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GEOTECHNICAL SURVEY EMERGENCY OPERATIONS CENTER

HUARAZ, ANCASH, PERU. CONCLUSIONS AND RECOMMENDATIONS. (See Annex II) 1. Ground where EOC HUARAZ will be built is located at an altitude of 3094

meters above sea level, in the region of the Peruvian Andes. The annual temperature oscillates between 24C and 26C. It has two defined seasons: tempered and dry from May to September. Its climate is called Andean Summer, being pleasant in this season of the year, with sunny brilliant days and cold nights. Rainy season is between the months of October and April, when the sun shines in the mornings and rain in the afternoons, receiving between 500 and 1000 mm. of annual rain.

2. The subsoil of the land where the inspections pits were made is

homogeneous, formed by clayed sand SC, in a semi-compact stage, beige-colored, humid and containing rocks of great sizes.

3. Based on field works, laboratory tests, profiles and stratigraphic records, it

is recommended to build the foundations on the p clayed sand SC, in the zone of inspection pits C-1, C-2 and C-3, with a foundation depth of at least: Df = 2.10m for an allowable load-bearing capacity of 1.29 kg/cm .

4. Given the ground nature and the potential magnitude of the transmitted

loads, it is recommends using a superficial foundation, such as spread footings or connected footings.

5. About the study area seismicity, it is located within the seismicity zone

Number 3 (high seismicity zone), so it must be borne in mind the possibility of occurrence of earthquakes of considerable magnitude, with intensities between VIII to IX in the Modified Mercalli Scale.

6. According to the new Technical Standard Building E-030 Seismic-resistant

Design and the predominant material of the soil of the foundation, it is recommended to take in the analysis seismic-resistant of buildings the following parameters:

a. Zone Factor: Z = 0.40 b. Soil Amplification Factor: S = 1.2 c. Period that defines the platform of the spectrum: Tp = 0.60

7. Therefore, the maximum settlement in this area is 1.49cm., this is higher

than permissible (1.00cm). Then there will be problems for settlement, so we recommend connecting the footings.

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8. We conclude that the layer of soil (stratum) that forms part of the contour

where the foundation will be placed contains severed concentrations of sulfates and slightly in chlorides, which could attack the concrete and reinforcing steel of the foundation. Therefore the kind of Cement that must be used for foundation will be Cement Type V. (See Annex II.4 - TAB.N 3)

9. SUMMARY OF FOUNDATION CONDITIONS

Kind of Foundation Connected Footings.

Stratum of support of the foundation

In the clayed sand SC

Foundation parameters Df. (m)

Qadm (kg/cm)

Settlement (cm.)

2.10 1.29 1.49

Attack of the soil against foundations

Chlorides Cl (ppm)

74.35

Sulfates SO4 (ppm)

2368.08

Foundation Cement type V

Foundation width Connected footing B=1.30 m.