Building Standard Law Research Articles

Performance-Based Provisions For Fire Safety In The Japanese Building Standard Law: How To Connect Regulation And Engineering

In Japan, a performance-based code has been added to the existing Building Standard Law (BSL), rather than making a new Law. Before the revision, performance-based design had been done under the “equivalency” concept. Today, the law itself has been transformed to allow performance-based design. The revision is a result of requests from the legal sector that the Law, rather than the Government, should set standards to rule. As a result, government discretion has become more limited. In order to preserve continuity from the past, the current BSL includes both conventional prescriptive clauses as well as performance-based ones in the evacuation and fire resistant structure sections. The most important point is to clarify the objectives of regulation and their performance criteria. To avoid disturbance of technological development, definite requirements in the BSL and the Enforcement Order have been limited only to functional expressions. To allow efficient implementation, the government has set standard verification methods, new plan review routes and executive bodies. The strategy of verification of fire safety is that each value of prescriptive requirement transfers to the time that is calculated, and performance is required for not only each components of building and their testing method, but also for a unit of the whole floor, or the whole building.

改正建築基準法の解放工学的基盤波を想定した表層地盤増幅特性の簡便評価法

We proposed a simplified method to evaluate strong ground motions response spectra at ground surface considering the inelastic amplification characteristics of surface layers. We assume that input motions on the engineering bedrock are given by the reviesed Enforcement Order of the Building Standard Law of Japaa This method is far simple and easy to calculate compared to the limit strength method in the revised Building Standard Law of Japan, because this method requires only the 30m depth soil layer data from the surface and substitution from these data to several equations. Despite of simplicity, this method predicts the results of equivalent elastic earthquake response analyses more adequately than the limit strength method in the revised Building Standard Law of Japan.

WIND LOADS ON FREE-STANDING CANOPY ROOFS: A REVIEW

Previous studies of wind loads on free-standing canopy roofs have been surveyed. Focus is on the data obtained from wind-tunnel measurements in simulated atmospheric boundary layers as well as from full-scale measurements. Comparisons are made between these studies for some aerodynamic characteristics, such as mean and peak wind force coefficients. The wind load provisions in the current Building Standard Law of Japan are also compared with the experimental results. The comparisons are restricted to the clear flow case with no obstructions under the roof. A discussion is made of the subjects to be investigated for making the provisions more appropriate.

面材により部分拘束された曲げを受ける薄板軽量リップ溝形鋼のゆがみ座屈挙動

Cold-formed thin-walled steel members with thicknesses of around 1mm are relatively new structural members in Japan. It is because such a thin steel member had not been long allowed to use as a structural member under the Japanese Building Standard Law. This situation has been changed in recent years through the development of steel-framed houses. Although the use of such a thin steel member is currently possible, there are still some design issues to be clarified for realizing the broader applications, mainly related to its complex buckling behavior. The complex buckling is called distortional buckling and is often seen in the floor and roof panels in steel-framed houses. To study the behavior of distortional buckling in detail therefore, negative bending tests were conducted in this paper for panels consisting of two lipped-channels and structural plywood fastened together with screws. Twelve bending tests provided detailed behavioral information on distortional buckling and the possible strength evaluation methods for improving the design of thin-walled steel members.

可燃物のランダム配置による発熱量と煙流動の影響に関する研究

By the revision of the Building Standard Law, to ascertain the evacuation safety performance, the methodology that regards a fire as the phenomenon of combusion that the heat release rate changes every moment was added. The purpose of this paper is to consider the influence of the characteristic of fire load on the heat release rate and smoke movement at the early stage of the fire. First, we estimated the heat release rate and smoke movement in the room where fire started by changing some parameters with the model that considered the random distribution of fire load, and inspected the limited time defined as an indicator of fire safety, that occupants in the room where fire started could safely evacuate. Second, we examined about the limited time by changing smoke exhaust rate in the same way.

Recent developments in seismically isolated buildings in Japan

The Building Standard Law of Japan and related Enforcement Order and Notifications have been substantially revised since the year 2000 to introduce a performance-based regulatory and deregulation system for building control systems. Up to then, time-history analyses were mandatory for isolated buildings and had to be specially approved by the Minster of the Ministry of Construction (MOC). Simplified design procedures based on the equivalent linear method for seismically isolated buildings have been issued as “Notification 2009 — Structural calculation procedure for buildings with seismic isolation” from MOC, and are now integrated into the Ministry of Land, Infrastructure, and Transportation (MLIT). Along with Notification 2009, “Notification 1446 of year 2000 — Standard for specifications and test methods for seismic isolation devices” was also issued. Buildings with heights equal to or less than 60m and that are designed according to these Notifications, including base isolated buildings, only need approval from local building officials, and no longer require the special approval of the Minister of MLIT. This paper summarizes: 1) some statistics related to buildings with seismic isolation completed up to the end of 2001; 2) simplified design procedures required by Notification 2009 of year 2000; and 3) performance of seismic isolation devices required by Notification 1446 of year 2000.

Revised Wind Load Provision in the Building Statutes

This paper describes the revised wind load provision of the Building Statutes. The Building Standard Law that is the fundamental one in the Building Statutes and the basic things including the objective of the Statutes, basic performance requirements on buildings and etc. are prescribed in it. It was revised in 1998 and declared that technical regulations should been prescribed with the performance based forms. Following the revision, the Building Standard Law Enforcement Order and Notifications of Ministry of Construction that form the technical regulations including design load provisions were revised in 2000. Wind load provision was revised along with the other provisions. In this paper, the revised wind load provision is presented as well as the revision works

中低層建築物群周辺の曇天時照度比・天空率と晴天時日射エネルギー比 : 市街地外部空間の日射・採光環境の質を考慮した形態コントロール手法に関する研究(その2)

This paper aims at evaluating sunlight and skylight conditions in a modeled block in low-and-medium-rise residential area. It is turned out that sky factor is the useful index for expressing the brightness under overcast sky. Secondly, we accumulate the calculated impact of buildings on each lot to compute the whole impact of the buildings on open spaces assumed in the Building Standard Law. It is compared with the actual impact of all buildings calculated simultaneously to show that the impact of buildings is underestimated more than three hours in terms of sunshine duration on a north-south street and intersections in the accumulated result.

改正建築基準法 (平成12年改正) に基づく建築材料としてのコンクリートの扱い

平成12年6月, 建築基準法・同施行令が, 主たる条文について仕様規定的内容から性能規定的内容に改められ, 施行された。この改正に伴い, 国土交通省が定めている告示が大幅に見直され, また同省住宅指導課より出されていた課長通達などの通知類が全廃されたため, 建築構造用の主要な材料としてのコンクリートについても, その扱いが大きく変った。本稿は, この様な基準法及び関連基準類の大幅な改正の中身を確認すると共に, 建築基準法における指定建築材料としてのコンクリートの扱いについて, その概要を述べたものである。

Movement of Internationalization in Building Structural Design for Wind Load and New Wind Load Regulations of the Building Code in Japan

The Building Standard Law was revised in June 1998 in Japan. It was the first major revise after it had been established 50 years before. The trigger is said to be an agreement between the President Clinton of USA and a former Prime Minister Hashimoto. They made a promise on reducing the non-tariff barrier. They say that the revise of the Building Standard Law was decided as the result. This is a good example of internationalization of the building code. Since these situations are in actuality, we have to take into consideration of international harmonization when we discuss domestic code problems. However information of international activities does not seem to be widely distributed. In this paper, ISO activities and the relevant APC activities are introduced focussing wind load regulation. The wind load provisions in the revised Building Standard Law Enforcement and the relevant technical regulations are introduced as well as the Housing Performance Indication System in the Housing Quality Assurance Act. The information shearing is expected to have a great help when we proceed into the next step of international harmonization of building code.

附室加圧煙制御システムにおける給気量の手計算方法

While vestibule pressurization smoke control systems are now popularly used in Japan in place of the smoke extraction methods prescribed in the Building Standards Law, it cannot be said that a rational method for determining the air supply rates required for achieving the smoke control goals has been well-established. As a result, computer simulation models are usually used as the means to estimate the air supply rates. It may not be inappropriate but it causes some difficulties for ordinary designers to try this smoke control system. This paper proposes a practical design method of vestibule pressurization smoke control systems. This method comprehensively covers the fire scenarios corresponding to every stage of evacuation, namely fire room evacuation, fire floor evacuation and whole building evacuation. The required rates of air supply are determined to meet all the criteria imposed to verify the safety requirements at these three stages of evacuation. The calculation procedure in this method consists of a set of simple formulas for pressure and opening flow rates developed based on the average pressure difference concept so it can only be followed by the use of a hand calculator. This method is expected to help designers and engineers easily understand what and how to do to rationally and effectively design the smoke control system and to help building officials or whoever may concern with approval of the system know how to check its compliance.

Brief introduction to acoustic standards of the Japanese building standard law(building control law)and the Japanese new labeling system for housings.

Brief introduction to acoustic standards of the Japanese building standard law(building control law)and the Japanese new labeling system for housings.

Wind loading standards and design criteria in Japan

This paper introduces the Building Standard Law of Japan and the BCJ Recommendations for Structural Safety for Wind. Both are official documents published by the government or its agency. It then introduces the AIJ Recommendations for Loads on Buildings and AIJ Guidelines for the Evaluation of Habitability to Building Vibration. These two documents are not official ones, and designers are not bound by them. Finally, the BCJ Guidebook on Wind Tunnel Experiments for Building Engineers is introduced as a manual relevant to wind-resistant design of buildings.

The Japanese Building Standard Law and a series of steels for earthquake-resistant building structures

This contribution refers to the Building Standard Law in Japan and by focusing especially on the part which is related to seismic forces, shows how to protect humans and property (in Japan) from earthquake disasters. In 1981, the Law was amended to introduce plastic design into architecture. In order to enhance the ability of the new seismic proof structural design method, a new series of steels was developed and manufactured in 1994. Material damage induced by repeated earthquakes is investigated in this paper. The newly produced pre-damaged SN490B steel (one of the new steels) is tested and evaluated under dynamic tension. The pre-damage is introduced by pre-fatiguing or pre-straining. Compared with SM490A steel (a conventional steel), the remaining mechanical properties of the SN490B steel resemble those of SM490A even under dynamic tension. However, once plastic deformation has developed in the SN490B steel, it loses the capability of accepting large deformation when used in structural members. Tests suggested that, once the structural building has suffered plastic deformation, the building components will not comply with the new seismic proof design method. In case of such a condition, the components fabricated from these new steels should be either reinforced, replaced or rebuilt.

建築基準法の性能規定化と木材工業への影響

建築基準法の性能規定化と木材工業への影響

A Pilot Case Study of a Performance-Based Fire Safety Design Method to a Multi-Tenant Office Building.

A pilot case study was carried out to examine the feasibility of a performance based fire safety design system to be developed in Japan. This system intends to give more degree of freedom in fire safety design than the method prescribed in current building standards law of Japan. In place of prescriptive solutions, a hierarchy of objectives/ functional requirements/ performance requirements was defined by a pair of design fire condition (input) and acceptable conditions (output). The critical values were selected so that the current prescriptive requirement would satisfy the criteria without too much redundancy. In this way, the system can derive many alternative design solutions without changing the absolute level of safety. As a first pilot case study, the system was applied to an four-storied multi-tenant office buildings. The study was carried out for control of fire spread and life safety verification.

在来構法木造住宅の実大水平力載荷実験

To investigate the horizontal resisting force capacity and failure processes of wood houses, four two-story houses and a wood frame-structure were examined. Prom the experimental results, the base shear coefficients which correspond to the maximum loading forces are about 0.4 - 0.5, the loading force at the deformation angle 1/120 rad is greater than those calculated from the values of effective multipliers of shear walls in the Building Standard Law, and these structures keep their bearing capacities up to the deformation angle of about 1/30 rad. The estimation methods of the effective multipliers of shear walls as well as the contributions of non-structural elements to bearing capacity are required.

性能的火災安全設計法によるテナントオフィスビルの防災設計

A pilot case study was carried out to examine the feasibility of a performance based fire safety design system to be developed in Japan. This system intends to give more degree of freedom in fire safety design than the method prescribed in current building standards law of Japan. In place of prescriptive solutions, a hierarchy of objectives/ functional requirements/ performance requirements was defined by a pair of design fire condition (input) and acceptable conditions (output). The critical values were selected so that the current prescriptive requirement would satisfy the criteria without too much redundancy. In this way, the system can derive many alternative design solutions without changing the absolute level of safety. As a first pilot case study, the system was applied to an four-storied multi-tenant office buildings. The study was carried out for control of fire spread and life safety verification.

1995年兵庫県南部地震における特定地域の鉄骨造建物被害調査

A field survey team investigated the damage to steel building structures that suffered from the 1995 Hyogoken-nanbu earthquake. The team investigated the damage to a total number of 628 steel buildings, located in the three specific areas of the city of Kobe, where many structures suffered significant damage, in order to find out the ratio of each damage level for all steel buildings in these areas. Among the investigated buildings, 109 were rated as Severe/Collapse, 90 as Moderate, 210 as Minor, and 208 as No damages. The results show that the ratio of the number of the buildings of Severe/Collapse damage, which were designed and constructed according to the current seismic provisions of the Building Standard Law of Japan, reduces to about one third of that according to the former ones.

銀座地区に取り残された居住環境 : 高容積率指定の商業地域における住環境に関する調査研究(2)

Most of the area sufferring from the extravagant population decrease in the center of Tokyo is designated as the commercial area under high Floor Area Restriction controls by the Building Standards Law and the City Planning Law. Here we chose GINZA as a typical example of this area. According to the research on the actual situation of the physical closeness of the residential environment in GINZA area, this study shows the nececssity to improve the environmental condition of houses such as sunshine, draft and daylighting.