Editors: Kyuichi Maruyama and Andrew W. Taylor

The First American Concrete Institute (ACI) and Japan Concrete Institute (JCI) joint seminar was conceived as a vehicle for promoting collaboration and cooperation between two organizations that are dedicated to the global advancement of concrete technology. In September 2012 ACI President James Wight, and ACI Executive Vice President Ronald Burg, visited the headquarters of JCI and discussed ways to promote collaboration between ACI and JCI with JCI President Taketo Uomoto and JCI Executive Directors. A joint ACI and JCI technical seminar was proposed as a way to share knowledge and foster collaboration between the two organizations. Subsequent discussions between Ronald Burg and JCI Executive Director Kyuichi Maruyama led to a joint seminar planning meeting, held at the ACI convention in Minneapolis, Minnesota, in April 2013.

This volume contains the technical papers presented at the First ACI & JCI Joint Seminar, held in Waimea, Island of Hawaii, Hawaii, July 16 to 18, 2014. The theme of the joint seminar was “Design of Concrete Structures Against Earthquake and Tsunami Disasters.” Five papers were presented by authors from ACI, and five papers from JCI. Three papers are related to tsunami loads and structural design requirements, and seven are related to seismic analysis and design.

The three papers on tsunami effects included a summary by Nakano of structural design requirements for tsunami evacuation buildings in Japan; an overview by Chock of the new tsunami load and design requirements in the United States; and a study by Maruyama et al. on the evaluation of tsunami forces acting on bridge girders.

The seven papers on seismic effects addressed topics ranging from seismic design standards to innovative methods of construction for seismic retrofit. Parra-Montesinos et al. presented the results of experiments on fiber-reinforced coupling beams, as well as design guidelines. Teshigawara discussed JCI contributions to the ISO Standard for seismic evaluation and retrofit of existing concrete structures. A summary of a project on the use of high-strength reinforcement for seismic design was presented by Kelly et al., including findings that are based on extensive prior research on high-strength reinforcement in Japan. Shiohara described the results of a study that supports the new Architectural Institute of Japan (AIJ) Standard for Seismic Capacity Calculation, with a focus on beam-column joints and collapse simulation. Matamoros presented a study of factors that affect drift ratio at axial failure of nonductile reinforced concrete buildings. A study of the seismic response of reinforced concrete bridge piers, including the effects of interaction between piles and soil, was presented by Maki et al. Finally, French et al. discussed an overview of lessons learned from laboratory testing of reinforced concrete shear walls.

The day after the joint seminar a meeting was held between ACI and JCI officials to discuss future collaboration and joint seminars. Representing ACI were President William E. Rushing, and the ACI Executive Vice President, Ronald Burg. Representing JCI were President Hirozo Mihashi, and Chair of the JCI Committee on JCI-ACI Collaboration, Kyuichi Maruyama. It was resolved to hold a second joint seminar, to be hosted by JCI in Tokyo, in conjunction with the 50th anniversary celebrations of the founding of JCI on July 13, 2015. In addition, subsequent discussions between ACI and JCI led to plans for the third joint seminar, to be hosted by ACI at the ACI Convention in Anaheim, California, in October 2017.

It is hoped that this collection of papers will serve to advance the state of analysis and design of concrete structures against earthquakes and tsunamis in both the United States and Japan, and that it will serve as a model for future collaboration between ACI and JCI.

Note: The individual papers are also available. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP-313

A new concept of joint hinging developed in Japan is presented, which will be implemented in a new draft provision for beam-column joints in the New AIJ (Architectural Institute of Japan) Standard for Seismic Capacity Calculation. This paper discusses the key issues of the new draft provisions, with background, test data verification, theory and analyses with emphasis on why such a concept is necessary. The factors affecting joint hinging failure are discussed for seismic design consideration. Seismic collapse simulation were made by non-linear time history analysis for moment frames with BC joints failing due to joint hinging, to demonstrate the challenge of simulated strength degradation and severe pinching hysteretic behavior inherent to joint hinging. Draft equations to calculate the strength of joint hinging strength of BC joints are also introduced.

After the Kobe earthquake in 1995 in Japan, many reinforced concrete (RC) bridge piers have been strengthened using various techniques, such as steel jacketing and concrete jacketing. It is anticipated that, when the next strong earthquake comes, foundations will possibly be damaged because of the enhanced capacity of the pier. In this paper, the seismic response of reinforced concrete (RC) bridge piers and foundations were evaluated using the substructure pseudo-dynamic (S-PSD) testing method for cases in which strengthening was provided to the pier and foundation. The S-PSD testing method for bridge pier-foundations was first developed. Based on the developed method, damage in a foundation that supported a strengthened pier was investigated through a pier specimen loading. In addition, the response of a strengthened bridge pier with a strengthened foundation was also examined through a foundation specimen loading. The possibility of foundation damage due to pier strengthening and the effectiveness of foundation strengthening were finally confirmed.

Since the late 1990s many physical simulations of nonductile reinforced concrete columns have been performed in North America with the goal of identifying the key parameters that affect the collapse safety margin of buildings during earthquakes. The first comprehensive study on this topic in North America focused on the behavior of nonductile flexure shear-critical columns with reinforcing details commonly used prior to 1970. These early experiments evaluated the effect of axial load and amount of transverse reinforcement on the drift ratio at axial failure of columns, and led to the development of a shearfriction failure model. A recent experimental program funded by the National Science Foundation significantly expanded the experimental data set on column axial failure under load reversals. Experiments were conducted to investigate the behavior of shear-critical columns, and to evaluate the effect of shear span-to-depth ratio and displacement history on the drift ratio at axial failure of nonductile columns. The main findings of this experimental program are presented.

In the U.S., the specified yield strength of primary reinforcement of special concrete moment frames and special concrete shear walls may not exceed 60 ksi. As part of the Applied Technology Council ATC-98 Project, the use of high-strength reinforcement as primary reinforcement for seismicforce-resisting systems (SFRS) was studied. The purpose of the project was to examine the feasibility of using reinforcement with a specified yield strength greater than 60 ksi and, if feasible, to recommend changes in design requirements and reinforcing steel specifications. The use of ASTM A706 Grade 80 was specifically examined, and it was determined that Grade 80 reinforcement could be used with little change to ACI 318. It was also found that additional research is needed before complete recommendations for use of Grades 100 and 120 reinforcement can be made.