SL3 (PMF=-0.6; -0.8 for buildings of 8-20 stories): Soft to medium stiff clays and sands, characterized by 30 ft. or more of soft to medium stiff clay with or without intervening layers of sand or other cohesionless soils.

For the SL3 profile, a PMF of -0.8 is employed to account for resonance of buildings in the 8- to 20-story range. Because it is anticipated that wood (W), light metal (S3), tilt-up (PC1), or unreinforced masonry (URM) buildings will not be higher than eight stories, the PMF of -0.8 does not apply to these building types.

4.14 Comments Section on Data Collection Form

This last section of the form is for any comments the inspector may wish to make regarding the building, occupancy, condition, quality of the data or unusual circumstances of any type.

4.15 Examples

To illustrate the RSP, a discussion of the evaluation process, including examples for an entire city block, is included here. Figures 4-21 to 4-35 provide example prefield data, Data Collection Forms, and photos.

The Sanborn map (see Figure 3-1) was used as the main pre-field data source for this block. Tax assessor's file data (Figure 4-21) were used to supplement the building age and size information from the Sanborn map. Before the field survey, the following pre-field data were transferred to the data collection forms:

1. The construction type and year for some of the buildings were obtained.

2. The number of floors was indicated by the map. This will need to be verified in the field, as floors are sometimes added later. A common scenario is the splitting

of a tall first floor of an older building into a short ground floor and a mezzanine floor.

3. Building area was taken from the tax assessor's file. If the building area information is not available from the tax file, it may be estimated using the Sanborn map and approximate measurement in field. Because the map indicates the size of the land parcels, data from the map can be a useful supplement to field estimates.

4. The building shapes were sketched on the survey forms before the field survey because pre-field sketching from a map will generally produce much better results. This configuration information will also be helpful in the field for understanding the entire building as seen from the street. This is especially valuable when access between buildings is not possible. The following is a step-bystep record of the evaluation process for each building on the example block.

540-546 Main (Figures 4-22a, 4-22b)

1. The number of floors is found to be 11 instead of 10 as indicated on the Sanborn map, because a mezzanine was added.

2. No date of construction was indicated on the Sanbom map, but the assessor's file indicates that it was constructed in 1913. The architectural style of the building is consistent with this date, meaning that the building has not gone through major renovations.

3. The window openings are very large and in a grid pattern, indicating that a frame structure is probably used. It is also possible that braced frames or shear walls are not visible, although shear walls are unlikely in a building of this

vintage. The rear wall can be considered as an unintended shear wall, although it has window penetrations. The rear wall reveals concrete pour marks, indicating that it is a concrete wall. Hence, URM infill is ruled out, and the building can be considered to be one of five possible types (S1, S2, S4, C1, C2).

4. The comice ornamentations are large and probably of terra-cotta construction. This constitutes a non-structural falling hazard.

5. The rear wall is a concrete wall with a few windows and is substantially stiffer than other walls. This, in combination with the wedge shaped floor plan, will result in torsion problems.

6. The building is taller than eight stories and is therefore a high-rise.

550 Main (Figure 4-23)

1. The Sanbom map indicates that this is a concrete structure. From the assessor's file, the date of construction is 1908. Looking at the building, the side walls appear to be nearly 18 inches thick. This wall thickness indicates that the structure probably has URM infill walls.

2. The building has a large comice on both street facades. However, this cornice appears to be constructed of wood, and therefore not considered as a falling hazard.

554 Main (Figures 4-24a, 4-24b)

1. No date of construction was indicated on the Sanborn map, but the assessor's file shows that the original date of construction is 1907.

2. The construction type was also not indicated on the Sanborn map. However, the building has thick side

walls (see Figure 4-24b), indicating that masonry was probably used. Because this building is at least 70 years old, the masonry would not be reinforced. There is also an indication that a steel lintel was used to span the large window opening, which is typical of URM construction. This building, then, can be a URM structure or a URM infill.

560 Main (Figure 4-25)

1. A mezzanine level has been added to an original three-story building.

2. The Sanborn map indicates that this building was built in 1906 and is consistent with the inscription on the Broad Street facade which reads MCMVI. The Main Street facade clearly has been renovated. The new metal facade hides the original elevation.

3. The Sanborn map indicates that this is a concrete-frame building. From the side of the building, one can see the concrete pour marks. In the longitudinal direction, the solid concrete walls will act as shear walls. However, the frame structure in the transverse direction is apparent.

4. The irregular shape can be seen on the Sanborn map.

5. There is a potential pounding problem between this building and its neighbor, because the floor levels of these two buildings are offset by several feet and there is no space in between the buildings.

562-566 Main (Figure 4-26)

1. The Sanborn map shows that this building is a concrete-frame structure built in 1923. This is consistent with the appearance of the building, as it has many window penetrations on all sides.

2. There is a potential pounding problem

with the neighboring four-story building, because the floor levels of the buildings are offset by several feet and there is no space in between the buildings.

3. The building has masonry comice and veneer that may be considered as nonstructural falling hazards.

570-574 Main (Figure 4-27)

1. The Sanborn map does not indicate the original year of construction, but the assessor's file shows that it was constructed in 1922. At first glance, this building seems to have been built in the 1960s. Upon closer inspection, the side walls reveal concrete pour marks, which reveal that the building was built before the 1960s. The building age is also consistent with the fact that this building is a low-rise within a major downtown area. A newer building would probably be taller.

2. The Sanborn map indicates that this building is a reinforced concrete structure. From the shape of the building, the long solid walls are probably shear walls in the longitudinal direction. For the transverse direction, no solid wall can be detected from the building exterior. The building is probably a frame structure in the transverse direction. The possibility of being a URM infill structure is ruled out because of the presence of a concrete wall. This building is finally scored as a concrete frame (C1) as this is the weaker of the two possible systems.

576-580 Main (Figure 4-28)

1. The Sanborn map indicates that this is a reinforced concrete building but does not show the year of construction. The

construction date is shown on the tax assessor's file to be 1923. Looking at the architectural style one will note that it is almost the same as its neighbor, which was built in 1914, as indicated by the Sanborn map. It is reasonable that this building was constructed a few years after its neighbor.

2. The Sanborn map indicates that this building has five stories. It is determined in the field that two mezzanine floors have been added, making this a sevenstory building.

3. This is probably a concrete momentresisting frame, because three sides of the building are penetrated by many windows. Because one wall is solid, there is a potential torsion problem.

4. The building has masonry cornice and veneer, which are non-structural falling hazards.

582-592 Main (Figure 4-29)

1. The Sanborn map indicates that this is a steel-frame built in 1914. The possible structural systems are moment-resisting frame (S1), braced frame (S2), or steel with reinforced concrete shear wall (S4). The building is scored for all the possibilities.

2. The building has one added mezzanine floor and is 21 floors in total rather than 20 as indicated by the Sanbom map. The plan shape of the building also changes at the 13th floor from an irregular shape to a pill shape tower. Therefore, the building is a high-rise and has vertical irregularity. Because of the irregular shape, the building also has a potential torsion problem.

3. This building has masonry comice and veneer, which are non-structural falling hazards.