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Sheet Piling Water tightness Sealant

From the perspective of water sealing property, the most optimal state of interlock of steel sheet pile is gap-free engagement. But from the perspective of erection, some certain margin shall be reserved during manufacturing; therefore, water exclusion effect shall be realized through the sealing of interlock and the penetration depth of pile so as to ensure foundation pit safety. 

Saturation line

Like hot-rolled steel sheet piles, the water sealing effect of WR series steel sheet piles is associated with various factors. Water sealing of steel sheet pile is classified into natural sealing and artificial sealing: 

(1) Natural sealing means that interlock gap is blocked using suspended matters or soil, sand and other fine-particle substances at back side of steel sheet pile as shown in the figure below: 

(2) Artificial sealing could be performed before or after the sinking of steel sheet pile

Materials for artificial water sealing are applied inside interlock before the driving and erection of steel sheet pile in the following ways: 

① Mixture of ordinary asphalt, butter and sawdust etc. is uniformly applied to interior of interlock; 

② Apply water-swollen sealing material uniformly into interlock and seal both ends and exterior of interlock and then remove the sealing during piling at construction site. This method has remarkable effect; 

③ Various super artificial sealing 

Moisture-hardened liquid-state water sealing material with special resins from polyurethane and ethyl formate families as major component is directly poured into the interlock of steel sheet pile and dried naturally; this material swell gradually after being in contact with water and then  plays the role of water sealing. 

④ Magnetic sealant

This is a kind of soft rubber strip with super-strong magnetic force there-inside, of which the shape could be designed according to the shape of interlock. After the completion of construction, sealing strip is embedded into interlock connecting area of steel sheet pile at water surface. This sealing strip has remarkable effect on shoring foundation pit with small change of water pressure as shown in the figure below: 


Magnetic sealing strip 

In all conscience, besides the vertical interlock sealing, water sealing shall be provided at steel sheet pile connecting area, the connection points between steel sheet pile and ring strip (or base plate) and between steel sheet pile and pull rod (anchor rod) etc. by welding of waterproof gasket or water stop (seal coat) or other technical measures for waterproof protection of underground works or node structure measures. 

Water sealing effect of steel sheet pile under different conditions may vary. Here are some examples:   

(1) Factors relating to steel sheet pile  

① Corrosion degree of steel sheet pile; 

② Bending and warping of steel sheet pile 

(2) Construction environment related factors

① Water pressure; 

② Water quality (turbidity); 

③ Soil conditions (buried foundation and soil & sand at back side); 

④ Degree of plugging of interlock by soil and sand 

(3) Construction related factors  

① Engagement state of steel sheet pile; 

② Inclination and revolution of steel sheet pile