Ngày tạo : 20/02/2017
Tính toán sự cố rủi ro của công trình xây dựng, download
PGS.TS. Nguyễn Xuân Chính, ThS. Nguyễn Hoàng Anh
Ứng dụng thuật toán tiến hóa vi phân đột biến hỗn hợp (hcde) xác định tần số dao động riêng của kết cấu khung phẳng có tham số đầu vào dạng số khoảng, download
ThS. Đặng Hồng Long, TS. Lê Công Duy, TS. Hoàng Nhật Đức
Mô phỏng cột ngắn ống thép nhồi bê tông cường độ cao chịu tải trọng nén đúng tâm, download
ThS. Phan Đình Hào, KS. Trịnh Hữu Hiệp
Tham số tối ưu của bộ hấp thụ dao động TMD-D cho con lắc ngược theo phương pháp cực tiểu hóa năng lượng, download
TS. Nguyễn Duy Chinh
Xác định tần số dao động riêng cơ bản của kết cấu thép chân đế giàn khoan biển bằng phân tích kết quả phản ứng động, download
TS. Nguyễn Thành Trung
Nghiên cứu một số vật liệu xây dựng nguyên gốc của nhà thờ Đức Bà Tp. Hồ Chí Minh phục vụ trùng tu, download
ThS. Uông Hồng Sơn, TS. Trần Minh Đức, KS. Nguyễn Thành Thái
Nghiên cứu tối ưu hóa yếu tố nhiệt độ trong chế tạo vật liệu cốt thủy tinh Composite Polymer, download
ThS. Bùi Thị Thu Phương, PGS.TS. Nguyễn Võ Thông, TS. Nguyễn Thế Hùng
Phân tích giới hạn hội tụ và lý giải nguyên nhân việc không hội tụ của phương pháp newton khi áp dụng tính toán cho mô hình thép tinh thể, download
TS. Nguyễn Cẩn Ngôn
Giải pháp thi công tầng hầm bằng cách dùng dầm bailey lắp trực giao để văng chống hố móng, download
GS.TSKH. Nguyễn Đăng Bích, ThS. Nguyễn Thế Toàn
Nghiên cứu sự làm việc của cọc đơn thông qua hiệu chỉnh đường cong T-Z ứng với số liệu nén tĩnh cọc, download
ThS. NCS. Phạm Tuấn Anh,PGS.TS. Nguyễn Tương Lai,TS. Trịnh Việt Cường
Phân tích các thông số ảnh hưởng đến ứng xử của tường chắn đất có cốt, download
ThS. Nguyễn Thị Ngân, TS. Phạm Quyết Thắng
Dự báo nguy cơ trượt đất khu vực xã Nấm Dẩn huyện Xín Mần, tỉnh Hà Giang, download
ThS. Nguyễn Quang Huy, PGS.TSKH. Trần Mạnh Liểu,ThS. Hoàng Đình Thiện, KS. Nguyễn Thị Khang, CN. Bùi Bảo Trung
ABSTRACT
Calculation of risk incidents of buildings and structures (pp.3-9)
A/Prof. Dr. NGUYEN XUAN CHINH, MEng. NGUYEN HOANG ANH
In analysis and design of buildings and structures although the reliability coefficients of loads, materials, working conditions to ensure the use safety of the structure. However, the buidings and structures still have potentially risky incidents during their sevice life. Calculations and forecast of risk incidents will recommend the plan of the exploitation, maintenance and repair in order to ensure safety and to improve the effective exploitation of the structure. This paper presents a method of calculating risk incidents for buildings and structures.
Applying hybrid crossover differential evolution to determine eigenfrequency of a plane frame structure that has aninterval-valuedinput data (pp.10-16)
MEng. DANG HONG LONG, Dr. LE CONG DUY, Dr. HOANG NHAT DUC
Recently, analysing the dynamic of structure withinterval-valued input datais a particularly interesting problem. The difficulty of the problem will escalate when input data take form of interval-valuedvariables. In this paper, the authors present a method that appliesa novelHybrid Crossover Differential Evolution – HCDE to determine the eigenfrequency of a plane frame structure. A numerical example witha steel frame of one span and four stories that has interval-valued input data ofthe cross section, moment of inertia, modulus of elasticity of material, length of span, height of storywill be presented to illustrate theapplication of proposed approach.
Key word: dynamic, hybrid crossover, differential evolution, eigenfrequency.
Simulating short CFST columns using high strength concrete in fill under centrically compressive loading (pp.17-25)
MEng. PHAN DINH HAO, Eng. TRINH HUU HIEP
The ultimate strengths of concrete filled steel tube (CFST) columns under the axial compressive loading principally depend on the properties of constituent materials. Furthermore, the behaviour of the columns is also affected by confinement of the concrete core offered by the steel tube and geometric properties of the steel tube such as the cross-section and the width-to-thickness ratio. This study used ABAQUS software to investigate the influence of the concrete strength to the bearing capacity of CFST columns subjected to axial compressive loads. In order to improve knowledge related to mechanical behaviour of the columns as well as the efficient use of high-strength concrete filled, the three-dimensional nonlinear finite element models were established and conducted numerical analysis processes used for short CFST columns. The study was conducted with three different loading conditions including only loading on the concrete core, only loading on the steel tube and simultaneously loading on both the concrete core and steel tube. The investigation outcomes showed that the CFST column loaded only on the concrete core has the highest loading capacity, moreover the loading capacity of CFST columns increase when increasing the concrete compressive strength.
Key words: Concrete filled steel tube (CFST) columns; ultimate compressive strength; high-strength concrete; confinement effect; mechanical behaviour; axial compressive load; local buckling.
Optimal parameters of vibration reduction system TMD-D for an inverted pendulum type structure by using the energy minimization method (pp.26-31)
Dr. NGUYEN DUY CHINH
Investigation to reduce the oscillation for structures by using the TMD passive absorber is an important research fiel and is addressed by many scientiests in Vietnam and all over the world. In this paper, a method is proposed for searching an analytical solution of optimal parameters of the TMD-D passive absorber for inverted-pendulum system. Then, the proposed method is applied to reduce the oscillation of one-span traffic bridge. Numerical study is implimented to validate the proposed method by using the Mapple software.
Determination of Fundamental natural frequecies of steel jacket offshore platform by dynamic response analysis (pp.32-39)
Dr. NGUYEN THANH TRUNG
Determination of dynamic characteristics is one important step in a maintenance work of offshore platform under operation. Recently, most of the calculation programs have been only provided natural frequenciesconsidering of a linearity of the structural system. Therefore, the determination of the frequency variationdue to a nonlinear effect underextreme environmental loads has been much interested. This paper presents the method of determining fundamental natural frequenciesof steel jacket offshore platform by analysing the dynamic responses data from numerical model using Fast Fourier Transform (FFT). The influence of nonlinear behavior of structure and the soil-pile interaction were considered in this study.
Look at some of the original building materials of Notre Dame Cathedral in Ho Chi Minh City in service restoration (pp.40-48)
MEng. UONG HONG SON, Dr. TRAN MINH DUC, Eng. NGUYEN THANH THAI
Notre Dame Cathedral Basilica of HCM City is a specific historical values, religion, important architecture of this city. After more than 135 years of existence, the Notre Dame Cathedral now has some phenomena of damages and degrades. The research group has done some investigations for the purpose of helping restored some of the main construction material of the building.
Optimization of temperature factors in manufacturing reinforced composite polymer (pp.49-53)
MEng. BUI THI THU PHUONG, A/Prof.Dr. NGUYEN VO THONG, Dr. NGUYEN THE HUNG
Manufacturing technology of reinforced polymer composite materials using thermoplastic resin epoxy curing agent was accompanied by the method of forming solidify rapidly in small diameter pipe heating but long enough. Optimization temperature factors in the different segments of the heat pipe is the aim of this study. That allows more complete manufacturing technology of reinforced polymer composite materials in Vietnam.
Analysis convergence limit and explanations the causes of non convergence when using Newton’s method to calculate steel crystal model (pp.54-57)
Dr. NGUYEN CAN NGON
The article focuses on analyzing the convergence limit and explain the causes of non convergence when using Newton's method to calculate steel crystal model. This article in turn presents: problems encountered, crystal steel model, explainations with illustrations for non-convergence cases.
Keywords: Newton numerical integration, steel crystal models, convergence, divergence, bainite steel
Solution for basement construction by using Balley beams orthogonally installing to prop up excavation pit (pp.58-64)
Prof. Dr. Sc. NGUYEN DANG BICH, MEng. NGUYEN THE TOAN
Bailey beams are often used as a temporary bridge and working flatform in constructing traffic works. Bailey beams have been used to prop up excavation pit with a parallel installation and pass aperture 27m. The research results in this paper show that using Bailey beam installed orthogonally to prop up excavation pit can be over aperture more than 27m.
Research single pile under axial load by calibration T-Z curve using static pile compression test (65-70)
MEng. PHAM TUAN ANH, A/Prof. Dr. NGUYEN TUONG LAI, Dr. TRINH VIET CUONG
This paper presents the results of the research on the behaviour of single pile by using T-Z curve. Actually, the modern equipment allows the monitoring of the deformation along pile shaft during static compression test. Thus, beside the measurement of pile head displacement, the axial load transfer along the pile shaft is also determined, from which the calibration of T-Z curve to the test results. Such a calibration provides to the designer simple T-Z curves for the analysis of single piles with relatively accurate and reliable results.
Keywords: Single pile, pile – soil interaction, calibration of T-Z curve.
Behavior of reinforced soil walls (71-79)
MEng. NGUYEN THI NGAN, Dr. PHAM QUYET THANG
This paper presents the research results based on analytical and numerical analyses to predict the behavior of reinforced soil walls with veriable parameters. The main parameters such as reinforced spacing, length of reinforcement, and strength of the reinforced layers are analyzed using the software Phase2. The recommendations for design and construction of reinforced soil walls are mentioned.
Risk Forecast of Landslide in Nam Dan areas, Xin Man District, Ha Giang Province (80-88)
MEng. NGUYEN QUANG HUY, A/Prof.Dr.Sc. TRAN MANH LIEU, MEng. HOANG DINH THIEN, Eng. NGUYEN THI KHANG, Ba. BUI BAO TRUNG
The paper introduces the methods and procedures to calculate the risk of landslides forecast for Nam Dan areas, Xin Man district, Ha Giang province, where the landslide occurred on a large scale with sliding blocks large and very large. Method of landslide risk assessment is the method integrating statistical indicators multivariate. Based on the current status of the study area, the factors which decides the landslides are taken into account the geological lithology, DEM, slope, horizontal terrain and vertical terrain differentiations, distances to the road, to the lineament, the existing land use. Weights of the factors (causes sliding role) is calculated through formula quantified by a research team of the Centre for Urban Studies - VNU proposal. Result mapping landslide risk assessment is based on the index value maps prone land landslide hazards are calculated in the GIS for the study area based on a formula recommended by Voogd (1983).