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Foundation
As a composite of soil, concrete, steel, wood, plastic, and other materials that are designed to work together to provide a stable base that supports a superstructure.
Sebagai komposit tanah, beton, baja, kayu, plastik, dan bahan lain yang dirancang untuk bekerja sama untuk menyediakan dasar yang stabil yang mendukung suatu suprastruktur. ...
MAJDI ALI 2
retak Slab ditemukan di bawah karpet
Tanah adalah Rakasa Tidur
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Alasan untuk Pemeliharaan Pondasi, tergantung pada:
Air bisa membangkitkan monster
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Diklat Fungsional Penilai
Jenis Foundation Suprastruktur Jenis Arsitektur Penutup Jenis Tanah Tanah Air Situs Drainase Situs Vegetasi Iklim Awal Gerakan Tanah
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Plesteran retak di atas jendela Garasi pemisahan haeder
Keep the monster sleeping
Shower ubin / drywall crack Luar memisah pemisahan
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Foundation Inspection Objectives
Metode & Prosedur untuk Mengevaluasi Celah Foundation Residential Struktural, Gerakan, & Kondisi 11
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ni pengalaman luas bidang inspeksi dan pendidikan, dikombinasikan dengan inspeksi bangunan informasi dan hati-hati, memberikan garis pertahanan pertama yang berharga bagi pemilik gedung dan penghuni yang mungkin akan menghadapi kerusakan sebelumnya yayasan tidak dikenal mahal atau berbahaya.
Yayasan inspeksi dilakukan untuk mengidentifikasi & mendokumentasikan kondisi mahal atau berbahaya potensial. pemeriksaan harus mempertimbangkan banyak faktor di luar kondisi jelas terlihat dari yayasan, seperti menghadiri untuk kondisi lokasi, bukti sejarah gerakan bangunan, dan jenis, lokasi, dan tingkat retak dan gerakan. Data ini, dikombinasikan dengan pendidikan dan pengalaman, izin inspektur dasar berpengetahuan untuk memberitahu klien tentang urgensi perbaikan pondasi dan jenis perbaikan yang mungkin diperlukan.
Akuntabilitas: inspektur yang bertanggung jawab untuk bagian terlihat pondasi dan untuk mengenali tandatanda cacat. Dalam beberapa keadaan ini mungkin termasuk kondisi tidak terlihat atau sulit melihat yang ada tetap petunjuk yang memadai: kontekstual, sejarah, atau bukti-bukti sekunder terlihat.
Tindakan: Jika sesuai, inspektur mungkin menyarankan evaluasi lebih lanjut / perbaikan termasuk metode invasif seperti menghapus materi selesai yang meliputi yayasan, di luar penggalian, kerja dengan seorang insinyur yayasan, yayasan perbaikan perusahaan, sebuah perusahaan tes untuk membuat borings tanah, atau lainnya investigasi langkah-langkah....
Bahaya: Karena cacat struktur batu tertentu, seperti melotot di atas dinding batu bata tanah, dapat menyebabkan runtuh terjal dan bencana tiba-tiba, kondisi berbahaya bisa jadi harus hadir di beberapa sifat. Meskipun seringkali ada kondisi tersembunyi yang dapat menyembunyikan kondisi bangunan, kemampuan untuk mengenali kondisi berpotensi mendesak atau berbahaya yang dapat dideteksi adalah penting dalam inspeksi yayasan
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FOUNDATION INSPECTION METHODS Langkah-langkah prosedural umum dan topik utama dalam pemeriksaan yayasan termasuk langkah-langkah ini. Link ke diskusi dari masing-masing topik berada di sisi kiri halaman ini. Faktor situs: situs Amati faktor yang mempengaruhi struktur seperti lereng, drainase, rock, atau kegiatan terdekat seperti peledakan Konstruksi: Mengidentifikasi jenis konstruksi, bahan, urutan konstruksi - sejarah situs, yayasan, dan konstruksi rincian Kejadian Cacat: cacat Amati terjadinya - hal yang telah terjadi pada struktur seperti tanda-tanda gerakan, sejarah, petunjuk lain Kelalaian cacat: cacat Amati peninggalan - hal yang telah ditinggalkan-out atau dihapus (sulit untuk spot) seperti adanya kemungkinan posting pendukung, dermaga, ketahanan, atau komponen penting lainnya Evaluasi Pengamatan: Evaluasi informasi yang telah dikumpulkan (sejarah, pengamatan, petunjuk), bukti visual dampaknya terhadap struktur, dan kepentingan mereka. Mengenali kapan ahli evaluasi tambahan atau perbaikan yang dibutuhkan oleh sebuah yayasan atau insinyur struktur atau spesialis dasar perbaikan Laporan Pengamatan & Membuat Rekomendasi: yang Berkomunikasi pengamatan dan rekomendasi kepada klien dengan jelas sehingga klien memahami implikasi dari temuan 13 dan perlunya tindakan (jika ada).
1. SITE FACTORS AFFECTING FOUNDATIONS - in Foundation Damage Diagnosis: How to Observe Site Factors Which May Damage a Building Foundation • Area History in Foundation Damage Diagnosis: Is there evidence of a history of earthquakes, landslides, mud slides, soil settlement, sink holes, construction on fill, or buried debris on or at sites in the area? • Area geology in Foundation Damage Diagnosis • Soils in Foundation Damage Diagnosis: Are there problem soils such as wet, expansive clay soils, scree, bedrock, boulders, buried debris, evidence of fill? Problems having soil characteristics as their origin can show up years later. • Original and Surrounding Slopes: show the original direction of excavation-sequence used in constructing a building. • tepped foundation footings: are a normal practice on steep slopes • Exposure of foundation to mechanical or vehicle damage: A driveway close to the foundation wall, common in older cities, e.g. NYC & Toronto, exposes foundations to damage when heavy trucks such as an oil tank truck or a cement delivery truck pass close to the building to make a delivery • Water, Foundation Leaks, Wet Basements in Foundation Damage Diagnosis: Trees (their roots) and rocks which are near the foundation define areas to watch out for both root damage to a foundation and, more subtle, water entry from ground water (or roof spillage) which is directed towards the building foundation wall • Nearby Roadways: may expose a building foundation (or other components) to damage from traffic-induced vibration.
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2. YAYASAN KONSTRUKSI-Mengidentifikasi Yayasan Tipe Konstruksi, Bahan, Sequence
3. DEFECTS OF OCCURRENCE - Identify Foundation Defects of Occurrence
Sequence Konstruksi Pertimbangan Yayasan Persiapan lokasi, pembangunan di isi Penggalian-kesalahan Bentuk dan kesalahan Pijakan Yayasan kesalahan Backfill kesalahan Situs Drainase kesalahan Konstruksi modular keprihatinan Situs peledakan Berdekatan Situs Blasting
3.a. COMMON FOUNDATION FAILURES - Common Foundation Defects of Occurrence – General • Structural / construction defects & damage • Concentrated loads • Excessive backfill height; premature backfill • Improper materials (soft brick, below grade) • Shallow/absent/undermined/cut footings, settlement & frost damage • Improper soil preparation - settling footings & slabs • Foundation damaged during moved/modular building set • Equipment damage (backfill, vehicles) • General Signs of Movement / Damage • Foundation cracks (see "Diagnosis") • Leaning or Tipping • Bulging • Settlement, uniform or differential • Excessive loading, fractures • Interior cracks (trace to source)
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3.b. FAILURES by FOUNDATION TYPE & MATERIAL - Foundation Defects of Occurrence - by Material
Poured Concrete Foundation Defects • Cold Pour Joints in concrete foundations which leave visible lines in the concrete foundation wall are not usually a structural problem but may in some cases form a dry joint which permits water leakage through the foundation wall. Cold pour joints occur when there is too much time delay between subsequent "pours" into the foundation forms. An astute inspector, by noting the position, pattern, and slope of the cold pour joint, can probably determine the position from which the concrete was poured into the forms (the high end of the sloping lines) and the extent of delay between pours (evidence of water leaks through the joints indicates that enough time passed for the lower pour to solidify). • Concrete shrinkage cracks are not usually a structural problem but may permit water leaks through the foundation wall. • Holes and penetrations in concrete foundations such as poorly-sealed openings left for piping for water or electrical lines or where form ties were broken off may form points of water entry into the structure but are not normally a structural concern. • Concrete foundation settlement cracking such as from footing settlement, absence of or poorly prepared footings, water leading to settlement or actual loss of soils, thus undermining the footings (this can occur and can damage most foundation types), or movement of the foundation due to nearby blasting or excavation work.
Diklat Fungsional Penilai
• Concrete foundation damage from horizontal loading, vehicles, frost is less commonly seen than with unit-construction materials such as brick or masonry block but might occur under unusual conditions. • Concrete foundation damage from unusual point loads • Incomplete sealing between foundation sections, leading to later basement leaks and water entry • Poor modular foundation section alignment, poor sealing between sections, particularly at building corners, resulting in foundation leakage • inadequate footing drains (or none), and/or inadequate roof drainage system installation (gutters and leaders) resulting in flooding the foundation and water entry passing under the wall bottom and up over the basement slab at the slab/wall joint. • Excessive spanning of areas with no fill and no footing at all (shown in photo above) • Basement water entry and leak problems require adaptation of common internal trench and drain systems, as cutting the slab to excavate for an internal drainage trench exposes the gravel footings
Wood Foundation Defects
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Stone Foundation Defect List • Bulges: due to frost, water, vehicle loading if vehicles are driven close to walls • Cracks (if mortared): settlement, vehicle driving close to walls • Other: interruptions for mechanicals may destroy the integrity of these walls. In original construction stones were placed in an overlap pattern from course to course. Removing a section of wall may result in future wall movement unless other steps are taken to stabilize the modified section
Brick Foundation Defect List • Bulging brick walls: this is likely to be a bond-brick or bond-course failure - potentially extremely dangerous and very urgent - can presage sudden catastrophic building collapse! • Cracks and Bulges in brick walls (such as the photo above): frost and earth loading can push a below-grade brick foundation wall inwards. • Cracks and loose bricks: frost, settlement, expansion, usually diagonal or stair-stepped, often at building corners where roof spillage is concentrated. • Loose bricks and missing or lost mortar: and movement where mortar is severely washed-out by roof spillage or other water movement against the foundation. Loose and lost bricks may also occur where wood blocks, originally set into a wall to permit nailing of interior components, is damaged by insects or decay. • Spalling bricks: spalling is caused by water and frost, such as water leaking into a brick structure at (improperly) caulked and rusty steel lintels, improper brick masonry structure or wall "repair work" or re-pointing using hard mortar on soft brick where originally a soft highlime mortar was used.
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Masonry block (concrete & "cinder block") Foundation Defect List ▫ Leaning: water, frost, vehicles, footings ▫ Buckled: water, frost, vehicles - potentially urgent depending on circumstances and amount ▫ Cracks: water, frost, vehicles, shrinkage/expansion, footings ▫ Poured concrete ▫ Leaning: water, frost, vehicles, footings ▫ Cracks*: settlement, shrinkage, cold joints ▫ Spalling: poor mix, cold weather construction, erosion ▫ Shrinkage: improper mis-diagnosis. Concrete blocks don't shrink. Check the other possibilities. ... ▫ Wood foundations (not considered here) ▫ Pile foundations (not considered here) ▫ Tipping/undermining - serious defects ▫ Identify (Possible) Missing Components ▫ missing footings, piers, reinforcement, drainage
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FOUNDATION CRACK EVALUATION - How to Inspect & Evaluate Building Foundation Cracks & Movement & Foundation Crack Patterns
4. FOUNDATION DEFECTS OF OMISSION - Identify Foundation Defects of Omission
General Suggestions for the Evaluation of Foundation Cracks
• Missing supporting column such as a basement Lally column, where an owner has removed the column to open up a basement space being remodeled for use as living area • Missing footings (may or may not be a defect depending on design and soil conditions) • Omitted steel reinforcement - footings (not visibly detectable after construction) • Omitted steel reinforcement - walls (not visibly detectable after construction) • Missing piers beneath interior posts • Missing control joints in poured concrete • Missing expansion joints in large brick masonry walls • Missing expansion joints/materials around windows in brick masonry walls
• Look at shape, pattern, frequency of occurrence, relationship to wall discontinuities and angles, placement of wall penetrations, correlation with cracks in floors, and location in the wall (corners, center), as well as length, width, continuity, age of wall, relation to site conditions (depth of backfill, blasting, rock). • Shrinkage cracks are usually uniform in width or (less common) vee-shaped, wider at top and diminishing or stopping before reaching the bottom of the foundation wall (where attachment to footing may tend to hold foundation wall materials in place). A wall crack which continues into the floor is likely to involve the building footings and may be a settlement crack of more structural importance. • Concrete shrinks as it cures. In poured concrete, shrinkage cracks may be non-uniform if wall components are held by footings/framing; very often there are minor shrinkage cracks which are hairline, random, intermittent, multiple, and meandering in the concrete, forming discontinuous cracks in the wall. Shrinkage cracks occur as concrete cures, appearing more frequently and larger if the mix was improper and where control joints were omitted. Omission or pattern of placement of steel reinforcement may also be a factor in crack formation and location. • Poured concrete shrinkage cracks: usually shrinkage cracking is due to conditions at original construction: poor mix, rapid curing, possibly other conditions. Shrinkage cracks are less likely to require structural monitoring and repair in poured concrete as they would be expected to continue after initial curing.
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General Suggestions for the Evaluation of Foundation Cracks • Concrete block foundation walls shrink as they cure. They rarely expand much on exposure to moisture and temperature variations. In concrete block walls shrinkage cracks are likely to be uniform in width and usually occur towards the center of a concrete masonry unit (CMU) wall. The wall is stronger at the building corners. • Brick walls do not normally shrink, but rather, grow indefinitely. Bricks are not often used for below-grade foundations but were often used above-grade supporting the first floor of older buildings, and of course entire buildings may be constructed using structural brick walls (look for the bond courses). If you see a crack in a brick wall it's more likely due to movement in the structure, a support problem, or due to thermal expansion. Cracks in structural brick walls may be very serious if the bond courses are broken as there is then a risk of sudden catastrophic wall collapse. Cracks and especially bulged cracked brick walls need immediate expert investigation. • Stone foundation walls do not normally crack through individual stones, but the interlaced stone layout of the wall may be bulged and cracked due to damage from frost, loading from driving vehicles near the wall, or by the removal of stones to pass piping or make doorways. As with other cases of foundation movement, a diagnosis of the cause, amount of movement, and effects on structure are needed to decide what repair may be needed
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5. FOUNDATION DAMAGE REPORTS - How to Report Foundation Damage
Making Foundation Monitoring/Action Recommendations Possible outcomes and report information include: • Do Nothing (cosmetic, minor) • Monitor for signs of movement • Evaluate Further • Repair, replace, improve, provide* • Priority: urgent or defer* • Cost estimates: major/minor* • References to authoritative sources* • References to foundation repair experts*
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FOUNDATION REPAIR METHODS
FOUNDATION REPAIR METHODS
Repair Methods for Foundation Shrinkage Cracks
Water entry leaks at foundation cracks: Polyurethane foam sealant is used for foundation crack repairs to stop water entry. (Also find and correct outside water sources). Structural repairs as well as sealing against water entry may be attempted for cracked foundations using masonry epoxy products. These products may be used for repairing cracks in concrete foundations following evaluation and advice from a foundation professional. An evaluation of the presence, absence, or condition of reinforcing steel in cracked concrete foundations should be a part of such an inspection.
Repair Methods for Vertical Foundation Movement - Foundations, slabs, fireplaces, chimneys
Grout pumping - suitable if bearing rock is not too deep;
Driven steel pins - $1000./pin for average. 30 ft. depth. (more precise leveling control across the building, possible durability problem? Warranted 60 years)
Chance screw piers - reconstruction
Friction piers, driven piles (Failing at Vancouver Is.)
Excavation and reconstruction, possibly with reinforcement over original design and with additional foundation and site drainage
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FOUNDATION REPAIR METHODS
Repair Methods for Bulged Foundation Walls
horizontal driven pins, steel tension cables + stars
pilasters
steel beams anchored to slab and framing
reconstruction
inside reinforcing wall
SELESAI
Excavation and reconstruction, possibly with reinforcement over original design and with additional foundation and site drainage
Horizontal foundation movement creep
Pin to hills, etc. is a separate engineering problem. Excavation and reconstruction, possibly with reinforcement over original design and with additional foundation and site drainage 27
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