Rubber Dam System

Description

Along with the development of polymer synthetic materials industry, rubber dam as an innovative hydraulic structure, is composed of high strength fabric as reinforced framework and synthetic rubber which anchored on concrete foundation to form a sealed bag. A layer of stainless steel mesh or ceramic chips can be embedded in the top surface rubber layer to reduce or prevent vandal damage. rubber dam formed by inflating it with water or air through the filling and drainage pipeline. The dam crest can overflow, and the dam height can be adjusted as needed to control the upstream water level. In the dry season, the sealed bag will be filled with water or inflated with air to form a dam for retaining water to meet the water needs of industry, agriculture, and daily use. In the rainy season, discharge the water or air from the sealed bag until the dam falling down which will not influence the flood discharge of the river. With advantages of short construction period, long service life, convenient operation and maintenance, strong seismic resistance, and so on, rubber dams have been widely used in irrigation, power generation, flood control, recreation, and urban environment beautification, etc.

Main Structure
· Civil construction part
· Dam bag
· Anchoring parts
· Filling and draining (air) facilities
· Control system

Classification
According to the filled medium, it can be classified into water filled rubber dam and air inflated rubber dam.
According to the installation form, it can be classified into pillow-like rubber dam and slope rubber dam.
According to anchor form, it can be classified into bolt anchoring and wedge block anchoring.

Advantages
1. Low cost and low consumption.
It can reduce investment by 30% to 70%, and greatly save the consumption of three materials, including: saving steel by 30% to 50%, cement by about 50%, and wood by more than 60%.
2. Low operating and maintenance costs.
Moving parts require no lubrication and no painting. Works well in cold conditions without de-icing and will not seize mechanical parts.
3. The installation is fast and simple, and the construction period is short.
The installation of the dam bag only takes 5 to 15 days, the cycle is short, and the benefits are quick after completion.
4. Anti-seismic, anti-foundation settlement, impact-resistant
The dam body is made of flexible material, which is anti-seismic, impact-resistant and wave-resistant. Strong resistance to foundation deformation and good water-stopping effect. Can accommodate potential uneven settlement of the foundation
5. Simple structure
The single dam has a large span and does not require too many middle piers and other structures. It does not block water during the flood season, has sufficient collapse, and is safe for flood discharge.
6. Security
The rubber dam adopts the latest technology, which is integrally formed and vulcanized at one time. It has the outstanding advantages of consistent and stable overall performance and no safety hazards in splicing. Long-term operation without deformation; and the designed service life of the whole dam bag is 10-15 years longer than that of the rubber dam.
7. Appearance
The color and shape are beautiful, and it is used in the construction of river landscape, which is beneficial to create waterscape and beautify the environment.

Application
· Retain water.
· Adjust the water level.
· Irrigation.
· Generate hydro-electric power.
· Control flood.
· Tidal barriers.
· Control water.
· Shipping.
· Increase reservoir capacity.
· Industrial and agricultural production.
· sewage treatment system
· Ecological protection.
· Develop water entertainment and tourism.
· Urban environment beautification.

Comparison and Choose

1) Rubber dams have many uses. We can check the comparison below and choose Air Filling Rubber Dam or Water Filled Rubber Dam according to different uses and specific conditions.

Item	Water Filled Rubber Dam	Air Filling Rubber Dam
Outside air temperature	The internal water of rubber bladder would be frozen in cold temperature	The internal pressure would change when temperature changes greatly
In hot Area	The internal water could reduce the outer surface temperature of rubber bladder and prolong the rubber dam service life	The internal pressure would be very high
Circumference length of rubber bladder	longer	shorter
Loading concrete foundation	Longer with high cost	Shorter with lower cost
Max. Overflow height	50% of dam height	30% of dam height
Stability of rubber bladder during operation	Stable	Would vibrate. The vibrasion will be reduced if there is deflector design
Inflation and deflation time	Longer time	Shorter time
Inflation and deflation pipe	Pipe diameter is bigger	Pipe diameter is smaller
Application in hydraulic power station	Could adjust the upriver level according to adjust dam height	Could not adjust upriver water level
Build in spillway of hydraulic power station	Could not if the spillway is not horizontal	Could

2) Air inflated rubber dam data (Air); Water inflated rubber dam data(Water).

Height(m)		Pressure Rate(in/out)		Radial Strength(kN/m)		Thickness (mm)		Safety Factor
Air	Water	Air	Water	Air	Water	Air	Water	Air	Water
1.0	1.0	1.0	1.50	5.00	5.00	10	5.5	45.00	25.60
1.5	1.5	1.0	1.50	11.25	11.25	10	6.2	20.00	17.78
2.0	2.0	1.0	1.40	20.00	18.00	10	6.8	13.50	13.33
2.5	2.5	1.0	1.40	31.25	28.13	10	7.3	11.52	11.38
3.0	3.0	0.9	1.30	40.50	36.00	12	7.9	11.11	12.22
3.5	3.5	0.8	1.30	49.00	49.00	12	8.5	10.10	11.43
-	4.0	-	1.25	-	60.00	-	10.2	-	12.00
-	4.5	-	1.25	-	75.94	-	11.1	-	11.06
-	5.0	-	1.20	-	87.50	-	12.7	-	11.65

Physical and Mechanical Properties Data

Item			Outer layer	Middle layer, inner layer	Cover rubber sheet
Tensile strength at break		MPa	14	12	6
Elongation at break		%	400	400	250
Permanent deformation at break		%	30	30	35
Hardness (shore A)			55-65	50-60	55-65
Brittleness temperature		°C	-30	-30	-30
Hot water aging (100 °C × 96 h)	Tensile strength at break	MPa	12	10	5
	Elongation at break	%	300	300	200
Hot water aging (70 °C × 96 h)	Tensile strength at break	MPa	12	10	5
	Elongation at break	%	300	300	200
	Volume expansion ratio	%	15	15	15
Wear loss (akron)		cm3/1.61 km	1	1	1.2
Ozone aging: 10000 pphm, temperature 40 °C, stretching 20%, no cracking		min	120	120	100
Flexibility, no cracking		Ten thousand times	20	20	20

Installation

· Mark dam axes and centerline on pre-concreted foundations.

· Install embedded anchor bolts and plates.

· Install nozzle and pipes before concreting.

· Pour the concrete.

· Cut and punch holes on rubber bladders for anchor bolts.

· Anchor rubber bladder and clamping plates. For inclined rubber dam, install the inflated rubber dam from lower reaches to upper reaches and land wall. As to pillow-like dam, start from stop-ends at the corner of the dam, and then fasten the upper and lower reached of the rubber body.

· Retorque the anchor bolts and seal the bladder.

· Complete commissioning test.

Service Support

1)Whole Technological Design

We determine reasonable plans and selections by conducting more systematic laboratory tests, semi-industrialization tests and theoretical analysis calculations and adopting appropriate methods in light of the actual problems faced by customers. And it determines specific parameters through laboratory tests and semi-industrial tests.

2)Project Construction

We can provide customers with integrated project services for its perfect project management system and experienced high-quality team and can also provide customers with its best services in achieving the ultimate project goal by carrying out the management work on the project quality, schedule, safety, cost, procurement, information files, organization and coordination etc. according to customer’s contractual documents.