Residential Structural Design Code

4/3/2014. 1. NATIONAL STRUCTURAL CODE FOR HOUSING (NSCP 3). Residential. Structural. Design Code. By: MIRIAM LUSICA-TAMAYO, M.S.C.E., F. ASEP. ASEP Im...

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4/3/2014

NATIONAL STRUCTURAL CODE FOR HOUSING (NSCP 3)

Residential Structural Design Code

REALITY CHECK * There are many non-engineered houses, existing and still being built. * Even engineered houses are “non-compliant” with prevailing building codes.

By: MIRIAM LUSICA-TAMAYO, M.S.C.E., F.ASEP ASEP Immediate Past President

* The present National Building Code exempts some houses from Earthquake analysis.

REALITY CHECK

WHY

* NSCP Vol. 1 is deemed very stringent for houses and therefore, not followed/observed. houses fall down

* There is no strict implementation of product standards for housing construction. * “I am building JUST A HOUSE, not a building.”

REALITY CHECK OBJECTIVE of NSCP 3: To come up with a housing code which will ensure the safety of people and property against hazards.

* Overloading * “Experienced” workers with the WRONG experience. And so on …

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NSCP 3 REALITY CHECK * Overloading * “Experienced” workers with the WRONG experience. And so on …

4. Simplified presentation of minimum loads 5. Minimum sizes and reinforcements for “typical cases”, especially for masonry 6. Appendix: Detailing for Earthquake-resistant structures Detailing for Typhoon-resilient structures Site Selection

Typical Concerns that prompt professional service

NSCP 3 will

NSCP 3 1. Applicable to one- to two-family dwellings. 2. Prescriptive limits for column-spacing and floor-tofloor heights. 3. Shall cover: Reinforced concrete construction Wood construction Light gage construction Composite construction Alternative materials

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Focus on critical construction details related to building envelope, such as correct spacing of roof sheathing nails, adequate use of roof tiedowns, window protection.

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Emphasize construction quality.

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NSCP 3 will 3. Simplify wind and seismic design requirements to a degree commensurate with knowledge and uncertainty as to how homes actually perform. 4. Emphasize design precautions against locating homes in steep slopes and weak soils.

HISTORY OF BUILDING CODES

Why

building codes and regulations change over the years

Historically building codes are very reactive in that when a problem occurs the building codes change to ensure that the problem never happens again.

EARLY “BUILDING CODES” PURPOSE OF BUILDING CODES

For the protection of public health, safety and general welfare.

First Building Code: Code of Hammurabi 229.

230. 231. 232.

233.

If a builder builds a house for someone, and does not construct it properly, and the house which he built falls in and kills its owner, then that builder shall be put to death. If it kills the son of the owner, the son of that builder shall be put to death. If it kills a slave of the owner, then he shall pay, slave for slave, to the owner of the house. If it ruins goods, he shall make compensation for all that has been ruined, and inasmuch as he did not construct properly this house which he built and it fell, he shall re-erect the house from his own means. …….

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EARLY “BUILDING CODES”

Why? Because of …

Biblical Reference: Law of Moses Deuteronomy, Chapter 22 verse 8 "In case you build a new house, you must also make a parapet for your roof, that you may not place bloodguilt upon your house because someone falling might fall from it."

Why? Because of …

1 Wake-up calls

Why? Because of …

Why? Because of …

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NEW

Research Products Technology

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Why? Because of …

Why? Because of …

New Laws. Amendments to existing laws.

So, how do we divide the pie? Why? Because of …

Our LAW says we can SHARE! Our LAW says the PIE is ours!

You’re all WRONG! The PIE is ours! Our LAW says the PIE is ours!

Why? Because of …

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Why? Because of …

4 Initiatives of Professional Groups

Government initiatives

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Why? Because of …

Why? Because of …

Department Orders. Ordinances. Memorandum Circulars.

Typo errors, Wrong crossreferencing. Missing parts, etc.

Hearsay: DPWH says “Henceforth, Design Wind force will be based on 300 kph”

We have established the WHYs behind the revisions of the building codes and regulations… Victims of Typhoon Pablo (Dec 2012)

Initiatives of Professional Groups

Why? Because of …

5 Benefits of a closer look

NEW Research, Products, Technology

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Government

4 Initiatives

5 Benefits of a Closer Look

WAKE-UP CALLS

1 reasons

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For the Codes to be effective, we need: By REVISING and UPDATING the CODES, is the SAFETY OBJECTIVE met? Is it Guaranteed?

COMPLIANCE by the public.

For the Codes to be effective, we need: By REVISING and UPDATING the CODES, is the SAFETY OBJECTIVE met? Is it Guaranteed?

ENFORCEMENT by the government.

Not always.

To be safe… What is needed?

Compliance by the public.

Enforcement by the government

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“The best thing you can do is the right thing; the next best thing you can do is the wrong thing; the worst thing you can do is nothing.” -Theodore Roosevelt

Why houses fell down Many of those which failed are non-engineered structures. Failures are due to: 1. Absence/lack of reinforcement. 2. Poor quality of materials. Use of sea sand in concrete mixes. Sub-standard CHB. 3. Free-standing parapet walls. 4. Small sizes of structural elements 5. Absence of lateral-force resisting system 6. Soft storey (Top heavy) 7. Inadequate anchorage.

“By changing nothing, nothing changes.” -Tony Robbins

To be safe… Remember: “We are in the business of saving lives, not just money.”

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