CÂU hỏi lý thuyết ôn tập tổ CHỨC THI CÔNG

CÂU HỎI ÔN TẬP TỔ CHỨC THI CÔNG
1. Khi nào cần điều chỉnh tiến độ thi công? Nêu và giải thích các
phương pháp điều chỉnh tiến độ thi cơng?
- We need to optimize the schedule because:
First draft of network diagram is often inaccurate and does not meet standard.
For example, when the time in diagram larger than details in regulation or in
bidding document and there are cases in which resource demand are unevenly
distributed overtime, sometimes exceed (or being utilized improperly) the
limitation of practical providing.  thus it should be optimized.

- There are several methods:
• Optimising time: Shortening implementation time of work by executing

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critical tasks.
• Technical solution: make changes of technical solution or material used
(especially new materials, etc.), when conducting this, technical quality
must be ensured (require high level of workmanship, mechanical
equipment, and implementation methods).
• Economic solution: extending time for uncritical tasks in order to reduce
resources used and accumulate saved resources for critical tasks, increase
work shifts, as well as number of unit of workers and machine (at the
same time), etc. Working ground needs to be enough while achieving this
method.
• Note that relationships among tasks must be technically secured when
shortening project time and rising budget for shortening is reasonably as
low as possible.
Using organizational solution, especially stream line method, to reduce time
cost for critical tasks, or group of tasks that affect project’s finish
milestone.This solution makes no increase in resources cost, no technical

change but still reduce construction time; therefore this is the leading basic
method.
Optimising resources:
• When issues need to be fixed fast and relatively, quick adjustment method is
used.
• Following 2 steps:
Step 1: Translate network diagram into time axis or bar chart (based on its
complexity)
Determine the average of resources Rtb : Rtb = Q/T
In which: Q_the total resources required, equal to the area of resources
diagram.
T_time to finish the project
Step 2: Adjusting: critical tasks are fixed, the sequence and number of
adjusted tasks is uncompulsory; but it is advised to consider tasks having
large resources and long float in first place. Then adjusted tasks should be
moved in float time without affecting the average level of resources


diagram; better in the first phase and after that keep them lower than the
average a little bit.

2. Phân tích 3 nguyên tắc thiết kế tổng mặt bằng xây dựng mà anh chị cho là quan
trọng nhất? Cho ví dụ minh họa?

- 3 most important principles:
• Construction site layout must be designed so that temporary technical and
material basis provide the best services for construction process, do not
affect technology, quality, construction duration, labour safety and
environmental sanitation. For example: Manufacturing house: where
production activities are undertaken to produce materials for the project

(fabrication shop, power and water supply…); Project storehouse: to
preserve materials; House for workers: for workers daily use: canteen,
toilets…; Administration office: for Project management unit, technical and
financial management teams…; Public house and accommodation: for
public use as health care center, cultural activities…
• Reduce the cost of constructing temporary facilities by: salvaging / utilizing
parts of constructed building, selecting temporary facilities that are low –
cost, easy to dismantle and move … Temporary facilities should be located
in a favourable position to avoid wasting caused by repeated movement. For
example: minimizing construction cost of temporary house by using preengineered (prefabricated) house, movable (portable) house, or using vacant
spaces of the building…; Arrange the storehouses: Transferred storage is
constructed on traffic connection points like between railroad-road,
waterway-road.
• Designing construction site layout must follow instructions, standards of
engineering design, regulations of labour safety, fire safety and
environmental sanitation. For example: Follow QCVN 18:2021/BXD –
National Technical Regulation on Safety in Construction; Circular
16/2021/TT-BXD; Circular 02/2018/TT-BXD – Environmental Protection
for Constructions.

3. Tại sao cần xây dựng các biểu đồ tiêu thụ tài nguyên? Trình bày cách
vẽ biểu đồ tiêu thụ 1 loại tài nguyên (cho ví dụ minh họa)? (page 77)
Cần xây dựng vì:
- The intitial schedule usually does not comply with techinical requirements
and not appropriate for the production capacity, the ability of supplying
materials, machines and equipment, which can lead to adjustments of the
schedule plan. In addition to the rationality assessment of the schedule
plan, resource charts help define exactly the amount, types, strength and
order using main materials and machines. These data are also the basis to

ensure the supply of materials and machines, and preparation work for the
construction phase.
- The charts are often for resources including labour (general labour chart,
for each job), materials, machines, equipment, investment capital, etc.
Cách vẽ biểu đồ:
- Material charts are established for main materials accounted for large volumes

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over time (days) such as sand, stone, cement, brick etc. In particular, assembly
works can be made in detail through each hour of a shift, each segment, and
each area or machine standing position. Generally, material charts show figures
about ultizing, transporting and storing materials, etc at the same time.
Structure of material charts includes: Daily usage charts, Accumulative usage
charts, Traffic density charts, Continuous traffic density charts,
Discontinuous traffic density charts, Storing-material charts
(có thể bỏ phần trên này)
Method to establish storing-material charts.
When the delivery and supply of materials are continuous with a constant
number of verhicles, steps to establish the chart explained as follows:
• Establish a daily usage chart (1) obtained from the schedule plan.
• Establish an accumulative usage chart (2) analyzed from (1) by
accumulating amounts of materials used over time.
• Based on the storing-material norm over time, establish an accumulative
storageusage chart (3) by moving the chart (2) to the left a distance equal to
the storage time.
• Draw a traffic density chart (4) in the form of pencil of rays corresponding

to the number of verhicles based on transportation types, ability, and
distance.
• Select the ray with greatest angle and closest to the angle of (3) to the main
delivery road (5) in the traffic density chart (4). The intersection point
between the (5) with the axis x’ parallel to the horizontal axis, which goes
pass the largest ordinale of the line (2), is the end time of the delivery.
• Draw a storing-material chart (6) at the bottom of the horizontal axis
contrast with the above charts. Its value at each point is the difference
between the main transport road (5) and the accumulative usage line (2)


4. Trình bày khái niệm dây chuyền cơng trình đơn vị? Theo anh/chị, dây
chuyền cơng trình đơn vị thi cơng nhà nhiều tầng có thể gồm những
dây chuyền chun mơn hóa nào (the master schedule – CPM
networks)? Trình bày hướng phát triển của các dây chuyền CMH này
và thể hiện trên biểu đồ tiến độ. (Page
5. Theo anh/chị, trong trường hợp nào phải điều chỉnh biểu đồ nhân
lực? Trình bày và giải thích các cách để điều chỉnh biểu đồ nhân lực?
Điều kiện áp dụng các cách đó?
We need optimise the labour chart because:
- There are cases in which labour demand are unevenly distributed
overtime, sometimes exceed (or being utilized improperly) the limitation
of practical providing.
Adjustment measure:
- Problem 1: Allocating resources and ensuring the project’s finish time 
Burgess algorithm


- Problem 2: Shortening project’s finish time as well as respecting
resources’ condition  Kelly algorithm

When need to fix fast and relatively, quick adjustment method is used:
• Step 1: Translate network diagram into time axis or bar chart (based on
its complexity). Determine the average of resources Rtb : Rtb = Q/T
In which: Q_the total resources required, equal to the area of resources
diagram.
T_time to finish the project
• Step 2: Adjusting: critical tasks are fixed, the sequence and number of
adjusted tasks is uncompulsory; but it is advised to consider tasks
having large resources and long float in first place. Then adjusted tasks
should be moved in float time without affecting the average level of
resources diagram; better in the first phase and after that keep them
lower than the average a little bit.
Condition to apply Quick adjustment method:
• Allocating resources and ensuring the project’s finish time
• Shortening project’s finish time as well as respecting resources’
condition
6. Khi thiết kế, bố trí khu văn phịng làm việc, nhà ở công nhân trên
công trường xây dựng cần xem xét đến những yếu tố gì? Hãy giải
thích?
- Design of Temporary housing consists of following basic contents: calculation
of site manpower, calculation of area of all types of temporary houses, selection
of house structure, and comparison of economic options
a) Calculation of site manpower
Site manpower composes of different groups of manpower, the number of
manpower changes according to construction schedule. For this reason, one of the
most important requirements to calculate the number of temporary houses is to
calculate the Site manpower. Manpower structure consists of 7 main groups as
following: Group of Main workers (N1), Group of Supporting workers (N2),
Group of technical staffs/engineers (N3), Group of administration and
commercial staffs (N4), Group of supporting staffs (N5), Dependant personnel

(N6), Staffs for coordination of general activities (N7)

b) Calculation of Temporary house area
Calculate demand of house area depending on manpower number of each group
and norm of people in Temporary house:
Fi = Ni × fi


With Fi_demanded area of temporary house i type;
Ni_number of people for temporary house i type;
fi_norm for temporary house i type, refer to tabulation.

c) Selection of Temporary house type
Depend on quality requirement to select:
Temporary house of high quality: clinic, school…use fixed “one structure”
Public house, staff house, management house…use pre-engineered structure.
WC…use movable type
d) Temporary house must satisfy the sanitation and safety regulations: Follow
QCVN 18:2021/BXD – National Technical Regulation on Safety in
Construction; Circular 16/2021/TT-BXD; Circular 02/2018/TT-BXD –
Environmental Protection for Constructions.

7. Mục đích lập phương án Tổ chức thi cơng? Nêu và giải thích các căn
cứ để lập phương án Tổ chức thi công? (Construction management
plan) – Page 19
Mục đích: SGT tổ chức thi công xây dựng trang 6
Căn cứ: SGT tổ chức thi công xây dựng trang 12
8. Định nghĩa dây truyền chuyên mơn hóa nhịp bội? tại sao phải cân
bằng dây chuyền? Giải thích phương pháp cân bằng dây truyền theo
nhịp nhanh, chậm và hiệu quả sau khi cân bằng dây truyền là gì

- Specialised production line with irregular rate is that the operational rate
of component line is unchanged, rates of different lines are different.
- We need to balance the rate of production line beacause:
• Reduce the organizational interuption
• Maintain the regular (unchanged) feature of production
• Create stability, harmonization
• Shorten the duration of component line
- Quick balance:
• Make all the Component lines to have the same rate by adding more
working crews to the component line having multiple rate working
simultaneously at intermittent segments.
• Duration/time can be shortened. The component line is more effective
(T2>0)
- Slow balance:
• When the resource is limited and time shortening is not required, all
component lines are directed to have the same rate which is equal to
the rate of the slow component lines. Now the interruption is
compulsorily to be appeared in the rate of the quick component lines
• Duration/time can be shortened. The component line is more effective
(T2>0)


9. Mục đích của việc lập tiến độ thi cơng? Nội dung của tiến độ thi
cơng? Trình bày và giải thích các cắn cứ lập tiến độ thi cơng?
(The purpose of construction progressing planning? The content of construction
progressing planning? The basis of construction progressing planning?)
- The purpose:
• Defines the sequence and duration for tasks, processes or work items,

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including requirements for resources and the use of such resources in
sequence to finish scheduled plans
• Be a form and a tool, describes the development of construction in time and
space, together with supply requirement based on construction and project
management.
The content:

10.Trên SĐM mũi tên, anh/chị có thể thấy được các thơng số tiến độ
nào? (cho ví dụ) Gián đoạn giữa các cơng việc được thể hiện như thế
nào trên SĐM mũi tên?
- Parameter of network diagram:
• Duration of task (tij): means time to complete task as scheduled
• Early start of task (): is the earliest time that a task can start without

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affecting previous activities.
• Late finish of a task (): is the latest time that a task can finish if it has late
start.
• Toal Float (~ Total Slack) (Dij): is the amount of time available to extend
duaration of activity or to alter its start (finish) milestones without affecting
total time of project.
• Particular Float (dij): is the amount of time by which an activity can be
delayed or extended without affecting the early start date of any subsequent
activity.
• Longest duration (h): Number of previous event of the longest path
For example:

Determine the task 1-2:

• Duration of task (tij): t12 = 3
• Early start of task (): =3
• Late finish of a task (): =3
• Toal Float (~ Total Slack) (Dij): D12=0
• Particular Float (dij): dij=0
• Longest duration (h): h2=1
- There is interuption between tasks, we demonstrate by Imaginary task

11.Trình bày các cơ sở để xác định được mối quan hệ giữa các công việc
khi lập tiến độ thi cơng xây dựng? (nêu ví dụ?)
12.u cầu an tồn khi bố trí, vận hành cần trục tháp trên công trường
thi công nhà cao tầng?
- Standing position and mobilizing way of cranes must ensure the safety of
cranes, buildings, workers on the site, ease the installation and dismantlement.

- Standing position:
• Distance from center axis of crane to the building edge:
+ Tower crane moving on rails:

+ Fixed tower cranes:

When constructing underground part with using tower cranes, it is necessary
to check safety conditions for the foundation hole.


- When operate the crane:
• Require personal protection equipment (PPE) for those working on or
around a crane

• Using mobile crane hand signals
• Define the moving path of cranes to obtain the basis to design temporary
facilities, arrange materials and components

• Using crane safety signs
• Crane safety training

13.Nêu tóm tắt 3 nhóm tài liệu cần có khi lập tổng mặt bằng xây dựng.
a) General documents
Instructions for designing construction site layout:design regulations &
standards, engineering instructions and temporary facility design. Standards
of safety, environmental sanitation, regulations, and drawing symbols, etc.
b) Particular documents for each specific building
The plan for the status of building site.
Topographic map, ordance survey map, geological and hydrological
documents
Master plan of buildings, infrastructure system of buildings
Drawings about construction technology (planned in the files of construction
organization design and construction management plan), construction
schedule plan.
c) Specific survey documents for each building (if necessary)
Documents about local economy and society.
Ability of exploiting or supplying local materials.
Ability of supplying local construction equipment.
Ability of supplying local electricity, water, communication, etc.
Ability of providing local manpower, health services, etc.
14.