Dao động của kết cấu khung thép có liên kết mềm phi tuyến
ThS. Nguyễn Hồng Sơn, ThS. Võ Thanh Lương
Phân tích ổn định của thanh bằng phương pháp ma trận độ cứng động lực
TS. Trần Văn Liên
Bài toán ổn định đàn hồi của kết cấu vỏ thoải mặt bằng hình chữ nhật với các liên kết biên khác nhau
PGS. TS. Lê Ngọc Thạch, ThS. Mai Châu Anh
Ảnh hưởng của địa hình đến áp lực gió
KS. Ngô Tất Thành
Phục chế gạch Bát Tràng men để tu bổ di tích Thế Tổ miếu và Hưng miếu
TS. Nguyễn Tiến Bình, KS. Mai Xuân Hiển
Nghiên cứu ứng dụng sơn kỵ nước cho tường ngoài công trình xây dựng
TS. Hoàng Minh Đức
Nghiên cứu ảnh hưởng của tỷ lệ hướng sợi đến cường độ của bê tông cốt sợi thép
ThS. Nguyễn Thanh Bình, TS. Trần Bá Việt
Nghiên cứu độ ổn định theo thời gian của chất ức chế ăn mòn cốt thép canxi nitrrit trong bê tông
ThS. Nguyễn Nam Thắng, TS. Phạm Văn Khoan, TS. Lê Quang Hùng
Phòng ngừa một số tai biến địa kỹ thuật môi trường do khai thác nước ngầm tại Hà Nội.
TSKH. Trần Mạnh Liểu, TS. Nguyễn Văn Đản
Thổi rửa và bơm phụt vữa gia cường chân cọc khoan nhồi - một công nghệ đạt hiệu quả cao trên địa bàn Hà Nội
ThS. Nguyễn Văn Khánh, ThS. Trần Nhật Thành
Một phương pháp xác định tuổi thọ và tuổi thọ còn lại của công trình
TS. Nguyễn Văn Hùng
Abstract
Vibration of steel frames with nonlinear flexible connections (pp. 3-6)
MEng. NguyenHongSon, MEng. Vo Thanh Luong
This paper presents the dynamic of steel structures with nonlinear semi-rigid connections, modelized by three springs with nonlinear flexibility coefficient, the establishment of the differential equation of motion including damping of this structure subjected to the periodic dynamic loading. The solution of this differential equation is obtained by using the combination of Newmark’s direct integral method and Newton-Raphson’s modified interaction method. MATLAB is the programming language of software. Some numerical examples are introduced for verifying the justification of algorithm.
The analysis of stability of frame and beam structures by applying dynamic stiffness matrix method
Dr. Tran Van Lien
In this paper, the author presents the application of the dynamic stiffness matrix in the analysis of the stability of frame and beam structures in compression by the conservative and non- conservative force such as the follower force under the form of the criterion of dynamic stability. The author has already found the familiar results of the analytic method. This study can be used in teaching, doing scientific research and making calculations.
Instability of shallow shell of rectangular baseand with different boundary conditions
A/Prof. Dr. Le Ngoc Thach, MEng. Mai Chau Anh
The problem of the elastic instability of shallow shell of rectangular base and with four simply supported edges was solved by A. C. Volmir. With different boundary conditions other than that investigated by A. C. Volmir, the analytic solution of this problem is quite complicated. Based on results of A. C. Volmir and by applying some of the modern computer software, this paper presents results of the analysis of the elastic instability of shallow shell of rectangular base and with different boundary conditions.
Topographic effects on wind pressure on buildings
Eng. Ngo Tat Thanh
This paper discusses topopgraphic effects on wind pressure on buildings. Different approaches accounting for the topographic effects in TCVN 2737-95, ASCE/SEI 7-2005, and AS/NZS 1170.2: 2002 are reviewed and compared. Examples of the effects obtained by using these three building codes are given and analyzed.Revealed existing problems among these codes will be useful for code revision work and further research. This paper may also be considered as guidance for calculating wind pressure on the buildings on complex topographic features especially in Vietnam where materials discussing this topic are still limited.
Restoration of the Bat Trang yellow and green enamelled tiles for conservation of The To and Hung temple monuments (pp. 29-33)
Dr. NguyenTien Binh, Eng. Mai Xuan Hien
The Bat Trang yellow and green enamelled tiles have been widely used in the Hue different monuments such as in the palaces: Minh Thanh palace- Gia Long tom, Sung An Palace-Minh Mang tomb Hoa Kham palace -Tu Duc tomb; in some important gates and Pavilions. At present, The Bat Trang enameled tiles in these monuments have been very much deteriorated: many tiles are cracked or their enamel on the tile surface is scaled off. The restoration of the original shape and colour for the tiles is one of the matters of concern in the cause of restoration and conservation of the Hue monuments.
In this paper, the authors present some research results on restoration of the Bat Trang enameled tiles for conservation of the To and Hung temple which belong to the complex of Hue monuments.
Studying on the application ofhydrofobic paint to external walls of building structures (pp. 34-39)
Dr. Hoang Minh Duc
Improving performance and durability of the mineral coating can be done by hydrofobization, which reduces water absorption while keeping moisture vapor transmission unchanged. Laboratory investigation and site application, conducted in IBST in frame of the research project RD 29-04, show advantages of the external hydrofobic paint made from traditional limestone and cement paints with hydrofobic admixture SK-5E as a high effective finishing material for restoration of hystorical structures as well as for construction of civil and industrial buildings.
Studying on the influence of the length to diameter ratio (l/d) on the strength of steel fiber reinforced concrete (pp. 40-43)
MEng. Nguyen Thanh Binh, Dr. Tran Ba Viet
The superiority of using steel fibers in steel fiber reinforced concrete, compared to other artificial fibers, is that it makes the flexural and tension strengths of concrete increased significantly. The increase rate of flexural and tension strengths of steel fiber reinforced concrete, in comparison with that of non-fiber concrete, depends on many factors among which, the influence of the length to diameter ratio (l/d) on the flexural strength of steel fiber reinforced concrete is very big. In this paper, the authors present a study on the length to diameter ratio (l/d) on the flexural strength of steel fiber reinforced concrete whose strength is limited in the range from 300 to 800daN/cm2, in order to obtain maximum effectiveness of the use of steel fibers in steel fiber reinforced concrete.
Studying on time-dependent stability of calcium nitrite corrosion inhibitor in concrete (pp. 44-47)
MEng. Nguyen Nam Thang, Dr. Pham Van Khoan, Dr. Le Quang Hung.
This paper presents some research results on the stability of calcium nitrite corrosion inhibitor in different concrete grades by the accelerated laboratory tests. Based on these results, the authors introduce the way to use effectively calcium nitrite corrosion inhibitor in preventing reinforcements in concrete from corrosion.
Prevention of geotechnical-environmental risks due to underground water intensive exploitation in the Hanoi region (pp. 48-54)
Dr. Sc. Tran Manh Lieu, Dr. Nguyen Van Dan
Underground water intensive exploitation is one of the socio - economical activities in the Hanoi regionand leading inevitably to many geotechnical - environmental risks.
This paper deals with some geotechnical - environmental risks su ch as ground settlement, building damage and underground water pollution, pile negative friction in the Hanoi region and some measures to prevent them.
Bottom cleaning and post grouting for bored piles - a high effective technique in the Hanoi construction sites (pp. 55-57)
MEng. Nguyen Van Khanh, MEng. Tran Nhat Thanh
In this paper, the authors present the result of a scientific reseach theme on the increase of the bearing capacity of bored piles by bottom cleaning and post-grouting technique applied to construction sites in Hanoi. It is shown that in the soil conditions of Hanoi area, if the above technique is strictly applied, the bearing capacity of bored piles can be increased 1.5 times in comparision with that ofbored piles without applying this technique.
A methof for determination of the lifetime and remaining lifetime of building structures (pp. 58-60)
Dr. Nguyen Van Hung
In this paper, the author introduces a method for determination of the lifetime and the remaining lifetime of building structures on the basis of the reliability of structures. To apply this method, it is required to be provided with sufficient statistical data.