Story of Daiho (our history)

Reading and understanding Daiho Corporation from History
  • 1936
    First technology verification at the Fengman Dam.
    Fengman Dam

    The Second Songhua River in the former Manchuria with a width of 700m-800m. In 1936, a project was launched to build the "Fengman Dam" on it. It was a concrete gravity dam with an embankment length of 1,100 m , a height of 91 m, a crest width of 8 m, a volume of 2.2 million cubic m and a foundation excavation volume of 1.9 million m3, making it the world's largest dam after the Hoover Dam and Boulder Dam (as they were known at the time of construction).
    In 1939, cofferdam construction on the left bank began. However, underwater concrete construction in the extreme cold was very difficult. Snake baskets, boulders, and other obstacles froze on the river bottom on the way to the connection of the right bank cutoff, and were not easily removed.

    To improve the situation, we decided to use pneumatic caisson technology. The idea was to sink a simple pneumatic caisson to the bottom of the river to remove any obstacles, and then to place concrete to fill the bottom of the caisson and make it part of the watertight wall. The engineers involved in the construction of this dam are the founders of Daiho Corporation. Since our founding, we have consistently refined our technological strength and built the backbone of the construction industry with innovative technologies.

  • 1949
    Established Daiho Corporation on March 31, 1949 with capital 5 million yen
    More than half of the employees were members who were involved in dam construction in Manchuria and Taiwan, including the founders, Koshi Uchida and Uhachi Kaetsu. Registered as a construction company under the Construction Business Act (Registration No. (i) No. 20)
  • 1951
    The Daiho Method of Submerged Tube Construction, a patented method with enhanced safety and efficiency led to being awarded the Purple Ribbon Medal.
    Daiho Method of Submerged Tube Construction

    A series of large-scale natural disasters, including the Makurazaki typhoon in 1945, encouraged a government-led flood control project for major water systems in 1949, prompting a shift to a multi-purpose dam system, including water resource development. At the same time, the Tone River in Gunma Prefecture, which suffered typhoon damage for three consecutive years, experienced flooding of its main stream and tributaries, causing extensive damage to nearby areas. Daiho Corporation began construction work on the revetment in 1948, but the large typhoons hitting the area every year caused damage. We determined that the problem could not be addressed by existing construction methods. Then, an on-site chief engineer proposed the Simplified Caisson Method devised at the Fengman Dam , and it was adopted for the first time in the postwar period for revetment construction.

    In 1952, we obtained a patent for the "Daiho Caisson Method" as a "method for constructing concrete structures in submerged or spring water strata.“ Mr. Uchida, who devised the "Simplified Caisson Method” at the Fengman Dam, received the Purple Ribbon Medal in 1959.

  • 1953
    Participated in a number of dam-related construction projects following the promulgation of the " Electric Power Development Promotion Act (1952)
  • 1954
    Participated in many weir and harbor construction projects from 1954 to 1956 as a construction company with Caisson Method
  • 1962
    Listed on the Second Section of the Tokyo Stock Exchange
  • 1963
    Construction with the first shield method begins
    Shield Method was adopted for pipeline construction in Tokiwa-bashi district and Otemachi in Chiyoda-ku, Tokyo
    “Reverse Circulation Drilling (RCD) method” was adopted for the first time in Japan as a private construction method for cast-in-place concrete piles during the foundation of the Tokyo Monorail marine viaduct.
  • 1964
    The first overseas construction project (construction of the Voshmgir Dam in Iran) begins
  • 1966
    Developed the "Dolphin Dock (DD) method" for Naoetsu Port harbor renovation work. Later, patent published (1971)
  • 1971
    Capital increased to 1.2 billion yen
  • 1972
    Listed on the First Section of the Tokyo Stock Exchange. Head office building completed near Eitai-bashi bridge on the Sumida River.
  • 1973
    Capital increased to 1.7 billion yen
  • 1976
    Developed and adopted the "Mud Compression (DK) Shield Method" for public sewage works in Aoto 4-chome and 5-chome, Katsushika-ku, Tokyo
  • 1978
    Capital increased to 2.1 billion yen
  • 1984
    The first overseas subsidiary (Thai Daiho Company Limited) is established on the occasion of the civil engineering preparatory work and the construction of the diversion tunnel of the Chiew Larn multi-purpose Dam and a patent is registered for the Mud-pressure Shield Method.
  • 1987
    The technological achievements of Daiho Construction supported the urban development
    Technological achievements of Daiho Construction

    The Daiho Pneumatic Caisson Method was revolutionary. It used an airlock in a double-slab structure made of reinforced concrete to carry out excavated earth and perform pressurization and depressurization. However, with declining steel costs and other factors, steel locks became popular for on-site installation due to their simplicity. The Daiho Pneumatic Caisson Method fell out of fashion. At this time, a project to build a huge suspension bridge in the Tokyo Bay area emerged. Amidst increasing demand for further safety assurance, work environment improvement, and cost reduction, our pneumatic caissons were extended to greater depths and large-scale caisson construction increased, leading to the adoption of double slabs as the Japanese foundation for suspension bridges.

    This suspension bridge, named the Rainbow Bridge, has become an essential part of Tokyo's transportation system. In the same year, we began developing an unmanned excavation method using a full-scale remote-control system. We embarked on further technological development. The demonstration experiment conducted the following year was a success. The technology was named the “DREAM Method (unmanned excavation method)”.

    Patent registered for the DOT Shield Method (multiple mud-pressure shield method).
  • 1989
    Developed unmanned caisson construction method, the "DREAM (Daiho Remote Control Excavator Automatic Method)" The first construction using the DOT construction method began
    DOT (Double-O-Tube) construction method, jointly developed with Obayashi Corporation and Taisei Corporation, was adopted for the construction of the National Route 54 new traffic system (Hiroshima city)
  • 1990
    Designated as a margin trading issue on the Tokyo Stock Exchange. Developed DPLEX (eccentric multi-axis) construction method.
  • 1991
    Capital increased to 5 billion yen
  • 1992
    Patent registered for the DPLEX Shield Method (arbitrary cross-sectional surfaces construction shield method).
  • 1993
    Construction of Rainbow Bridge is completed, and a patent is registered for the DREAM Method (pneumatic caisson unmanned excavation method).
  • 1994
    The Rainbow Bridge: The Japan Society of Civil Engineers Tanaka award for creative construction
    The world's first square shield construction method (DPLEX (eccentric multi-axis) method) was adopted for the sewerage works in Narashino city. This rational and economical method developed in 1990 to meet the rapidly advancing need for advanced utilization of urban underground space received the "Civil Engineering Technology Development Award” in 1996.
  • 1995
    Received the Order of the State "Officier" for our contributions to national projects over the years (Republic of Madagascar)
  • 1997
    During the construction of the Mabechi-gawa River bridge (substructure construction) on the Tohoku Longitudinal Expressway between 1997 and 1999, we renewed the conventional Daiho Pneumatic Caisson Method and adopted the newly developed "New Daiho Pneumatic Caisson Method” (the current New DREAM Method).
    Challenge to achieving complete unmanned operation
    Challenge to achieving complete unmanned operation

    In 1997, the conventional "Daiho Pneumatic Caisson Method” was renewed. “DREAM II Multi-functional Caisson Excavator” was developed, which can be remotely operated, to excavate a wide range of soil types, from clay to sand and gravel layers and bedrock. This has further improved the working environment and other aspects of workers' lives, enabling them to work safely and securely. Rock excavation was successfully completed by adopting this technology in the construction of Mabechi-gawa River Bridge (substructure construction) on the Tohoku Longitudinal Expressway in the same year.

  • 1998
    Patent registered for the RUP Construction Method.
  • 1999
    The 50th anniversary of the establishment of the Hakucho Ohashi Bridge:The Japan Society of Civil Engineers Tanaka award for creative construction. Patent registered for J-DPLEX shield method.
  • 2002
    Patent registered for the DAPPI Construction Method.
  • 2003
    Patent registered for the New DREAM Construction Method.
  • 2004
    Kitakami Ohashi Bridge: The Japan Society of Civil Engineers Tanaka award for creative construction. Increased construction of condominiums and office buildings due to a boom in private-sector construction investment. Our "Mud-pressure Shield Method" construction projects exceeded 1,000, accounting for 70% of all shield construction in Japan.Patent registered for the reversed placement of underground road tunnels; patent registered for the DRES Construction Method.
  • 2006
    Port construction adopted for Madagascar's banknote
    Banknote of Madagascar

    We have had a deep relationship with the Republic of Madagascar since 1977, when we participated in the Namorona power plant project as an Official Development Assistance (ODA) project. Since then, we have been involved in many infrastructure facilities, including road construction and water supply projects. In 2006, we engaged in the "Comprehensive Growth Project, District Port of Ehoala Construction Work" (Port of Ehoala project). It was construction of a new port with a quay depth of 17.4 meters to offload the titanium ore reserves near Fort-Dauphin, southeastern Madagascar, into Galison bay.

    Although the design and construction period for the quay portion of the project was only 1,000 days-- too short for a work of this scale, handover was successfully completed within the time frame. This project was highly acclaimed, receiving the 2010 "Project Excellence Award" by COPRI, a suborganization of the American Society of Civil Engineers. The port has also been adopted as the design for the 2017 Madagascar banknote.

    Patent registered for the installation of covering plates with fastening clips.
  • 2008
    Patent registered for the DEFIMA Construction Method; patent registered for the DASH Construction Method.
  • 2009
    The 60th Anniversary of the Yabe-gawa River Ohashi Bridge: The Japan Society of Civil Engineers Tanaka award for creative construction, "Port of Ehoala project" in Madagascar: the 2010 "Project Excellence Award" by the American Coasts, Oceans, Ports, and Rivers Institute (COPRI)
    Completion of a great deep shaft using the Double-slab Pneumatic Caisson Method
    Completion of a great deep shaft

    The Double-slab Advanced Unmanned Pneumatic Caisson and NewDREAM Method are used to not only perform unmanned excavation by remote control, but also daily inspection and maintenance of the excavator at atmospheric pressure, achieving a significant reduction in work under high pressure and preventing health hazards due to compressed air. In addition, an unmanned ground test was conducted upon completion of the settlement to confirm the ground bearing capacity and completed the shaft at great depth.

  • 2010
    Patent registered for the Anchored Caisson Method.
  • 2011
    March 11, Great East Japan earthquake
    Six days later the disaster, we entered Tanohata-mura village, where we had engaged in fishing port development for many years and began restoration work. Mobilized support and alumni employees from all over Japan to the Tohoku branch. Engaged in restoration and reconstruction work with the support of subcontractors nationwide.
  • 2012
    Patent registered for the RECC Construction Method.
  • 2014
    Capital increased to 6.3 billion yen
  • 2015
    Reviewed personnel system to promote women's activities
    Reviewed personnel system to promote women's activities

    Because of years of public investment decline and the economic downturn triggered by the Lehman Brothers collapse, the construction industry has been restricting the hiring of personnel. As such, there is a shortage of engineers to meet the demand for earthquake reconstruction and the Olympic and Paralympic Games. In 2015, we separated the Human Resources Department from the General Affairs Department to strengthen recruitment. We continue to offer internship and work experience programs to provide an opportunity for people to experience our workplace atmosphere. We have also reviewed the recruitment plan and currently hire around 40 new graduates every year, regardless of the economic climate. We also strive to correct the imbalance in our employee composition.

    In 2006, Daiho Corporation drastically changed its personnel system, introducing a system of promotion according to qualifications and abilities. The number of female engineers has also been increasing gradually since 2012. Some are currently working as site supervisors.

  • 2015
    Capital increased to 9 billion
  • 2018
    Onahama Marine Bridge: The Japan Society of Civil Engineers Tanaka award for creative construction
    Hitachinaka Promotion Office: The 29th Kurose Award in the Construction Category, by Japan Micro Tunneling Assocciation
    Constructed the "New Central Equipment Center" to expand equipment for a variety of pneumatic caisson construction projects.
  • 2019
    70th anniversary of the foundation
    Completion of renovation work on the head office building (the 70th anniversary commemorative project)
  • 2020
    Newly established Institute of Technology--towards the development of new technologies.
    Newly established technical research institute

    With reliable technology to meet our clients’ trust, Daiho Corporation has been contributing to society. We have been involved in many construction projects around Japan. Bridges and structures constructed using the Pneumatic Caisson Method suffered almost no damage in the Niigata earthquake in June 1964 and the Southern Hyogo Prefecture Earthquake in January 17, 1995. Caissons have attracted attention as they proved to be indispensable structures in Japan that are more earthquake-resistant than expected.

    With the newly-established Institute of Technology in 2020, we are moving forward to develop further technologies. Believing that new technology development will support Japan in the future, we will continue to be a creator and developer.

  • 2020
    Capital increased to10.5 billion
  • 2021
    “UNDER RIVER” appeals for underground storage facilities to protect cities from flooding caused by torrential rains.
    Under river

    Torrential rains associated with climate change have increased in recent years, and we recognize the urgent need to minimize damage from flooding in urban areas where underground spaces such as underground malls and subways are expanding. We have been committed to disaster prevention and mitigation projects by utilizing Daiho’s unique and specialized technologies, such as the Pneumatic Caisson Method and Shield Method. A phantom river that appears “UNDER RIVER” only with heavy rainfall is the concept of our underground rainwater storage facility. We created a concept video and a special website to explain the significance of its existence.

  • 2022
    Moved to the Tokyo Stock Exchange Prime Market
    Capital increased to 30.7 billion yen
    Concluded a capital and business alliance agreement with Aso Corporation.
  • 2023
    Decreased capital to 10 billion yen
    Moved to the Tokyo Stock Exchange Standard Market