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Technologies used in Japan for constructing underground stations for heavy-rail urban rapid transit systems are described. Two example projects have been chosen that illustrate different approaches which incorporate several advanced engineering features. These examples illustrate the top-down, or reverse construction method, secant-pile walls, and underground mining of stations in soft ground. With higher direct costs and longer durations, the methods discussed here will not offer solutions to all U.S. station construction projects. Nevertheless, there is a lot to be learned from the Japanese about working on congested sites in urban areas, particularly under the tough geotechnical conditions in Japan. Considering total costs, including disruptions to commerce and traffic in urban areas, the bad publicity, loss of citizen and political support, litigation and other factors that are increasingly encroaching on United States construction methods, it is argued that Japanese construction methods might provide attractive alternatives.

In-house research by private companies is fundamental to the technological advancement of the Japanese construction industry. Shortly after World War II several of the largest construction companies established research institutes. These institutes have since grown and become an integral part of Japanese construction. Many have laboratories with highly educated professional research staffs working with large-scale and technologically complex research equipment that makes them among the best construction research facilities in the world. This research transcends all disciplines related to construction and a large fraction is similar to the fundamental and applied research one finds in U.S. universities. This research enjoys strong top-management support and the research institutes are recognized as important resources by the operations personnel in the companies. Benefits and incentives include creation of new markets, solving practical field problems, corporate prestige, gaining a keener competitive edge, substantiating claims, proving compliance with regulations, and advancing Japan to the forefront of world construction technology.

This paper summarizes results of a policy-level workshop attended by a distinguished group of construction people representing owner, contractors, government, and educators. The April 1975 workshop was funded by the National Science Foundation and was sponsored by the Construction Institute at Stanford University. These industry leaders spent two full days in frank, far-reaching analyses in an attempt to define basic problems that the industry will face in the years ahead. In specific terms, the workshop was designed to identify basic research needs in the management of construction and define and formulate goals for basic research in this area. The participants' efforts were concentrated in four general subject areas, including: (1)Manpower and organizational development; (2)management methodologies; (3)innovations in construction methods; and (4) construction industry dynamics. The paper also explains the role of basic research in construction, and suggests guidelines for its implementation and funding.

Components of the industry that are described include public works agencies, trade and professional associations, approximately half a million contractors, private owners, banking, and trading groups. Other sections of the paper give more detail on ranking and prequalification of contractors by public and private owners, selection of bidders, factors affecting project design and construction, project management, specialty contractors, and methods and techniques for project control. Although many factors would ease acceptance of Professional Construction Management approach, three potential obstacles include: (1)Closer interdependencies between general contractors and their subcontractors; (2)ambiguities in contract administration related to Confucian sense of social obligation; and (3)legal restrictions presenting commencement of projects before all plans and specifications have been completed and approved by building officials. Nevertheless, there is strong interest in adapting this method to Japanese conditions.

This paper outlines basic principles for estimating and controlling field labor costs on construction projects. It divides labor costs into two main categories. The first deals with the strictly financial aspects. These include basic wages, fringe benefits, insurance, taxes, and wage premiums. Most of these are readily quantifiable. The second category introduces factors related to productivity. These include regional variations in skill and work rules; environmental effects ranging from weather and topography to the immediate working conditions of individual craftsmen; learning curve relationships; project work schedule; and interrelationships of labor and management. Productivity factors are difficult to quantify and require much experience and judgment to do so. However, they also offer the contractor the greatest opportunity for control. In both the financial and productivity categories, several of the more subtle cost implications of the various factors are explained. Brief precautionary reference is also made to the many published sources of labor cost data.

The 5.5m diameter Seikan Tunnel in Japan will extend 54 kilometers, crossing under the Tsugaru Straits. When completed the –2 billion tunnel will be the longest in the world, and will carry both standard-gauge rail traffic as well as the 260 km/hr Shinkansen passenger express trains. To construct this tunnel, however, it has been necessary to go through extremely difficult geologic conditions, including about a dozen major faults, volcanic strata, and areas with water bearing formations transmitting up to the full 250-meter hydrostatic head from the sea above. The main construction procedures are outlined, including excavation of a pilot bore and service bore as well as the main tunnel. Long horizontal exploratory drilling has been employed, and excavation itself is preceded by extensive chemical grouting.

Both improved methods and better application of existing principles are needed in the planning and control of engineering and construction projects. Using an analogy and a model, this paper explains the basic concepts in the information feedback-control process used on well-managed projects. The objective is to provide a broad perspective against which to reference specific subsystems such as planning and scheduling, cost engineering, materials procurement and tracking, quality control, and so forth. The paper then amplifies several key components of the feedback-control mode, including means for measuring and controlling progress; methods for information processing; requirements for effective reporting; and guidelines for taking corrective action.

This paper describes a project designated to develop, test, implement and document a practical, low-cost, terminal and microcomputer-based interactive simulation and graphics systems and related courseware to serve as a teaching laboratory. This research will bring together essential work from three important fields: (1)Time-lapse photographic documentation of unit operations; (2)computer-based simulation modeling; and (3)interactive man-computer graphics. The purpose is to create a system for statistical documentation of discrete unit operations, transfer and reduction of data by directly synchronizing the time-lapse film with the real-time computer system, and analysis via simulation modeling and interactive man-computer graphics. By combining these three technologies, a system is obtained whose analytical power far exceeds the sum of its parts.

This paper describes an in-depth research study to evaluate the current and projected state of productivity in the construction of transportation facilities and explores improved mechanisms for implementing transportation construction innovations. At this stage it is evident that some of the major obstacles that impact costs, reduce productivity, and inhibit the implementation of innovations result from:(1)Decisions made and policies set during the planning and design phases; (2)the contractual and organizational structure chosen for project administration; and (3)delays and cost increases resulting from third-party intervention. There are also opportunities for further improvements through wider and more effective use by construction contractors of management techniques that have already proven to be successful.

This paper describes interrelationships between engineering design, construction, and operation costs for a facility, and shows how the level of influence over those costs decreases precipitously as the project evolves. The level of influence is by far the greatest during engineering and design, while actual expenditures at that stage are relatively small. The level of influence concept can be helpful in forming contractual arrangements that minimize the suboptimization of costs for one party at the expense of overall project costs and benefits. Contractual arrangements should be drawn so as to assure that current construction and operations knowledge will be injected in the design process. Construction Management and design-construct, if appropriately tailored to the needs of a particular situation, can be helpful for this purpose. A second important conclusion is that efforts to suboptimize design costs by requiring competitive bidding for professional services are likely to produce much higher project costs in the long run.

The Tokyokou Dainikoro Tube-Tunnel is a four-lane highway tunnel which, when completed in 1980, will provide direct access to manmade islands in the Bay. The estimated cost is about 30 billion yen ($130,000,000). The overall project length is 1,782 m (5,847 ft), of which 744 m (2,441 ft) between two ventilation buildings is the submerged tube-tunnel, consisting of six section each 124m (407 ft) long. Approaches and ventilation buildings are contructed on deep-pile foundations, while the tube sections are placed in a dredged trench that is later backfilled. Interesting methods described include: (1)Construction of tubes from reinforced concrete rather than fabricated steel. (2)construction in a dry dock that was subsequently flooded: (3)a two-point temporary landing on adjustable jacks rather than on a precisely leveld bedding: and (4)subsequent pumped backfill with bentonite mortar grout under the tubes.

ESSENTIAL LOGICAL DETAILS ARE EXPLAINED FOR A PROCEDURE THAT INTEGRATES TWO IMPORTANT NETWORK-BASED PROJECT MANAGEMENT TECHNIQUES: (1) RESOURCE ALLOCATION; AND (2) TIME-COST TRADE-OFF ANALYSIS. IN THE RESEARCH PROJECT UPON WHICH THE PAPER IS BASED, THESE TECHNIQUES WERE ALSO INTEGRATED WITH BASIC CRITICAL PATH NETWORKING, RESOURCE LEVELING, AND CASH FLOW ANALYSIS. ALL WERE DEVELOPED IN THE CONTEXT OF AN INTERACTIVE MAN-COMPUTER SYSTEM. THE PROEDURE RETAINS PROPERTIES OF NETWORKS ANALOGOUS TO THE "CRITICAL PATH" AND "FLOAT" WHILE OPERATING WITHIN RESOURCE CONSTRAINTS. A NEW "INTERVAL APPROACH" TO TIME-COST TRADE-OFF ANALYSIS ALSO OVERCOMES MANY THEORETICAL AND PRACTICAL PROBLEMS OF EARLIER OPTIMIZATION TECHNIQUES. HUMAN INPUT FORMS AN INTEGRAL PART OF THE SYSTEM AS A SOURCE OF MANAGEMENT INSIGHT, JUDGEMENT, INTUITION, QUALITATIVE ANALYSIS, AND PRACTICAL EVALUATION. A STEP-BY-STEP EXAMPLE ILLUSTRATES THE BASIC CONCEPTS. /ASCE/

An interactive man-computer system for project planning and scheduling can overcome many of the theoretical and practical problems of manual and computer batch processing methods. Four key elements in the proposed unified system include: (1) a man, or group of men; (2) a man-computer interface; (3) an integrated system of interactive programs; and (4) a direct access computer data base. The man is the source of insight, judgement, intuition, qualitative analysis, and practical evaluations. The interface is a subsystem of devices and programs that allows a nonspecialist to converse with the computer at the application problem level. The programs logically integrate the principles behind basic network methods including critical path scheduling, resource allocation and leveling, time-cost analysis, and cash flow. The data base maintains files of information relating to project planning and scheduling in a readily accessible form.