Tạp chí KHCN Xây dựng - số 2/2006
Ngày tạo : 15/07/2015
Tạp chí KHCN Xây dựng - số 2/2006
Bàn về xử lý vi phạm chất lượng công trình xây
dựng,
PGS.
TS. Cao Duy
Tiến,
TS.
Nguyễn Hồng Hà
Tính
toán độ cố kết của nền đất yếu dưới tác dụng của tải trọng đắp,
GS. TS. Dương Học Hải
Đặc
điểm phá huỷ hệ thống đê sông đồng bằng Bắc bộ trong thời gian mưa lũ,
TSKH. Trần Mạnh Liểu
Cường độ chịu uốn của dầm bê tông
ứng lực trước căng sau không bám dính chịu tải trọng tập trung,
PGS.
TS. Nguyễn Tiến Chương
Một
số nội dung cần chú ý khi sử dụng tiêu chuẩn TCXDVN 356: 2005:Kết cấu BT và
BTCT- Tiêu chuẩn thiết kế,
TS. Nguyễn Võ Thông
Nghiên
cứu ảnh hưởng của Triethanolamine và bột đá vôi đến sự phát triển cường độ bê
tông và sự hình thành cấu trúc của đá ximăng Pooclăng,
TS. Nguyễn Như Quý
Một
số thay đổi của TCXDVN 239:2006 so với TCXD 239:2000,
TS. Nguyễn Đức Thắng
Thiết
kế chế tạo và sử dụng khung gia tải 50.000kN,
TS. Nguyễn Xuân Chính,
TS. Lê Minh Long
Hạ chìm kết cấu dạng thanh là vật rắn đàn hồi, đồng chất có tiết diện
thay đổi đều vào đất,
ThS.
Nguyễn Đắc Hưng
ABSTRACT
A
discussion on fining measures for quality violation to building structures (pp.
3-5)
A/Prof. Dr. Cao Duy Tien, Dr. Nguyen
Hong Ha
To manage the quality or
building structures, the Vietnamese Government has issued the Circular N0.
209/2004/ND-CP dated on December 16, 2004. Equivalent to this Circular, the
People’s Republic or China
has also issued the Circular N0. 279 on January 30, 2000 signed by
the Primer Minister Zhu Rongji (Chu Dung Co in Vietnamese). In this paper, the
authors introduce in detail the Chinese Circular to whom it may concern in
order to learn the experience on quality management of building structures by
the People’s Republic of China
to improve our Circular, in terms of: specific regulations on money punishment
and administrative punishment applied to individuals, organizations violating
the quality of building structures. In addition, the administrative
institution, who is responsible for performing these regulations should also be
stated in our Circular.
Calculation of soft soil consolidation subjected to filled soil load (pp. 6-7)
Prof.Dr.
Duong Hoc Hai
This paper presents the calculation of soft soil consolidation subjected to
filled soil load in case the depth of sand drain (sand well) or the depth of
band drain does not reach the bottom of the stratum that causes the settlement.
This is a valuable applied and research result of the author as a member of the
State Acceptance Council on the quality of bridge and roadconstruction.
Deterioration characteristics or the system of river dikes in the Red river
delta during the rainy and flood season (pp. 8-11)
Dr. Sc.
Tran Manh Lieu
The system of river dikes in the Red river delta in
the rainy and food season are usually damaged due to two scenarios: first, due
to permeable instability of the embanlmentand the seceond, due to permeable
instability of the base under the dike. This paper presents the behaviour,
mechanism and stages of development of dike damage process according to the
above scenarios and proposes the solution for protecting the dikes against the
damage.
Flexural strength of unbonded post-tensioned prestressed concrete beams subjected to concentrated
load(pp. 12-17)
A/Prof. Dr. Nguyen Tien Chuong
The feature of
unbonded post-tensioned prestressed concrete structures is there is no
simultaneous deformation between the unbonded prestressing steel (tendon) and
the remaining structure. It makes the study on the behaviour of unbonded
prestressing steel when calculating the bearing capacity of the structure
become difficult. Therefore, many experimental formulae have been recommended
to be applied in the design standards and many shortcomings have been
encountered by Designers. In this paper, the author presents a study on
flexural strength of unbonded post-tensioned prestressed concrete beams
subjected to concentrated load in order to make a contribution to the limiting
the above shortcomings in the design standards.
Attentions required to be paid when applying
TCXDVN 356:20005: Concrete and reinforced concrete - Design standard (pp. 18-23)
Dr. Nguyen Vo Thong
In this paper, the auhor
presents the new contents of the TCXDVN 356:20005: concrete and reinforced
concrete - Design standard that shoud be paid attention to when applying. The
contents required to be paid attention to are: the scope of application, new
regulations relating to concrete and reinforcing steel, the structural
analysis, and so on..
Studying on the influence of triethanolamine and lime stone powder on the
development of concrete strength and the formation of Portland cement stone
structure (pp. 24-31)
Dr. Nguyen Nhu Quy
The presence of finely
ground limestone powder in concrete becomes more and more popular due to its
ability to upgrade several properties of concrete. When the limestone powder is
used in concrete in combination with triethanolamine (TEA) as an accelerator
the hydration and hardening process of Portland cement is likely changed. This
study reported the results of the authors’ research on the effect of TEA and
limestone powder on strength development of concrete with varying water-cement
ratio using statistic design of experiments. The results of SEM and X-ray
examination reveal that TEA has a rather profound influence on the concrete
strength development as well as the formation of hardened Portland cement paste
structure.
Some modifications ofTCXDVN 239:2006 compared toTCXD 239:2000 (pp. 32-33)
Dr.
Nguyen Duc Thang
In 2000, Ministry of Construction
issued TCXD 239:2000 "Heavy concrete. Guide to assessment of concrete
strength in existing structures:" This standard has made a significant
contribution to the improvement of concrete quality control. However, the
systematism of the standard is not reached, some terminologies are not
consistent and some formulae are not correct. Therefore, this standard has been
reviewed and replaced with TCXDVN 239: 2006. In this paper,the author
introduces the difference between TCXD 239:2000 and its latest version, TCXDVN
239: 2006.
Design, production and utilization of steel frame for load test up to
50,000kN(pp. 34-38)
Dr. NguyenXuan Chinh, Dr. Le Minh
Long.
Load test steel frame is a welded space steel
plate structure utilized for big load test. In the recent years, the
requirement on testing of bridge bearings subjected to big loads is increasing
and this has been performed in foreign countries. In this paper, the authors
present the calculation, design and production of a Load test steel frame at
IBST that can be used for load test up to 50,000kN. The said load test steel
frame has been applied sucessfully to the load test of the roof’s beam bearing
of the main building – the National Convention Centre (20,000kN), the bearing
of Rach Mieu bridge in the national road N0. 60 (25,000kN) accroding
to technical requirements in the test procedure stated by the Designer.
The subsidence of an
elastic uniform rod-like structure with variable cross-section into the soil
(pp. 39-45)
MEng. Nguyen Dac Hung
Up to now, the problem of subsidence of an
elastic uniform rod-like structure with variable cross-section into the soil,
which is subjected to compulsory force induced by two vibrators and to lateral
and tip resistance force,has not been solved. In this study, the author has
solved the problem by finding out the geometric solution of the problem and by
determining the displacement function at the middle cross-section of each part
or at the middle cross-section of the whole structure corresponding to each
interval or the whole time of subsiding.
The result of this study cannot only be the theoretical basic for
solving the problem of subsiding an elastic uniform rod-like structure with
variable cross-section into the soil, but also applicable to solving the
problem of pulling out of structure with a vibration method.
