Characteristics of the materials

The materials used in the construction of micropiles are grout or mortar and a frame, composed of corrugated steel bars or steel pipe.

CIMENTATEC often uses cement grout or mortar depending on the characteristics of each project. The frames used are always threaded tongue and grove steel pipe with a high elasticity limit.

Where cement grout is used, it should comply with the following standards:

• The type of cement used will have a minimum resistance class of 42.5 N.
• At 28 days the characteristic strength of the grout should exceed 25 MPa.
• At 7 days the characteristic strength of the grout should be equal to or exceed 60% of the required resistance of 28 days.
• The water/cement ratio should be between 0.4 and 0.55, with the ideal mix used of 0.5.

If mortar is used, it should meet the following standards:

• At 28 days the characteristic strength should exceed 25 MPa.
• The minimum cement content should be 375 kg/m3.
• The water/cement ratio should be less than 0.6.
• The grade of the aggregate should comply with: D85 = 4 mm and D100 = 8 mm.

The steel pipe used by CIMENTATEC meets the following standards:

• N-80 type steel with an elasticity limit = 5620 kg/cm2 and a breakage point = 6900 Kg/cm2.
• Diameter tolerance of ± 1%.
• Thickness tolerance of ± 12%.
• The most widely used commercial diameters are shown in the following table: