1.1 Background and purpose

1.1 研究背景與目的

Japanese prefabricated housing manufacturers are unlike any others in the world; they were founded a half century ago, and now supply over ten thousand houses a year. They developed unique building systems between the end of 1950s and early 1960s despite the fact that there was no existing precedent for this type of housing in the Japanese housing market; their building systems have continued to grow until this day. Each company's history does not adequately describe the early developments of building systems because the company's history was not always focused on these developments, although some company histories may partially deal with them. Furthermore, investigating the details of the early developments through interviews with engineers who were in charge of them will become even more difficult in the future.

日本預(yù)制房屋制造商與眾不同;他們是半個(gè)世紀(jì)前建立的，現(xiàn)在每年供應(yīng)一萬(wàn)多套房子。他們?cè)?0世紀(jì)50年代末到60年代初開(kāi)發(fā)了獨(dú)特的建筑系統(tǒng)，盡管在日本的房地產(chǎn)市場(chǎng)上沒(méi)有這種類型的住宅的先例;他們的建筑系統(tǒng)一直在發(fā)展，直到今天。每個(gè)公司的歷史并不能充分地描述建筑系統(tǒng)的早期發(fā)展，因?yàn)楣镜臍v史并不總是集中在這些發(fā)展上，盡管一些公司的歷史可能會(huì)部分地處理它們。此外，通過(guò)對(duì)負(fù)責(zé)早期開(kāi)發(fā)的工程師的采訪來(lái)調(diào)查早期開(kāi)發(fā)的細(xì)節(jié)在將來(lái)會(huì)變得更加困難。

In this circumstance, this study aims to clarify how Japanese prefabricated housing manufacturers developed their housing products in the early stages of the housing business and what the benefits of their approaches were. To verify these points, we extensively interview the engineers in charge of the early developments and examine their company histories, the drawings of early developments, and the existing housing examples.

在這種情況下，本研究的目的是澄清日本預(yù)制房屋制造商如何發(fā)展他們的住房產(chǎn)品在住房業(yè)務(wù)的早期階段，以及他們的方法的好處是什么。為了驗(yàn)證這些觀點(diǎn)，我們廣泛地采訪了負(fù)責(zé)早期開(kāi)發(fā)的工程師，并研究了他們的公司歷史、早期開(kāi)發(fā)的圖紙和現(xiàn)有的住宅實(shí)例。

1.2 Survey targets

1.2調(diào)查的目標(biāo)

The survey targets of this study are 9 major prefabricated housing manufacturers in Japan. Table 1 shows their names and early housing products. In this study, we refer to the period of developing and selling these housing products as the early stage of the housing business for each manufacturer.

本研究的調(diào)查對(duì)象為日本9家主要的預(yù)制房屋制造商。表1顯示了它們的名稱和早期住房產(chǎn)品。在本研究中，我們將每個(gè)制造商開(kāi)發(fā)和銷售這些住房產(chǎn)品的時(shí)期稱為住房業(yè)務(wù)的早期階段。

2 Preceding studies and context of this study

2 本研究的研究背景

Fundamentally, the company histories and founder's biographies of major prefabricated housing manufacturers refer to the developments in the early stages of their operations in the housing business. However, these histories and biographies do not focus on the building systems and the personal ideas and experiences of the engineers in charge of their early developments, who played an important role in developing the early building systems through working as part of a small team in a short timeframe. Nevertheless, there are 3 important preceding studies related to this study. A representative study of building systems developed by Japanese prefabricated housing manufacturers from the 1960s to 1970s is included in the AIJ (Architectural Institute of Japan)'s book.1 This book explains the progress of prefabricated houses in Japan and illustrates details of representative building systems. On the other hand, Togo's and Matsumura's studies examine the emergence of the prefabricated housing industry in Japan and the technical differences in the early building systems through a review of changes in Japanese prefabricated houses.

基本上，主要預(yù)制房屋制造商的公司歷史和創(chuàng)始人傳記指的是他們?cè)诜课輼I(yè)務(wù)早期階段的發(fā)展。然而，這些歷史和傳記并不關(guān)注建筑系統(tǒng)，也不關(guān)注負(fù)責(zé)早期開(kāi)發(fā)的工程師的個(gè)人想法和經(jīng)驗(yàn)，這些工程師通過(guò)在短時(shí)間內(nèi)作為一個(gè)小團(tuán)隊(duì)的一部分工作，在開(kāi)發(fā)早期建筑系統(tǒng)方面發(fā)揮了重要作用。然而，與本研究相關(guān)的重要前期研究有3項(xiàng)。日本預(yù)制房屋制造商在20世紀(jì)60年代到70年代開(kāi)發(fā)的建筑系統(tǒng)的代表性研究被收錄在AIJ(日本建筑學(xué)會(huì))的書(shū)中。這本書(shū)解釋了預(yù)制房屋在日本的發(fā)展，并舉例說(shuō)明了具有代表性的建筑系統(tǒng)的細(xì)節(jié)。另一方面，多哥和松村的研究通過(guò)回顧日本預(yù)制房屋的變化，考察了日本預(yù)制房屋行業(yè)的出現(xiàn)以及早期建筑系統(tǒng)的技術(shù)差異。

3 Features of early development

3 早期發(fā)展特征

3.2 Influence from other cases and persons

3.2 其他案件和人員的影響

Prefabricated houses in the early days were developed with few reference structures. Under this situation, prefabricated housing development was influenced by precedent cases published in documents, by architects and by research conducted outside the company.

在早期，預(yù)制房屋的發(fā)展幾乎沒(méi)有參考結(jié)構(gòu)。在這種情況下，預(yù)制房屋的開(kāi)發(fā)受到文件中公布的先例、建筑師和公司外部進(jìn)行的研究的影響。

3.3 Relationship between organizations

3.3 組織間的關(guān)系

A close relationship between companies was also seen in the early stages of the development of prefabricated houses. In the case of steel structure houses, the staffs of Daiwa House Industry Company took a leading role in the development of prefabricated houses in the Toshiba Housing Industry and in the development of Kubota House (later renamed Sanyo Homes). This relationship was manifested in the situation in which the umbrella company of the former company was in charge of selling the Daiwa Midget House and in which the structure system that the latter company adopted was quite similar to that of Daiwa House. Sekisui House, which became independent from Sekisui Chemical Company, accepted staffs of the company for employee trainings in developing Sekisui Heim M1. Sekisui House advised Asahi Chemical Industry Company, which has the same corporate origin as Sekisui House, to shift from an agency selling system to a direct selling system.

在預(yù)制房屋發(fā)展的早期階段，公司之間的關(guān)系也很密切。在鋼結(jié)構(gòu)房屋方面，大和房業(yè)公司的員工在東芝住宅行業(yè)的預(yù)制房屋開(kāi)發(fā)和久保田住宅(后來(lái)改名為三洋住宅)的開(kāi)發(fā)中發(fā)揮了主導(dǎo)作用。這種關(guān)系表現(xiàn)在前一個(gè)公司的母公司負(fù)責(zé)銷售大和小賣(mài)部，后一個(gè)公司采用的結(jié)構(gòu)體系與大和小賣(mài)部非常相似。Sekisui House從Sekisui Chemical Company中獨(dú)立出來(lái)，在開(kāi)發(fā)Sekisui Heim M1時(shí)，接受了公司員工的培訓(xùn)。Sekisui House建議Asahi Chemical Industry Company(與Sekisui House有相同的企業(yè)淵源)從代理銷售系統(tǒng)轉(zhuǎn)向直銷系統(tǒng)。

In the case of wooden structural houses, as the original companies in the industry, Eidai Company and Misawa Homes Company had influences on the others. The influence of Eidai Company was significant, particularly to local builders, because the company established a franchise system covering 1200 builders  in the1970's. Additionally, in 1978, the company had a wide influence on the industry when most of its engineering staff moved to Mitsui Home and other companies after the company filed bankruptcy. Misawa Home helped a certain number of housing organizations to mature, including some leading‐edge suppliers of conventional wooden houses and prefabricated housing companies, such as SxL, which used to be one of its agents.

以木結(jié)構(gòu)房屋為例，Eidai公司和Misawa Homes公司作為行業(yè)中最早的公司，對(duì)其他公司產(chǎn)生了影響。Eidai公司的影響是巨大的，特別是對(duì)當(dāng)?shù)氐慕ㄖ?，因?yàn)樵摴驹?0世紀(jì)70年代建立了一個(gè)覆蓋1200個(gè)建筑商的特許經(jīng)營(yíng)系統(tǒng)。此外，在1978年，該公司對(duì)行業(yè)產(chǎn)生了廣泛的影響，當(dāng)時(shí)該公司的大部分工程人員在公司破產(chǎn)后搬到了三井住家和其他公司。三澤之家?guī)椭艘欢〝?shù)量的房屋組織走向成熟，包括一些傳統(tǒng)木結(jié)構(gòu)房屋的領(lǐng)先供應(yīng)商和預(yù)制房屋公司，如曾是其代理商之一的SxL。

3.4 Organization and duration of development

3.4 組織機(jī)構(gòu)和開(kāi)發(fā)期限

Some engineers stated that the development organization was small and the duration of the development time was short in the early days compared to the situation today. For example, the Daiwa Midget House was developed in 1 month by the one engineer in charge. The development team of Sekisui House Model A was composed of two almost new recruits and, according to the business diary at that time, they performed a wide range of functions, including the study of weathering details, structural analysis, meetings with constructors, a quantity survey and process planning.

一些工程師表示，與今天的情況相比，早期的開(kāi)發(fā)組織很小，開(kāi)發(fā)時(shí)間持續(xù)時(shí)間很短。例如，大和小房子是由一個(gè)負(fù)責(zé)的工程師在一個(gè)月內(nèi)開(kāi)發(fā)的。Sekisui House Model A的開(kāi)發(fā)團(tuán)隊(duì)由兩名幾乎是新招募的人員組成，根據(jù)當(dāng)時(shí)的業(yè)務(wù)日志，他們執(zhí)行了廣泛的功能，包括氣候細(xì)節(jié)的研究、結(jié)構(gòu)分析、與施工人員的會(huì)議、數(shù)量調(diào)查和工藝規(guī)劃。

The development process of the National House Industrial Company was unique, as the company allowed 3 teams to compete for the project. The company made no less than 5 test products a year for Matsushita Type‐One. Table 2 shows the development organization of each company in the early days. Eidai Company and SxL are omitted in the table because the interview with them was not available.

國(guó)家住宅工業(yè)公司的發(fā)展過(guò)程是獨(dú)特的，該公司允許3個(gè)團(tuán)隊(duì)競(jìng)爭(zhēng)該項(xiàng)目。該公司每年為松下制造不少于5個(gè)測(cè)試產(chǎn)品。表2顯示了每個(gè)公司早期的開(kāi)發(fā)組織。表中省略了Eidai公司和SxL，因?yàn)闊o(wú)法對(duì)他們進(jìn)行采訪。

4.1 Structural system

4.1 結(jié)構(gòu)體系

The major theme of early prefabricated house development was the structural system and the building system of some products were totally revised in the early stages of the development.

早期預(yù)制房屋開(kāi)發(fā)的主要主題是結(jié)構(gòu)體系，一些產(chǎn)品的建造體系在開(kāi)發(fā)的早期就進(jìn)行了全面的修改。

Daiwa house tried to develop the building system of the Midget house (1959), which is less than 10 sqm and was designed as an additional children's room; the Super Midget house (1960) design just included the addition of a kitchen and a toilet. However, the Daiwa House Type‐A adopted different building systems than the Midget house. For example, the length of the span of the roof panel was limited because the panels were on ridge beams and girders and if the ridge direction is extended, columns would have to be placed inside the rooms. Therefore, the Daiwa house adopted a king post and then attached a panel truss arrangement to form a roof truss (Figure 2, left). Regarding the exterior wall structure, panels of the Midget house were put into two light gauge channel steel back‐to‐back columns between which the Daiwa House Type‐A connectors (C‐shape, almost square) are inserted (Figure 2, right).

大和試圖開(kāi)發(fā)小房子的建筑系統(tǒng)(1959年)，它不足10平方米，被設(shè)計(jì)成一個(gè)額外的兒童房間;超級(jí)小房子(1960年)的設(shè)計(jì)只是增加了一個(gè)廚房和一個(gè)廁所。然而，大和房型A采用了不同于小房子的建筑系統(tǒng)。例如，屋頂板的跨度是有限的，因?yàn)榘迨窃谖萘汉痛罅荷希绻萘旱姆较虮谎娱L(zhǎng)，柱子就必須放在房間里。因此，大和房舍采用了一根主梁，然后附加了一個(gè)板桁架布置，形成了一個(gè)屋頂桁架(圖2，左)。關(guān)于外墻結(jié)構(gòu)，迷你屋的面板被放入兩個(gè)輕型槽鋼背靠背的柱子中，其中插入了大和房型A連接器(C形，幾乎是方形)(圖2，右)。

The structural systems of the 9 companies are roughly divided into steel framework and timber panel construction. Every company was conscious of the differences in the building systems of the other companies. Furthermore, some of the original structural systems that were developed earlier are still maintained today.

這9家公司的結(jié)構(gòu)體系大致分為鋼框架和木板結(jié)構(gòu)。每個(gè)公司都意識(shí)到其他公司建筑系統(tǒng)的不同。此外，一些早期開(kāi)發(fā)的原始結(jié)構(gòu)系統(tǒng)今天仍然保留著。

Three steel framework companies (Daiwa House Industry Company, Sekisui House, National House industrial Company) developed their original system by taking the other companies’ structural system into account: the Sekisui House system is a steel framework arrangement with interior and exterior wall panels attached on site; in Daiwa House Industry's design system, the interior and exterior wall panels are finished in their factory and constructed on site; and the National House Industrial company's system design consists of a lightweight steel rigid frame. In these 3 companies, those differences in the framework structure are maintained in their current main products. Moreover, as Daiwa House Industry installed exterior walls on site, some other companies temporarily used a similar type of construction in some of their housing products. In timber panel construction, although the company recognized that its functionality was not good, the Misawa Homes Company continued to use the double‐sided panel since the double‐sided panel can prevent warpage after construction and to differentiate this company from other companies, such as the Eidai Company, which had adopted single sided panels.

三家鋼結(jié)構(gòu)公司(大和房業(yè)公司、積水住宅、國(guó)民住宅工業(yè)公司)結(jié)合其他公司的結(jié)構(gòu)體系，開(kāi)發(fā)了自己的原始系統(tǒng):積水住宅系統(tǒng)是一種鋼結(jié)構(gòu)布置，內(nèi)部和外部墻板都在現(xiàn)場(chǎng);在大和房屋的設(shè)計(jì)體系中，室內(nèi)外墻板都是在他們的工廠內(nèi)完成，并在工地施工;國(guó)家住宅工業(yè)公司的系統(tǒng)設(shè)計(jì)由輕量化鋼剛架組成。在這三家公司中，這些框架結(jié)構(gòu)上的差異保留在他們當(dāng)前的主要產(chǎn)品中。此外，由于大和房屋在現(xiàn)場(chǎng)安裝了外墻，其他一些公司暫時(shí)在他們的一些住房產(chǎn)品中使用了類似的建筑類型。在木材面板施工,盡管該公司意識(shí)到,它的功能是不好,三澤住宅公司繼續(xù)使用雙面面板，因?yàn)殡p面面板可以防止翹曲，而且建設(shè)和區(qū)分本公司和其他公司,比如Eidai公司采取了單面的面板。

The features of these structural systems have been maintained until recently because each company continued development with the awareness of its differentiation from other companies and because their production facilities and sales methods had been adapted to the products that were developed early .

這些結(jié)構(gòu)系統(tǒng)的特征一直保持到最近，因?yàn)槊總€(gè)公司都意識(shí)到自己與其他公司的不同，并在不斷發(fā)展，因?yàn)樗麄兊纳a(chǎn)設(shè)施和銷售方法已經(jīng)適應(yīng)了早期開(kāi)發(fā)的產(chǎn)品。

4.2 Module

4.2 模數(shù)

4.3 Joint of components

4.3 構(gòu)件連接

The joints of the components were also an important issue in the development. There were many changes in the relatively early stages of development because of the workability and strength of the joints.

零件的接頭也是研制過(guò)程中的一個(gè)重要問(wèn)題。由于關(guān)節(jié)的可操作性和強(qiáng)度，在發(fā)展的相對(duì)早期階段發(fā)生了許多變化。

Regarding workability, Sekisui House originally manually punched a bolt hole and changed to press processing due to large position error. Daiwa House Type‐A used a steel cover plate at the panel joint because of waterproofing and an error adjustment that was due to constructing their factory finished panels at sites, as mentioned above. The attachment of their panel joints was changed for design reasons to a wet sealing method in 1975 and changed to a method using dry gaskets in 1981.

在可加工性方面，積水原本是手工打孔，由于位置誤差較大，所以改成了沖壓加工。大和房型‐A在面板連接處使用了鋼蓋板，用于防水和誤差調(diào)整，這是基于在工地上建造他們的工廠成品板，如上所述。由于設(shè)計(jì)原因，他們的面板連接在1975年改為濕密封方法，并在1981年改為使用干墊圈。

Regarding the strength of the joints, the Sekisui Heim M1 model adopted a rigid frame structure and used bolt joints until their second prototype was developed (May 1970). However, with the introduction of the third prototype, the structure was changed to weld joints because of the weakness of the framework joints. In the development of the rigid frame of the National House Industrial Company, spring lock washers were used to prevent the joint bolts becoming loose (Figure 5). An automobile factory was the source of a clue to the engineer. When the Misawa Homes Company acquired approval by the Housing Loan Corporation in 1966 (the regulation started in 1964), the strength of the adhesive on site construction was not approved. Therefore, in order to obtain the strength by using only nails, they increased the width of the frame members from 18 mm to 30 mm.

在關(guān)節(jié)強(qiáng)度方面，積水 M1模型采用了剛性框架結(jié)構(gòu)，并使用了螺栓連接，直到他們的第二個(gè)原型被開(kāi)發(fā)出來(lái)(1970年5月)。然而，隨著第三個(gè)原型的引入，由于框架接頭的弱點(diǎn)，結(jié)構(gòu)被改為焊接接頭。在國(guó)家房屋公司的剛架開(kāi)發(fā)過(guò)程中，使用了彈簧鎖墊圈來(lái)防止連接螺栓松動(dòng)(圖5)。當(dāng)三澤住家公司在1966年獲得住房貸款公司的批準(zhǔn)時(shí)(該規(guī)定開(kāi)始于1964年)，現(xiàn)場(chǎng)施工粘接劑的強(qiáng)度沒(méi)有得到批準(zhǔn)。因此，為了獲得強(qiáng)度只使用釘子，他們?cè)黾恿丝蚣艹蓡T的寬度從18毫米到30毫米。

5 Conclusion

5 結(jié)論

This study has conducted interviews with engineers that developed the building systems of 9 major prefabricated housing manufacturers during the early stage of the prefabricated housing business and examined each company's history and their drawings associated with their early development. In conclusion, the following has been clarified.

本研究訪問(wèn)了在預(yù)制裝配式房屋業(yè)務(wù)早期階段開(kāi)發(fā)了9家主要預(yù)制裝配式房屋制造商的建筑系統(tǒng)的工程師，并檢查了每家公司的歷史及其與早期開(kāi)發(fā)相關(guān)的圖紙。最后，澄清如下。

First, this study has concretely identified the approaches 9 major prefabricated housing manufacturers applied to develop their housing products, the architectural sources that influenced their early developments, the team members that participated in the development and the timeframe associated with the development. Each manufacturer's approach for the development of prefabricated houses was different from that of the other manufacturers because the approach depended on each manufacturer's business field and the available technology. Although the prefabricated housing manufacturers started their early developments of housing products to make effective use of their new materials and the company's skills, some of them eventually transitioned out of these first manufacturing objectives. Basically, each of the 9 major prefabricated housing manufacturers developed their early housing products by use of a small team in a short‐term timeframe, while obtaining cooperation or advice from architects, researchers of universities and other prefabricated housing manufacturers. At the same time, some housing developments strongly depended on the personal experience and knowledge of engineers in charge of the project.

首先，本研究具體確定了9家主要預(yù)制房屋制造商開(kāi)發(fā)其住房產(chǎn)品的方法、影響其早期開(kāi)發(fā)的建筑來(lái)源、參與開(kāi)發(fā)的團(tuán)隊(duì)成員以及與開(kāi)發(fā)相關(guān)的時(shí)間框架。每個(gè)制造商發(fā)展預(yù)制房屋的方法與其他制造商不同，因?yàn)檫@種方法依賴于每個(gè)制造商的業(yè)務(wù)領(lǐng)域和現(xiàn)有的技術(shù)。雖然預(yù)制房屋制造商開(kāi)始他們的早期開(kāi)發(fā)住房產(chǎn)品，以有效利用他們的新材料和公司的技能，他們中的一些最終過(guò)渡出這些最初的制造目標(biāo)?；旧?，9家主要的裝配式房屋制造商都是在短期內(nèi)通過(guò)一個(gè)小團(tuán)隊(duì)開(kāi)發(fā)了他們?cè)缙诘淖》慨a(chǎn)品，同時(shí)獲得了建筑師、大學(xué)研究人員和其他裝配式房屋制造商的合作或建議。與此同時(shí)，一些住宅開(kāi)發(fā)項(xiàng)目強(qiáng)烈地依賴于項(xiàng)目負(fù)責(zé)人的個(gè)人經(jīng)驗(yàn)和知識(shí)。

Second, the prefabricated housing manufacturers immediately changed a remarkable exterior design of their early housing products, the so‐called Prefab style, into the ordinary one.This was related to the modification of their building systems; the unique structural components that was used in systems, such as the Sekisui House Model A or the Midget house, was changed into a post and beam construction system of light gauge steel, and the unique module size, such as 800 or 1260 mm, was changed to one of approximately 900 mm, similar to the Japanese conventional module size. In addition, some of the manufactures changed their sales organization from an agency system to a direct sales system in the early stage of housing business. Although these important changes of structural system, planning module size and sales system occurred immediately, some of the steel building systems established by 3 pioneer companies in their early business stage became not only a key point of differentiation from the competitive housing products but also a basis of their sales and production systems and remain so to this day.

其次，預(yù)制房屋制造商立即改變了他們?cè)缙诜课莓a(chǎn)品的一個(gè)顯著的外觀設(shè)計(jì)，所謂的預(yù)制風(fēng)格，變成了普通的。這與他們的建筑系統(tǒng)的修改有關(guān);獨(dú)特的結(jié)構(gòu)組件,用于系統(tǒng),如Sekisui房子模型或小型的房子,變成了一個(gè)輕量鋼梁柱結(jié)構(gòu)系統(tǒng),和獨(dú)特的模塊大小,例如800或1260毫米,改變了一個(gè)大約900毫米,類似于日本傳統(tǒng)模塊大小。另外，在住房業(yè)務(wù)發(fā)展的初期，一些廠家將銷售組織從代理體系轉(zhuǎn)變?yōu)橹变N體系。雖然這些重要的變化的結(jié)構(gòu)體系、規(guī)劃模塊大小和銷售系統(tǒng)立即發(fā)生,一些鋼建筑系統(tǒng)建立了3先鋒公司不僅在他們?cè)缙诘纳虡I(yè)舞臺(tái)成為一個(gè)關(guān)鍵的差異化競(jìng)爭(zhēng)的房地產(chǎn)產(chǎn)品,而且還能根據(jù)他們的銷售和生產(chǎn)系統(tǒng),直到今天依然如此。

Disclosure

作者特別感謝JSPS KAKENHI撥款編號(hào)22656128的資金來(lái)源，以及所有受訪者和支持這項(xiàng)研究的人。

The authors have no conflict of interest to declare.