Research results

Study Tours and New Technology Lectures of 3H Method Held
What is the 3H Method?

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Assembly of a spiral column
Assembly of a spiral column
Participants keenly observing the cross section of a bridge pier
Participants keenly observing the cross section of a bridge pier

Study Tours and new technology lectures on the 3H Method (a new construction technology to build high bridge piers) were held at construction sites at Obara Dam in Shimane Prefecture and Naruse Dam in Akita Prefecture.

Q. What is the 3H Method?
A. The 3H (Hybrid Hollow High pier) Method is a technology to build high bridge piers that offers excellent earthquake resistance and allows reduction of construction periods and cost. The name "3H Method" comes from the fact that the three key phrases characterizing it all begin with the letter H.
Q. What are the characteristics of the 3H Method?
A. The first feature is the spiral column which uses a reinforcement bar made into a spiral and wound around an H steel beam instead of the longitudinal reinforcement bar and the cross tie used for the conventional reinforced concrete bridge piers. In the construction of a bridge pier, more than one of these spiral columns are arranged in a cross section of the bridge pier.
Q. What are positive effects of the 3H Method?
A. The benefits of the 3H Method include the improvement of seismic performance and construction safety and the reduction of cost and construction periods.
* This technology received the JSCE Innovative Technique Award in 2006.

Obara Dam
• Jul. 26th Study Tour: About 60 people took part.
• Jul. 27th New Technology Lecture held in Izumo City, Shimane Prefecture.

Naruse Dam
• Aug. 2nd Study Tour: About 70 people took part.
• Aug. 3rd New Technology Lecture held in Yokote City, Akita Prefecture.

Both Study Tours facilitated an understanding of the method by offering an opportunity to observe how the spiral column, a characteristic of the 3H Method, is assembled on the ground and what the cross section of a bridge pier looks like upon climbing a pier under construction at a construction site.

(Contact : Construction Technology Research Department)

Effect of Endocrine Disrupters on Fish
Male Feminized? Female Virilized?

Rivers in the past: Fish swimming with vigor.
Rivers during the high economic growth period: Rivers become polluted and fish disappear.
Rivers provided with a sewage treatment plant: Fish came back but the effects of hormone disrupters are present.
State-of-the-art sewage treatment plant: Fish swimming with vigor again.

The book "Our Stolen Future," the first Japanese edition of which was published in 1997, aroused strong interest of people in the "endocrine disruptors," which is also referred to as "hormonally active agents." Reports were made on male wild animals becoming feminized or female animals virilized, which probably gave many people a cause for anxiety about the possible effects on human beings. As a result of large-scale investigation and research conducted by the government and other entities afterwards, it has been revealed that there are not very many substances that clearly have endocrine disrupting activity at the concentrations in which they exist in the environment, or cases that endocrine disruption has actually occurred in the environment. For this reason, the endocrine disrupter issues are regarded by many to have completely subsided.
Under such circumstances, the Water Quality Research Team of PWRI has continued to conduct research on the actual conditions of endocrine disrupters in water environment and their biological influences. As a result of this research, we obtained the following results:
• Of the endocrine disrupters existing in rivers, what are considered to have significant biological effects are two substances called estrone and 17β-estradiol, which are female hormones discharged by humans and animals.
• In urban rivers, the substances originate mainly from sewage treatment plants.
• When the concentration of these substances becomes high in river water, yolk precursor proteins, which are supposed to be expressed only in female, are generated in the body of male fish.
Accordingly, to prevent endocrine disrupting effects on aquatic organisms in rivers, it is necessary to use more advanced sewage treatment to maintain the concentration of estrone and 17β-estradiol in the treated sewage water and rivers at a level that does not cause adverse effects. We are conducting further research to propose sewage treatment methods that provide a comfortable environment for living creatures that inhabit rivers.

(Contact: Water Quality Research Team)