Baldor GLC50, GLC35, GLC80, GLC125 manual Approximate Load Bearing Capacities of Various Soil Types

Table 2-1 Approximate Load Bearing Capacities of Various Soil Types

Soil Type			Safe Bearing Capacity
	lb per ft2			kilo Pascals
Hard Rock – Granite etc.	50,000	– 200,000		2,395	– 9,576
Medium Rock – Shale etc.	20,000		– 30,000	958 – 1,436
Hardpan	16,000		– 20,000	766	– 958
Soft Rock	10,000		– 20,000	479	– 958
Compacted Sand and Gravel	10,000		– 12,000	479	– 575
Hard Clay	8,000	– 10,000		383	– 479
Gravel and Coarse Sand	8,000	– 10,000		383	– 479
Loose, Medium and Coarse Sand	8,000	– 10,000		383	– 479
Compacted Fine Sand	6,000		– 8,000	287	– 383
Medium Clay	4,000		– 8,000	192	– 383
Loose Fine Sand	2,000		– 4,000	96 – 192
Soft Clay	2,000				96

Table 2-1 shows approximate load bearing capacities for various types of soil if the actual load bearing capacity of the soil under the foundation is not known.

Caution: Check the local building codes for load bearing capacity requirements.

Caution: If the soil is subject to freezing and thawing, the foundation must be extended below the frost line. Check the local building codes.

SReinforce the foundation with No. 8 gauge steel wire mesh placed horizontally on 6in (150mm) centers. As an alternative, use No. 6 re–bars on 12in (300mm) centers horizontally. Minimum cover over the bars should be 3in (76mm).

SSuggested concrete mixture by volume is 1 part cement, 2 parts sand, and 3 parts aggregate. Maximum slump of 4in (100mm) and a 28–day compressive strength of 3000 psi (20,600 kPa).

SThe size of the bolts holding the sub–base to the foundation should be sized to fit the mounting holes shown on the Installation Diagram.

SThree–inch (76mm) iron pipe sleeves should be placed around the bolts in the foundation to allow for any mislocation of the bolts after the foundation hardens. “J” or “L” type bolts are recommended for the foundation bolts.

SAfter the foundation is cured and the genset is located, the sleeves are filled with grout. Figure 2-5 shows a typical foundation installation.

Figure 2-5 Typical Foundation Installation

2-8 General Information MN2408