Tạp chí Khoa học Công nghệ Xây dựng số 1/2014
Ngày tạo : 01/07/2015
Tạp chí Khoa học Công nghệ Xây dựng số 1/2014 TS. Cao Duy Khôi
Một số thay đổi chủ yếu trong dự thảo tiêu chuẩn thiết kế kháng chấn mới của Việt Nam TCVN "Xây dựng công trình trong vùng động đất",download
ThS. Phạm Nhân Hòa, PGS. TS. Chu Quốc Thắng, ThS. Lê Minh Thành
Giảm chấn cho kết cấu 20 tầng chịu tải trọng động đất bằng hệ cản chất lỏng nhớt được điều khiển tự động khi xét đến phi tuyến vật liệu, download
ThS. Trần Thanh Tuấn, TS. Nguyễn Hồng Ân
Phân tích ứng xử nhà cao tầng chịu động đất bằng phương pháp tĩnh phi tuyến dựa trên phổ khả năng, download
ThS. Phạm Đức Cương
Thiết kế cấu kiện cơ bản bê tông cốt thép theo chỉ số độ tin cậy, download
TS. Hoàng Minh Đức
Đánh giá và nghiệm thu bê tông có tính đến biến động cường độ, download
PGS.TS Trần Nhất Dũng, Th.S Hoàng Giang
Nghiên cứu thiết kế chế tạo cụm bánh xe tự điều chỉnh độ cao cho đường triền có hai đoạn cong quá độ sử dụng hơn hai xe chở tàu, download
TS. Nguyễn Minh Tâm, ThS. Nguyễn Bửu Anh Thư
Nghiên cứu phương pháp tính áp lực đất cho tường vây hố đào sâu, download
ThS. Trần Ngọc Đông, ThS. Nguyễn Hà
Phương pháp kiểm tra sai số vượt giới hạn trong các trị đo quan trắc lún công trình, download
Major changes in the draft standard for earthquake resistance design of Vietnam TCVN “Building in earthquake area”
Dr. Cao Duy Khoi
Earthquake is an important action to be considered in building design. Before 2006, Vietnam had no official seismic design standard. Since 2006, TCXDVN 375:2006 (currently TCVN 9386:2012) basing on Eurocode 8 has been implemented in Vietnam. In addition to that, engineers may use other foreign standards for design such as UBC 97, IBC. However, seismic design standards from Western countries and Vietnam are not fully compatible due to the fact that this system is mainly based on Russian standards. Therefore, compiling a new seismic design standard of Vietnam based on the new Russian standard SP 14.13330.2011 is necessary. This article summarises and analyses major and important changes in the Russian standard SP 14.13330.2011 in comparison to the previous edition of seismic design standard of Russia (SNiP II-7-81*).
Seismic resistance of non-linear 20-story building using passive viscous fluid dampers with consideration to nonlinearity of material
MEng. Phạm Nhan Hoa, A/Prof.Dr. Chu Quoc Thang, MEng. Le Minh Thanh
The paper presents the mechanic model (assumed as a shear frame model), differential equation of motion, and algorithm to calculate the response of a 2D frame where material has a perfect elastic-plastic behavior and the frame is equipped with passive viscous fluid dampers (VFD). A numerical example is a 20 storey plane steel frame subjected to the Kobe earthquake. The structure is analyzed for four cases: elastic behavior, inelastic behavior, with VFD and without VFD. The results from example of numerical analysis serve to compare the effectiveness in reducing response of a structure using passive VFD and elastic behavior with that of a structure using passive VFD and inelastic behavior.
Nonlinear pushover analysis procedure based on the capacity spectrum method for seismic evaluation of high-rise buildings
MEng. Tran Thanh Tuan, Dr. Nguyen Hong An
In this paper, the Modal Pushover Analysis (MPA) has been extended to estimate seismic demands for high-rise buildings, inwhich the target displacement is calculated using Capacity Spectrum Method (CSM).
Design basic reinforced concrete structural elements according to the reliability
MEng. Pham Duc Cuong
Limit State Method is widely used around the world (including Vietnam) to establish the design standards for reinforced concrete structures. Currently, some developed countries have conducted researches and used the design standards for reinforced concrete structures basing on the reliability in order to reflect more accurately the real nature of the behavior of structure. In this article, the author presents a design method of basic reinforced concrete elements according to the reliability index. Some remarks are made at the end of the article.
Strength variation in conformity evaluation of concrete
Dr. Hoang Minh Duc
Variation in compressive strength is the nature of concrete and must be taken into account when assessing the conformity. This paper reviews the requirements and standard methods for within test variations in comparison with those in Vietnam. Concerning between test variation, the basic principle and criteria for conformity assessment are summarized. It shows that the current conformity criterion in Vietnam is not appropriate and needs to improve. The proposal to revise standard assessment procedure and criteria is also given.
Design and manufacture self-raising vehicle for slipway with two transitional curves, using more than two ship forklifts
A/Prof.Dr. Tran Nhat Dung, MEng. Hoang Giang
The article mentioned the practical demand and scientific significance of the research and manufacture of wheel assemblies that can automatically adjust the height for slipway with two transitional curves. The proposal of combination of hydraulic cylinders and associated accummultor for creating a self-raising vehicle which has important ability of maintaining the reaction on bilge (load exerted on the vehicle wheels) within small margin (± 1.5% around the average value) althogh the height varies in a large range.
Research into suitable method to calulate soil pressure on diaphragm wall of deep excavation
Dr. Nguyen Minh Tam, MEng. Nguyen Buu Anh Thu
Nowadays, high rise buildings with deep basements are in a bloomed development. It has become a indispensable tendency in the modernization of major cities.
The author intruduces a method of analysis of soil pressure and design the cantilever retaining structures. It bases on the limit equilibrium methods, but it uses some additional conditions for interaction between the retaining structure and the ground, when referring to the distribution of the mobilized earth pressures on the structure. The main benefit of the proposed method is shown in the analysis of the structures in layered ground (heterogeneous above the dredge level and homogeneous below it), and in the considering of possibility of the influence of surcharge loadings on the active or passive side of the retaining structure. When analyzing such cases in practice, the proposed method gives results which are in better agreement with the results of FEM based elasto-plastic interaction analyses than with the results of currently used methods. At the same time, its results are in accordance with those published for homogeneous cohesionless ground because in practice, almost all retaining structures are erected in layered ground (heterogeneous above the dredge level and homogeneous below it).
Methods of checking errors exceeding the limits in monitored values of settlement of constructions
MEng. Tran Ngoc Dong, MEng. Nguyen Ha
This article presents the methods for identifying the values from measured settlement of constructions with errors exceeding the limits in the data-processing procedure. This helps to select the monitored values to be processed in order to improve the reliability of the settlement monitoring work.