Cấp phối đá dăm_ Tiếng Anh

Group 1:

1. Vũ Tuấn Tú
2. Lưu Quang Vũ
3. Phạm Văn Minh
4. Đỗ Phương Nam
5. Lê Ngọc Linh
6. Nguyễn Ngọc Trịnh
7. Nguyễn Thị Phương Anh
8. Nguyễn Thị Phương Linh
9. Lê Trung Chất
10. Nguyễn Văn Cương


Construction and acceptance stabilized aggregate base course procedures

1. General
rules

4. Inspection,

2. Technical

acceptance

requirements

3. Construction
technology

1. General rules
1.1. Field of application

1.1.1. This Regulation stipulates the technical requirements for materials, technical and laboratory equipment used in the wet cleaning process. Type of
filling (CPDD).

1.1.2. Slabs of low-level material are as follows: the level of beeswax, the dressing, the breasts, the breasts and the breeds and the breeds that have been
bred by high quality ... not subject to the provisions of this Regulation.

1.1.3. This procedure replaces the "Criteria for the manufacture and assembly of rubber sheets in accordance with the method of installation" 22 TCN 25298.


1.2 Definitions and terminology

1.2.1 Graded Aggregate is a mixture of granular rock material with granular composition that complies with the principle of continuous grading, The symbol is
CPDD.
1.2.2. CPDD using a network is divided into two types: CPDD type I and type II.
CPDD type I: is the level of coverage of all probable cases - estimated from the statute
Declare.
CPDD type II: is a sealant that is applied from the opening or bottom of the sheet, where it is less than 2.36 mm in thickness, which may be a naked prison void.
The liquids do not absorb 50% of the CPDD. When CPDD is estimated to be 9.5 mm in diameter, it is estimated that 75% of the total surface area is covered by
two planes because it is large.

CPDD type I

CPDD type II


1.3 Scope of using different types of central offices
1.3.1 CPDD type I: is used as the upper (and lower foundation on the basis of technical and economic considerations) of soft pavement structure with surface

layer A1 or A2 according to 22TCN 211-06. The upper foundation under 22TCN 274-01.
1.3.2 CPDD type II: shall be used as the substructure of the pavement structure with A1 surface layer and as the foundation for A2 or B1 surface layer 22TCN
211-06 or under foundation 22TCN 274-01 .

2. Technical requirements for Graded Aggregate

2.1 Constituent of Joint Stock Company
2.1.1. The composition of GA is stipulated in Table 1.


Tab 1. Component seed of aggregate macadam

Size screening surface

Proportion percentage % by weight

 

D =

square (mm)

max

100
 

37,5

25

-

9,5

4,75

0,425

0,075

 

- 64

25 - 40

 

12 - 24

 

13 - 27
 

2 - 12
 

 

30 - 45
 

 

 

39 - 59
 

 

 

58 - 73
 

34 - 54

2- 12
 

90 - 100
 

49

7- 19
 

-

100

- 83

 

 

 

 

 

15 - 30
 

 

- 90

24 - 39

2,36
 

 

 

 

 

 

 

67

39 - 59
 

100

 

 

max = 19 mm

 

79
 

 

D

 

 

58 - 78
 

 

-

 
 

 

 

19
 

 

 

 

 

max = 25 mm

95- 100
 

 

D

37,5 mm

50
 

 

 

2 - 12
 

 


2.1.2. The distribution of the common stock (according to the most common name of Dmax) shall be based on the coding of the design and shall be included only in the
application form and the technical specifications of the works:

A. Dmax = 37.5 mm rated for dip galvanized;

B. Dmax = 25 mm grade suitable for the above layer;

C. Dmax = 19 mm, suitable for both sides and up to the height of the joints in the substrate.

2.2 Indications of management of the contents of this packet
Indicators of essential ingredients of CPDD are specified in Table 2.


Tab 2. Targets Physico-mechanical require of material CPDD
 

aggregate macadam

Method

 
 

TT

Target technology

 

 

  

 

  

 

 
Lo¹i I

 

 

Lo¹i II

 

 

experiment
 

 

  Wear and tear Los-Angeles of aggregate
1
 

2

 

 

 
 

(LA), %

 

Index Load capacity CBR in tightness

 

 

≤ 35
 

≤ 40
 

22 TCN 318-04
 

 

No

 

≥ 100

 

 

22 TCN 332-06

 

 

K98, drench 96 hours , %

3

 

Limit run (WL), %

 

≤ 25

≤ 35

AASHTO T89-02 (*)

 

4

 

index plastic (IP), %

 

≤6

≤6

AASHTO T90-02 (*)

 

 

index PP = index plastic IP

≤ 45

≤ 60

 

5
 

6

 

X % measure
 

 
 

come through screen 0,075 mm

 

 

content bead Flat, %

 

7

 

 

≤ 15

 

tightness Compaction (Kyc), %

 
  

Ghi chó:

 

 

 

 

 

 

≤ 15

≥ 98

 

 

 

 

 

regulations

TCVN 1772-87(**)

 

22 TCN 333-06

 

≥ 98

 

 

 

 

 

 

 

( Method II-D)

 

(*)

 

 
 

Limit run, limit flastic determined by experiment with grain compotision passes through the sieve

 

0,425 mm.

 

 

 

 

 

 

(**)

 

 

seed rhombus is seed is depth or width less than or equal 1/3 long ;

 

 

Experiments were conducted with particle sizes larger than 4.75 mm

 

 

 

 

 

 

 
 

 

 

 

 

 

 

 

 

 

 

 

 

 


*Contact Reality
- Advantage:
+ intensity pretty high Eđh = 2000 - 3000 daN/ cm2
+ Equivalent Stable water.
+ price reasonable.

- Disadvantage:
+ Horizontal thrust cream.

+ request High material demand produce in enterprise with chain technology modern Should be High price.
+ easy to abrasive below action of load wheel should be Dust generation when sky dry onion, it rains component binder soil,
badigeon undergo wash make rock undergo burst out create to pot hole make pavement tenuity flat.
+ coefficient cling Between wheel androad surface small.
+ intension Much reduced when damp (Special is aggregate macadam Type 2 )


3. Construction technology subbase canal by aggregate macadam.


3.1 Construction preparation.
a. Preparation roadway :
- Span, drive ascertain ambit building of pavement.

- Roadway ensure to get building right size Vertical (latitude, depth), right altitude, crossfall, tightness and Flatness.
If condition then edgestone: Broad 10÷15 cm
H = h + (10÷15 cm) and not calculate into breadth roadway.

- Base course must be building right instruction and must be acceptance before make gradation.

- When rip-rap energize pavement old if pavement old pawn and even and flat then must clean pavement then rip-rap new up. If pavement old
much pot hole and downy then mix before rip-rap new.


b, Preparation of materials and construction equipment:
- Prepare all major construction materials: sufficient quantity and quality assurance.
- The aggregate must be processed and assembled in the material dumps.
- Experimental results of mechanical parameters must be submitted to the site.
- The mix must be mixed before the dredge.
- Every 3,000m3 of material at the mine must take samples to check the quality.

- For every 1000m3 of material transported to the site must take samples for quality inspection.

* Prepare spreaders, levelers, all kinds of trucks, transport vehicles, moisture control equipment, thickness, tightness testers, moisture, ...

c. Pilot implementation:
- Each test section is 50m long.
- From the experimental data to determine the maximum dry density and best moisture content of the mixture (22TCN 333-06 method II-D).


3.2 Requirements for construction of road foundation by consumer materials
*Transportation:
- Use dump trucks to transport materials. Before pouring CPDD into the car, water the tank and the CPDD.
- Use manual bucket excavator on the car, not to hand, when the stock to ensure the fall of the stock market to the body of 0.5m (avoid
stratification).
- When returning home, the moisture content should be suitable to level and level up W0 ± 1% moisture content.
- CPDD to the site is best to use spreaders for spreading. If not using spreaders, then use the leveling machine to ensure that the level of
material is not stratified, the distance to pile as short as possible → 1 car pours into 2 ÷ 3 piles (distance ≤ 8 - 10m).


*Attention:
- If the material is below the optimum moisture content of the material, additional water should be irrigated with rainwater sprinklers and no fine
water washed off. It is advisable to incorporate the addition right during the spreading, compacting with the spray fog mounted attached.
-If the humidity is above the optimum moisture range, it must be spread out to dry before rolling.
- For every 200m3 of material or 1 construction work, one sample should be tested: grain composition, moisture content.

b, Work to distribute local government
- With foundation layer, gravel material is used only screed machine used. With the subsoil, a spreader or leveler can be used.
- Water to stick before spraying.
- Make a curbstone or CP spread 25cm wide on each side.

- Regularly check the gravity moisture before spreading the stone.
- Only sprayed by a stone paving machine if approved by the supervision consultant, the foundation can be spread by a leveling machine . Soviet system sprayed right Kr=1.3.
- Make sure the thickness , flatness , horizontal slope design.
- The thickness of each layer must be leveled not more than 18cm for the foundation and 15cm for the upper one and the thickness of each layer shall not be less than three
times the maximum particle size.
- in order to ensure leveling on the entire width of the foundation.
- If the width of the pavement is large use scattered dirt.
- Using multiple spreaders simultaneously, the machine must be spaced 10-20m apart.
- Using a spreading machine to spread , spread enough width should proceed immeditaely.
- Between patches the joints must be treated.
- It is necessary to regularly check the elevation , flatness , horizontal slope , vertical slope humidity and harmonics of the macadam material during the spreading process.
- If a stratified mixture is to be found , replace it with a good one.
-It is necessary to leave 5% of grading to offset later.


c. Leveling work:
*Request:
- If the thickness is greater than that , it must be divided into 2 layer, if spread and continue to level the layer immediately , sequence and technology as the lower layer.
- Prior to leveling , the pilot must be leveled L ≥ 50m.


* The stage:
- Preliminary leveling : use static roller 6T-8T, roller 3-4 weekly/point, speed 2-3km/h. Immediately after the preliminary flattening stage should
immediately carry out the inspection of the horizontal slope , flatness and detect the convexity of the concave , stratified to timely repair.
+If there are unusual phenomena such as cracks , ripples , buckets or discrete not tight to stop immediately to find the cause and radical and then to do
next. All of these tasks must be completed before reaching 80% of the stage
+If the filler has to be filler after the foundation has been completed , the surface of the nail bed must be plowed with a depth of a least 5cm before
offsettings.
- Flat leveling using 8-10T or 14T vibratory roller, roller 8-10 times/point, speed 2-4km/h. Then use flat tire roller 10-25 times/point, load wheel >1.5T ,

speed 2-4km/h.
- Complete flat finishing using 8-10T static steel rollers , leveling 3-4times/point, speed 2-4km/h.


- When lu must reward through wet sand dirt smooth <1mm unflatty unstable road surface.
- If there appears to be a stratification of excavation replaced with new material and then roll up.
- Make sure the backing material overlaps the material 15-20cm, the bottom 10cm from the edge, the overlap on the edge 20-30cm.
- When it goes from the edge to the heart, from low to high.
d, Complete maintenance and plastic sealing:

-

Finishing: collecting fallen materials finishing the surface layer and roadside, dredging edge.
Maintaining and impregnating resin:

+ If applied in 2 coats, the substrate must be watered and the top coat applied (not finished).
+ If gravel layer is applied on top pavement A1, A2 must be applied.
+ Quickly irrigate with 1kg / m2 of plastic resin. And spread the sand layer 2-5mm and use a roadblock brush; 9-10 kg/ m2

If transportation must be ensued immediately afterwatering, the layer should be covered
with 0.5cm x 1cm grit with a rate of 10 ± 1 kg/m2 and leveled 2-3 times/ point. At the same
time, it is necessary to arrange the maintenance force daily, such as surface drainage, swept
up rocks and leveled up the places where the phenomenon of settlement by car run.


3.3. Pilot construction

3.3.1. Request pilot construction work
a, Pilot construction must be apply for each construction in the following cases :

-

Before implement of mass construction
When have a change in the main construction equipment: bladder, spreader,…
When have a change in the source of material or GA material.

b, Pilot construction work is foundation to devise measures contexture mass constructions
to ensure that the technical requirements, performance and economics. Therefore, Pilot
construction work must project the following technological factor :

-

Material assemble diagram, functional diagram of grader or spreader;
Compact coefficient, construction layer depth;
Compact diagram.

c, All of pilot construction work must be inspected and approved by the monitoring consultant.


3.3.2 To formulate measures to organize the pilot construction.
a) The segments selected for the pilot construction must represent the construction scope of each construction tip: the type of structure of the
construction site, the longitudinal slope, the cross slope, the width of the foundation ... Usually, the minimum length of each pilot segment is 50 m.
b) Based on the requirements of construction progress, progress provides the materials, the actual conditions on the ground, about the potential
mobilization of construction equipment and the requirements referred to in 3.3.1, proceed to set up at least 2 diagram of construction technology
with pilot 2 segments were selected.
c) When establishing the diagrams construction technology pilot, must consider the full range of technical characteristics of the equipment we have,
combined with construction experience has been accumulated and the actual conditions of the device capabilities, the current market. In the diagram
the pilot construction technology, must specify the following:

-Follow the instructions in 3.2.3, the preliminary determination the thickness of each layer of material levels rubble after
sprayed or san (originally also can temporarily get the coefficient of compact
is 1.3).
-Selection and mobilization of the appropriate type of lu.
-Mapping for each lu, which specify the order number, compact and lu speed through a point, a combination of the type of lu
...
-Preliminary establishment of the ancillary jobs, steps and time to conduct the inspection, monitoring is needed to ensure the
smooth operation of the line execute and ensure the quality of works.


3.3.3 Conducting pilot implementation
a) Conduct pilot construction in accordance with the technology maps established on different pilot sections. From the results of the pilot implementation, it is
necessary to record the basic data of each step of construction have been implemented as:
- The number, volume of materials transported by means of gathering materials to the school. The distance between the piles of gravel distribution level .
- Additional watering measures to achieve the humidity during and after the san or scattered.
- High speed before and after a san or sprayed gravel distribution level materials.
- Choose the type of lu and lu served heavy construction.
- Determine the number of lu and light by preliminary close by lu types with the heavy mobilization at the construction.
- Handle the wavy, layered phenomenon, less flat and need extra compensation. (if available).
- Sequence on, out of the type of lu, lu and velocity numbers through a point.
- The results of the test determine the tightness, the construction work moisture.
- Level after completion of the work of compact Foundation class levels macadam.
- The start time, the end, weather conditions when the pilot.


b, From the confessed data, proceed assumed and correction factors as follows:
- Lay coefficient(Compact coefficient) is established lean on altitude data on the same section at the corresponding points are as follows:

 

 

CĐr¶i - CĐmb

K =

(2)

r¶i

 

 

 

 

tInthere :

 

CĐ
mb

CĐ

r¶i

CĐ

lu

-

CĐlu -CĐmb
 

 
 

 

 

Is altitude ground construction, m;

 

CPDD altitude surface layer after spraying, m;

 

CPDD altitude surface layer after compact (has reached the required tightness ), m.

 

Correlation between the number of compact and tight levels achieved
The amount of material involved in lines, distance between piles of material

c, Proceed correction pilot construction diagram, apply to mass construction.


4.Requirements for the acceptance test activity
4.1 the about sampling of materials CPDD service activity to test accepance quality materials and base course.
4.1.1 the density of sampling, essay in method be minimum.
4.1.2 the service the acceptance test activity, dimension minimum of field for sampling provisions in page 3
Page 3. requirements dimension sample at field

D

max = 37,5 mm

Maximum nominal size
 

 

Minimum sample size
 

D

max = 25 mm

 

125 Kg
 

D

max = 19 mm

 

100 Kg
 

75 Kg
 


4.1.3 the acre get represent to give plot article or section essay, audit. Belong to intent audit and specific condition, sample should adhere every demand
prime :

a. When sample at discharge door, have to guarantee to take full materials flush out, should not spill.
b. When sample on conveyor belt have to get materials on section of band conveyor, diacritical attention get close grain.
c. Do not materials at discharge door or band conveyor when catena begin fabricate, do not firm.
d. When sample materials at every pile contains, with one pile discard above body every pile make flat have caliber less than 50 cm*50cm in hollow quad
so that enough essay materials of one hole.
e. When sample materials on thin layer stones, have to hollow vertical and get materials follow depth composition.

4.2 audit acceptance quality materials.
Activity acceptance quality materials CPDD have to carry out follow every cycle.

4.2.1 cycle audit acceptance approbate source provide materials CPDD give building.