Business Overview

DN Holdings Group is a general construction consultant where a professional group that excels in investigation, design, maintenance and management can respond to increasingly frequent and intense natural disasters, increasingly serious global environmental problems, and existing decaying social infrastructures.

We are aiming to be a “business group trusted by and essential for the society” while continuously expanding the core businesses, taking challenges for exploration of new fields, and developing in a sustainable manner in order to realize the corporate philosophy of “unlock the potentials of earth, space, human beings, and society to create the future”.

Business Overview

Structure field

In the structure field, we are engaged in the design of beautiful bridges and road structures that excel in the safety, durability, and ease of maintenance taking into account various conditions like the region, geography, climate, environment, history, and performances required in the era with our professional design technologies accumulated over many years.
Today, Japanese society has reached a maturity stage and the renewal and maintenance of various social infrastructures including around 700,000 road bridges across Japan has attracted attention as an issue. Moreover, structures have been collapsed and been washed out by unprecedented disasters like unexpected climate phenomena, earthquakes, and tsunamis in recent years, which is threatening the lives of people.
In response to the issues and threats, DN Holdings is going to further enhance the system and keep meeting social needs in order to promptly promote the national resilience and efficiency of maintenance while transmitting the technologies we have developed to the next generation as well as developing maintenance technologies utilizing the AI and robots.

  • Leading project of reconstruction after the Great East Japan Earthquake
    (Kesennuma Bay crossing bridge/Miyagi Prefecture)
  • Bridge building taking into account the harmony between structural rationality and landscape
    (Kakamigahara Big Bridge/Gifu Prefecture)
  • Renovation technologies to improve the safety and convenience
    (Sandwich construction method)

Social creation field

In the social creation field, we are engaged in the research, design, and supervision of national resilience, environmental impact reduction, and sustainable town development of compact plus network from the perspectives of “road”, “town”, and “environment” surrounding them in order to meet the social needs such as countermeasures against increasingly frequent and intense disasters due to climate changes, conversion to “new lifestyles” against COVID-19, and acceleration of efforts toward smart cities against the background of declining birthrate, aging population, and declining population.
In order to realize an affluent, safe, and secure economic society and lifestyle, we are going to keep on contributing to the development of comfortable and affluent lifestyles and society in terms of time, space, and livelihood by utilizing ICT technologies such as IoT/big data/5G/AI realized by the evolution of digital technologies in recent years to “visualize” issues and completion images as well as solving regional issues while confronting the resources such as unique history, culture, nature, and human resources developed by the region.

  • Road reconstruction in response to the Northern Kyushu Heavy Rainfall in July 2017
  • The station square renaissance development plan aiming for a bustling space

National land conservation field

The recent activities in the Japanese national land conservation field are, with a view to SDGs, shifting to the development of organizations capable of responding to increasingly intense natural disasters against the background of the increased awareness of the environment in society such as the United Nations Conference on Environment and Development “Rio Summit” in 1992, Kyoto Protocol in 1997, Millennium Development Goals (MDGs) adopted in 2000, and Sustainable Development Goals (SDGs) adopted in 2015.
We are taking on challenges in a variety of technology fields such as improvement of rivers and banks where people interact with natural environments, development of coastal environments friendly to ecosystems of the sea and coast, design of sewerage facilities to prevent water pollution, development of tunnels to avoid large-scale excavation in mountains and forests, and measures against aging of the facilities, in order to develop technologies for creating affluent, safe, and secure living environments.
Moreover, we are providing technologies as tangible measures like the raising of river and coastal banks, their earthquake resistance enhancement, earthquake resistance improvement of sluice gates and land locks, sand control facility development such as channel works, earthquake resistance improvement of sewerage facilities, and landslide countermeasures, as well as technologies as intangible measures like a variety of hazard map plans and timeline plans as disaster prevention plans.

  • Landscape-conscious bank harmonized with water
  • Coastal bank resistant to increasingly massive typhoons

Energy facilities conservation field

In the Energy facilities conservation field, we are visualizing the deep underground area utilizing technologies to investigate and analyze geology, ground, and groundwater, and contributing to the realization of the stable supply of energy through conservation of power generation facilities and underground energy storage facilities and a carbon neutral society through efforts toward CCS (Carbon dioxide Capture and Storage).
Five oil and oil gas storage bases which adopted a bedrock tank method are in operation in Japan as underground energy storage facilities, all of which are contributing to the maintenance and management of water sealing functions. In particular, the Namikata National Oil Gas Storage Base is contributing to geology investigation, design and construction supervision, and is going to maintain and manage water sealing functions into the next half century.
In the field of CCS, we are going to be engaged in the land suitability investigation where the suitability of strata for underground storage of CO2 is assessed by combining geological structure data and several types of exploration information and the consideration of monitoring methods to monitor the storage of CO2 pressed into strata.

  • A plane view of Namikata National Oil Gas Storage Base
  • A conceptual diagram of subseafloor CO2 storage
    (Source: Ministry of the Environment: Efforts toward the realization of carbon neutral society utilizing CCUS)

Ground investigation and analysis fields

We propose high-value-added investigations suitable for various problems through investigation technologies for geology, ground, and groundwater accumulated over many years. Moreover, we provide adequate support for the planning, analysis, and assessment of various analysis projects with 3D technologies as well as preparation of various manuals and standards.

【Ground investigation technology】

■Active fault investigation

-Investigation of active faults enables prediction of earthquakes-
Investigation of active faults enables prediction of the scale, damage, and occurrence cycle of the earthquake that occur.

■Three-dimensional reflection method seismic exploration

-Exploration of fault and strata distribution situation-
Information such as strata boundaries and fault locations is grasped visually by generating minimal seismic waves artificially and analyzing the reflected waves.

  • Trench excavation section
  • Semi-transmissive display three-dimensional data

【Analysis technology】

■Three-dimensional infiltrated water analysis

A detailed groundwater flow model for three-dimensional visualization is created to examine the problems related to groundwater flow.

■Two-dimensional flood simulation of debris flow, etc.

Hazard maps on mountain streams which have various geographic and geological structure conditions are prepared to conduct simulations such as disaster examination in target areas and assessment of countermeasure facility effects.
The simulation results are used also to estimate the damage and examine the business effects.

  • Three-dimensional infiltrated water analysis example (trajectory diagram)
  • Debris flow analysis example

Websites of operating companies shall be referred to for details of each group company
(another window will open if you click the links below).

  • NIPPON ENGINEERING CONSULTANTS
  • DIA CONSULTANTS