure LPF method can be implemented even in narrow conditions and low headroom environments, making it a chosen temporary closure method for seismic reinforcement work. By minimizing custom components, it also contributes to the overall project schedule management. *Examples of its application in seismic reinforcement work are included. 【Features】 ■ Temporary closure structure using liner plates ■ Above-water assembly and underwater installation method ■ Suitable for low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

In reinforcement work for harbor areas and offshore bridge piers, consideration for surrounding facilities and navigation environments is essential. The temporary cutoff LPF method adopts a structure that allows for vibration-free construction, achieving temporary cutoff work that takes into account the marine environment. It also accommodates manual construction, making it an easy-to-implement method even in harbor areas with limited working space. *Please check the construction examples of harbor and offshore work. 【Features】 ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Suitable for low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

The temporary cutoff LPF method is a construction technique that allows for work on the reinforcement and repair of bridge piers in rivers, taking into account water level fluctuations and work constraints. After assembling the tubular structure above the water surface, it is installed underwater, enabling construction to proceed while minimizing impact on the river environment. It can accommodate low headroom conditions and narrow river cross-sections, and is used in maintenance and management work for river bridges. *Case studies of construction in river projects are available. 【Features】 ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Accommodates low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

The temporary closure LPF method is a construction technique aimed at shortening construction periods and improving work efficiency through the rationalization of component composition. By reducing custom manufacturing for each pier, it contributes to the leveling of preparation time and on-site work. As a result, it also leads to easier process management and a reduction in the burden on workers. *Please view the comparison materials and process image materials in PDF format. [Features] ■ Temporary closure structure using liner plates ■ Above-water assembly and underwater installation method ■ Compatible with low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

The temporary cutoff LPF method is a temporary cutoff construction method that can accommodate various design conditions such as pier shape, water area conditions, and headroom restrictions. Based on standardized components, it allows for shape selection tailored to the site, contributing to a reduction in the design phase workload. It is adopted as a practical temporary cutoff method in bridge reinforcement and seismic reinforcement design. *We have prepared materials that can be utilized during the design review phase. 【Features】 ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Compatible with low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

In bridge repair and reinforcement work, what is important is the reliable temporary closure construction in a limited working space. The temporary closure LPF method adopts a structure that can be assembled and installed even in narrow areas and low headroom conditions. Due to vibration-free construction, it is possible to ensure both safety and workability while minimizing the impact on existing structures. *Please refer to the case study collection that includes examples of its use in reinforcement work. 【Features】 ■ Temporary closure structure using liner plates ■ Above-water assembly and underwater installation method ■ Compatible with low headroom and narrow areas ■ Vibration-reduced construction is possible

• Renovation and repair methods

The temporary cutoff LPF method is a construction method designed with a focus on workability, taking into account the constraints of the construction site. Since it allows for shape selection based on site conditions, it helps to minimize excessive design changes and component fabrication for each pier. It is also compatible with manual construction, enabling flexible construction plans even in environments where heavy machinery cannot be used. *You can check the method comparison materials and construction flow materials in PDF format. [Features] ■ Temporary cutoff structure using liner plates ■ Above-water assembly and underwater installation method ■ Low headroom and narrow area compatibility ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

The temporary cutoff LPF method is a temporary cutoff construction technique designed for reinforcing underwater bridge piers in rivers, seas, and dams. It is adopted in public bridge maintenance and longevity projects due to its adaptability to various site conditions. By minimizing the use of custom components, it shortens the construction process and contributes to clarifying the construction period and promoting planned project advancement. *We have prepared materials summarizing case studies of construction in public works. 【Features】 ■ Temporary cutoff structure using liner plates ■ Assembly above water surface and installation underwater ■ Suitable for low headroom and narrow areas ■ Construction that minimizes vibrations is possible

• Renovation and repair methods

The "Temporary Closure LPF Method" is a temporary closure method that has been adopted in various underwater environments such as rivers, seas, and dams. Since it allows for the selection of the optimal shape according to site conditions, it enables flexible construction plans even in sites with spatial constraints that are difficult to address with conventional methods. It is also compatible with manual construction, making it easy to implement even in bridge pier reinforcement work where headroom restrictions are strict. *For details, please refer to the construction case collection and method comparison materials. 【Features】 ■ Temporary closure structure using liner plates ■ Above-water assembly and underwater installation method ■ Suitable for low headroom and narrow areas ■ Construction that suppresses vibrations is possible

• Renovation and repair methods

The temporary closure LPF method is a construction method focused on efficiency in the temporary closure work for underwater pier reinforcement projects. It allows for shape selection tailored to site conditions, reducing excessive custom manufacturing for each pier, thereby achieving shortened construction periods and reduced work burdens. Since manual construction is possible even in environments where heavy machinery cannot be used, it can be applied in sites with a headroom restriction of about 1.0m. *Method comparison materials and construction case studies can be viewed in PDF format. 【Features】 ■ Structure assembled in a tubular shape installed underwater ■ Usable in low headroom and narrow spaces ■ Vibration-free construction considerate of the surrounding environment ■ Contributes to securing holidays through process shortening

• Renovation and repair methods

The "Temporary Closure LPF Method" is a well-established technique for constructing temporary closures using liner plates in underwater structures such as rivers, seas, and dams. By minimizing custom components for each pier and allowing for shape selection based on site conditions, it contributes to shortening the construction process and ensuring stable construction quality. It is also compatible with manual construction, having numerous successful projects even in sites with strict headroom restrictions (approximately 1.0m). *Please take a look at the collection of case studies summarizing our construction achievements. 【Features】 ■ Composition of liner plates + H-beam reinforcement rings + support structures ■ Assembled above water and then installed underwater ■ Compatible with narrow and vibration-free construction ■ Usable even under low headroom conditions

• Renovation and repair methods

The "Temporary Closure LPF Method" is a construction method for building temporary closures of underwater structures such as rivers, seas, and dams using liner plates. The Temporary Closure LPF Method contributes to shortening construction periods and ensuring holidays through the following means: - Reducing the production of custom components for each pier - Selecting suitable shapes based on site conditions It can be implemented using manual labor alone and is feasible in environments with a headroom restriction of approximately 1.0 meters or less. *Please refer to the case study collection that includes examples of the construction achievements of the "Temporary Closure LPF Method." 【Features】 ■ Composed of liner plates, H-beams (reinforcement rings), and supports ■ Assembled in a cylindrical shape above water and installed underwater ■ Construction is possible with a headroom restriction of approximately 1.0 meters! *Record: 1.2m ■ Vibration-free construction is possible in narrow spaces! *For method comparison materials and construction case studies, please download the PDF to view.

• Renovation and repair methods

The "Fully Wet Type Underwater Wire Sawing Method" is a technique that allows for the cutting and removal of underwater concrete structures in a space-saving manner. Only diving operations are conducted for installation and removal, and the machinery operates unmanned, significantly reducing the risk of personal injury. Additionally, since it is directly installed on the underwater structure, there is no impact from vibrations or waves, and it can be executed with a diamond wire of the minimum necessary length. The use of biodegradable oil for operational purposes minimizes pollution to human health and water quality. *This handbook includes the construction methods, workflow, and equipment used for the "Underwater Wire Sawing Method." [Contents] - Features - Construction Overview Diagram - Wire Detail Diagram - Cutting Overview Diagram, etc. For more details, please refer to the catalog or feel free to contact us.

• Civil Engineering Method
• River construction
• Coastal construction

The "Temporary Closure LPF Method" is a construction method that builds temporary closures for underwater structures such as rivers, seas, and dams using liner plates. It addresses the issues of conventional closure methods and supports bridge pier reinforcement with "simplicity, speed, and excellent water-stopping ability." It can be implemented using only manual labor. This groundbreaking NETIS registered method can be used in environments with a headroom restriction of 1.5 meters or less! Please feel free to contact us for more information! *Currently, we are offering a collection of case studies featuring the construction results of the "Temporary Closure LPF Method" for free exclusively to Ipros users! 【Features】 ■ Composed of liner plates (waterproof specifications), water-stopping rubber gaskets, H-steel (reinforcement rings), and cutting beams ■ Can be implemented using only manual labor! ■ Construction is possible with a headroom restriction of about 1.5 meters! ■ Vibration-free, allowing construction close to existing structures (gas, electricity, water pipes, etc.)! ■ NETIS registered: CB-110010-VE (patent) *For more details, please refer to the catalog. Feel free to contact us with any inquiries.

• Renovation and repair methods
• River construction
• Earthquake-resistant construction method

The completely wet-type underwater wire saw method is a technique for cutting and removing structures such as concrete underwater during demolition. It allows for space-saving operations at great depths and is not affected by working depth (working depth from 0m to 45m). Since the wire saw machine is entirely installed underwater, there are no human-related accidents, and because the cutting machine itself is underwater, operations can continue even if the work vessel is swaying. It can be constructed with a minimal length of diamond wire for cutting, and due to the compact size of the machine, CO2 emissions are significantly reduced. 【Features】 - Equipment can be loaded onto a small vessel for preliminary cutting. - Monitoring is done via surveillance cameras, allowing for immediate response to any issues. - Biodegradable oil (ISO 6743 Class L) is used for operational fluids. - NETIS registration number KKK-090001-A (registration period has ended). For more details, please contact us or download the catalog.

• Civil Engineering Method
• River construction
• Coastal construction

The excavation and removal method using MJP generates no contaminated water, resulting in minimal environmental impact. It can achieve approximately 90% suction of the main diameter, allowing for long-distance transport of excavated soil and other materials (with a maximum transport record of 450 meters). Additionally, since the driving water can be reused, it can increase the mud content in the sedimentation area. 【Features】 ■ No contaminated water is generated, resulting in minimal environmental impact ■ Approximately 90% suction of the main diameter is possible ■ Long-distance transport of excavated soil and other materials is possible ■ Driving water can be reused ■ It is possible to increase the mud content in the sedimentation area For more details, please refer to the catalog or feel free to contact us.

• Coastal construction
• Drilling Machine
• River construction

The "Stirring Type Casing Pump Excavation Method" is an underwater excavation method that performs excavation, piping, and transportation within the casing, suppressing the generation of muddy water during excavation and transportation. By changing the equipment, excavation can be performed in narrow spaces. Additionally, excavation is possible in locations where large machinery cannot be used. 【Features】 ■ Underwater excavation method ■ Excavation, piping, and transportation within the casing ■ Suppression of muddy water generation during excavation and transportation ■ Excavation possible in narrow spaces with equipment modification ■ Excavation possible in locations where large machinery cannot be used For more details, please refer to the catalog or feel free to contact us.

• Coastal construction
• Civil Engineering Method
• Earthquake-resistant construction method

The "Underwater Stud Welding System" is a system that can manage the welding condition for each bolt and allows for space-saving operations. At Nihon Ocean Services Co., Ltd., we have been researching and exploring methods for efficiently and safely dismantling structures in underwater environments that were previously impossible. This system enables groundbreaking high-efficiency work and safe construction, shortening construction periods and reducing CO2 emissions by up to 1/11. 【Features】 ■ Capable of installing headed studs, deformed rebar studs, and threaded studs ■ Real-time monitoring of current waveforms allows for quality control of each individual stud ■ Equipment can be arranged in a space-saving manner ■ The compact size of the machinery significantly reduces CO2 emissions For more details, please refer to the catalog or feel free to contact us.

• Coastal construction
• Civil Engineering Method
• Renovation and repair methods

At Nippon Marine Service Co., Ltd., we not only carry out various special construction projects but also engage in many underwater construction works, surveys, and environmental measures, all conducted safely. For construction in underwater environments such as rivers and seas, trust "Nippon Marine Service," which possesses special techniques and methods (such as underwater wire sawing and temporary cutoff LPF methods). For more details, please refer to our catalog or feel free to contact us.

• Coastal construction
• River construction
• Harbor Construction

The "Real-Time Carbon Monoxide Detection Device" is a safety device that detects the concentration of carbon monoxide in the supplied air and alerts users through an alarm sound and rotating light. 【Features】 ■ It detects and quantifies undetectable carbon monoxide using sensors, visualizes the concentration of contamination, and alerts users to prevent carbon monoxide poisoning. ■ NETIS Registration Number: KKK-110001-A (Patent) For more details, please refer to the catalog or feel free to contact us.

• Coastal construction