The history of the structure made by Porto land cement has been the main material supporting the society and culture for approximately 100 years in the 20th century. A concrete structure is also the property, which should constitute infrastructure and should be simultaneously taken over to the 21st century. Safety and durability are searched for from disturbance, such as an earthquake and a typhoon, and resources, environment, and energy also need to be considered.

Meanwhile, the high flow concrete, which searched for the mobility of the raw contest itself greatly, has also been developed. Especially - Professor, Tokyo University faculty-of-technology Okamura -- the announcement of "high performance concrete" talked much as "he cancels hard toil work called concrete placement which used the vibrator in the conventional placing work" by mass communications PR in the past. There was also time treated as if adhesion aid agent system quantity flow concrete was the omnipotent concrete of self-filling type.

Furthermore, it is also announced from each cement maker or an additive agent maker such as:

Although we are concrete vibrator makers, as long as the sufficient intensity and the sufficient durability for the concrete are guaranteed, we do not advocate an objection to this.

Today, Japanese concrete engineering meeting recognizes that high flow concrete is a concrete improved its mobility remarkably while not spoiling the material separation resistance at the time of freshness with high flow concrete. And the concrete industry today is divided in the two directions to attain the performance:

Although our company thinks it glad that new raw concrete is developed, it expresses big anxiety for adding a lot of organic matters as an additive agent to the concrete realized as a mixture of minerals material under management of people originally. Also in the durability of Tokyo bay Aqua Line which used raw concrete of a common type with which quality and construction were managed more than enough, and was completed as a structure object through sufficient care of curing by water pool etc., it is the level said that "100 years will probably be OK".

Carrying out mixed composition except minerals material, although immediate mobility is searched for therefore does not have an actual result in durability yet. From the view point of a member engaged in the construction which should be taken over to future generations, we think that it is too much irresponsible that saying "do not care after 30 years if it is no problem now". In other words, we think that the design of the design priority, which cannot perform concrete placement firmly, should not be made. High flow concrete cannot be omnipotent concrete. It should be limited to use in the place that has to be made complicate form and needs self-filling. When you build a your company building, does the high flow concrete in which the durable actual result is not shown build?

Also at a concrete secondary product factory, from the request of a work environmental improvement, many experiments of high flow concrete are conducted and combination with rocking style placing equipment (it is vibrator) like seesaw may also be seen.(Why a rocking style? The high flow concrete of the type of the above 1 is raw concrete with which vibration is not effective.)

However, the soft concrete mix is different from conventional concrete mix regarded as the Bingham approximate object. When pour such a soft concrete mix into a mold, which may carries out a leak, there is also no reason that an acceptable product is produced. If high flow concrete is tried, the trial must begin from the mold, which wove side pressure into the design element, and then verification without a vibration truly needed should be made. The key in this field is in a combination design, a mold, and the placing method.

One of the company ideas of ours is becoming the No.1 specialist of the world in the field of vibration. It does not become precocious, although we stood on the role of a world, if a concrete structure good as a result was not produced. With the sole agent, the renting business company, the concrete secondary product factory, and all the users, we wish to help making good concrete.