Method of constructing a continuous cut-off wall and a core of a fill-type dam

In a method of constructing a continuous cut-off wall comprising the steps of:

• excavating a first wall-shaped pit in the earth;
• introducing bentonite slurry into the pit being excavated;
• inserting a tremie pipe into said pit;
• inserting through said tremie pipe into said wall-shaped pit an impermeable material by replacing said mud water to form a first cut-off wall segment;
• and
• following said first cut-off wall segment thus constructed, constructing a second cut-off wall segment in the same manner as said first cut-off wall segment, said second cut-off wall segment being positioned adjacent to an end of said first cut-off wall segment so as to connect and form a continuous extension of said first cut-off wall segment;
• and
• constructing each subsequent cut-off wall segment in like manner one after another so as to form a continuous cut-off wall in the earth, the improvement wherein said impermeable material comprises at ambient temperature a cement bitumen concrete of a cold-setting property comprising cement 80-250 kg/m.sup.3, fine aggregate 600-1000 kg/m.sup.3, coarse aggregate 800-1200 kg/m.sup.3 and bituminous emulsion 200-400 kg/m.sup.3, or a cement bitumen mortar of a cold-setting property comprising cement 200-800 kg/m.sup.3, fine aggregate 300-1500 kg/m.sup.3 and bituminous emulsion 300-900 kg/m.sup.3.