Precast framing system with concrete masonry unit infill, Indonesia

Report: 209

Building Type: Precast framing system with concrete masonry unit infill

Country: Indonesia

Author(s): Edwin Lim, Sugeng Wijanto

Last Updated:

Regions Where Found: West Java

Summary: Precast concrete system with high level risk of soft story effect.

Length of time practiced: 2005-2008

Still Practiced:

In practice as of:

Building Occupancy: Residential, 50+ units

Typical number of stories: 1–3 (PC2L: low-rise) 4–5 (PC2M: mid-rise)

Terrain-Flat:

Terrain-Sloped:

Comments:

Plan Shape: Rectangular

Additional comments on plan shape:

Typical plan length (meters):

Typical plan width (meters):

Typical story height (meters):

Type of Structural System: Precast framing system with concrete masonry infill

Additional comments on structural system:

Gravity load-bearing & lateral load-resisting systems: Slab, beam, column system

Typical wall densities in direction 1:

Typical wall densities in direction 2:

Additional comments on typical wall densities:

Wall Openings:

Is it typical for buildings of this type to have common walls with adjacent buildings?:

Modifications of buildings:

Type of Foundation: Not known, but it is usually with driven PC-pile

Additional comments on foundation:

Type of Floor System: Concrete

Additional comments on floor system:

Type of Roof System: Steel trusses (Roofing material: fiber glass)

Additional comments on roof system:

Additional comments section 2:

Who is involved with the design process?

Roles of those involved in the design process:

Expertise of those involved in the design process:

Who typically builds this construction type?

Roles of those involved in the building process:

Expertise of those involved in building process:

Construction process and phasing:

Construction issues:

Is this construction type address by codes/standards? Yes

Applicable codes or standards: Indonesian building code 2002

Process for building code enforcement:

Are building permits required? Yes

Is this typically informal construction?

Is this construction typically authorized as per development control rules?

Additional comments on building permits and development control rules:

Typical problems associated with this type of construction:

Who typically maintains buildings of this type?

Additional comments on maintenance and building condition:

Unit construction cost:

Labor requirements:

Additional comments section 3:

Patterns of occupancy:

Number of inhabitants in a typical building of this construction type during the day: >20

Number of inhabitants in a typical building of this construction type during the evening/night: >20

Additional comments on number of inhabitants:

Economic level of inhabitants: Low-income class, Middle-income class

Additional comments on economic level of inhabitants:

Typical Source of Financing:

Additional comments on financing:

Type of Ownership:

Additional comments on ownership:

Is earthquake insurance for this construction type typically available?: No

What does earthquake insurance typically cover/cost:

Are premium discounts or higher coverages available for seismically strengthened buildings or new buildings built to incorporate seismically resistant features?:

Additional comments on premium discounts:

Additional comments section 4:

Damage patterns observed in past earthquakes for this construction type: During the West Java earthquake (2009), four apartment units (built in 2005 – 2008) located in Bandung, West Java suffered severe damage at their CMU wall. In addition, some structural damage could also be found in the upper part of the columns of these apartment units. However, there was no significant damage in the fifth apartment unit constructed in 2009 (Nurjaman, 2010). The main difference between the undamaged fifth apartment unit and the rest of the units was the existence of a concrete shear wall on the ground floor. This shear wall had prevented the soft story effect in the building (Nurjaman, 2010). In contrast, severe damage could be observed in the CMU infill of the other four apartment units. This led to the belief that the CMU infill has not been strong enough to resist the earthquake lateral load. The damaged apartment units were later retrofitted by adding concrete shear wall at the lower story

Additional comments on earthquake damage patterns: The observed damages on the four building apartment units were (See Figure 4): 1. Light to severe cracking on CMU infill 2. Minor structural damage to the precast connection and the upper part of column 3. Moderate structural damage at the staircase connection to the floor

Additional comments on structural and architectural features for seismic resistance:

Vertical irregularities typically found in this construction type:

Horizontal irregularities typically found in this construction type:

Seismic deficiency in walls:

Earthquake-resilient features in walls:

Seismic deficiency in frames:

Earthquake-resilient features in frame:

Seismic deficiency in roof and floors:

Earthquake resilient features in roof and floors:

Seismic deficiency in foundation:

Earthquake-resilient features in foundation:

For information about how seismic vulnerability ratings were selected see the Seismic Vulnerability Guidelines

Additional comments section 5:

Additional comments on seismic strengthening provisions:

Has seismic strengthening described in the above table been performed?

Was the work done as a mitigation effort on an undamaged building or as a repair following earthquake damages?

Was the construction inspected in the same manner as new construction?

Who performed the construction: a contractor or owner/user? Was an architect or engineer involved?

What has been the performance of retrofitted buildings of this type in subsequent earthquakes?

Additional comments section 6: