One of the most epic engineering feats in history - Alex Gendler

Translator: Aditya Bachtiar Reviewer: Reno Kanti Riananda

In the mid-19th century,

Pada pertengahan abad ke-19,

suspension bridges were collapsing all across Europe.

jembatan gantung berjatuhan di seluruh Eropa.

Their industrial cables frayed during turbulent weather

Kabel-kabel rusak termakan terpaan cuaca,

and snapped under the weight of their decks.

dan runtuh karena tak kuasa menahan beban.

So when a German-American engineer named John Roebling

Saat insinyur Jerman-Amerika bernama John Roebling

proposed building the largest and most expensive suspension bridge

mengusulkan pembangunan jembatan terbesar dan termahal

ever conceived over New York’s East River,

yang pernah dibangun di atas New York East River,

city officials were understandably skeptical.

wajar bila pemerintah merasa ragu.

But Manhattan was increasingly overcrowded,

Namun, Manhattan semakin padat,

and commuters from Brooklyn clogged the river.

dan komuter dari Brooklyn memadati sungai tersebut.

In February of 1867, the government approved Roebling’s proposal.

Pada bulan Februari 1867, pemerintah menyetujui ide Roebling.

To avoid the failures of European bridges,

Untuk menghindari kegagalan serupa dengan jembatan di Eropa,

Roebling designed a hybrid bridge model.

Roebling merancang sebuah jembatan hibrida.

From suspension bridges,

Dari model jembatan gantung,

he incorporated large cables supported by central pillars and anchored at each bank.

ia memasang kabel besar di pilar utama dan diikat di tiap sisi sungai.

This design was ideal for supporting long decks,

Desain ini cocok untuk menopang jembatan panjang,

which hung from smaller vertical cables.

yang menggantung pada kabel vertikal yang lebih kecil.

But Roebling’s model also drew from cable-stayed bridges.

Namun, model ini juga didasari oleh jembatan kabel.

These shorter structures held up their decks with diagonal cables

Struktur yang lebih pendek ini menahan lantai jembatan menggunakan kabel diagonal

that ran directly to support towers.

yang tersambung langsung ke tiang penopang.

By adding these additional cables, Roebling improved the bridge’s stability,

Kabel tambahan ala jembatan Roebling ini menambah kestabilan jembatan,

while also reducing the weight on its anchor cables.

sekaligus mengurangi beban kabel-kabel penopang.

Similar designs had been used for some other bridges

Desain serupa telah digunakan di beberapa jembatan lain,

but the scope of Roebling’s plan here dwarfed them all.

tetapi desain Roebling lebih unggul.

His new bridge’s deck spanned over 480 meters—

Jembatan baru ini memiliki panjang 480 meter—

1.5 times longer than any previously built suspension bridge.

1,5 kali lebih panjang dari jembatan gantung mana pun.

Since standard hemp rope would tear under the deck’s 14,680 tons,

Karena tali biasa akan putus pada beban 14,680 ton,

his proposal called for over 5,600 kilometers of metal wire

Roebling menggunakan kabel besi sepanjang 5. 600 kilometer

to create the bridge’s cables.

sebagai kabel penopang jembatan.

To support all this weight,

Dengan beban seberat ini,

the towers would need to stand over 90 meters above sea level—

tiang jembatan harus dibangun setinggi 90 meter di atas permukaan laut--

making them the tallest structures in the Western Hemisphere.

menjadikannya bangunan tertinggi di Barat.

Roebling was confident his design would work,

Roebling percaya rancangannya akan sukses,

but while surveying the site in 1869,

tetapi saat meninjau lokasi di tahun 1869,

an incoming boat crushed his foot against the dock.

sebuah kapal menghempas kakinya ke dermaga.

Within a month, tetanus had claimed his life.

Sebulan kemudian, tetanus merenggut nyawanya.

Fortunately, John Roebling's son, Washington, was also a trained engineer

Untunglah putranya, Washington, juga seorang insinyur,

and took over his father’s role.

dan meneruskan peran ayahnya.

The following year, construction on the tower foundations finally began.

Setahun kemudian, pembangunan tiang pondasi akhirnya dimulai.

This first step in construction was also the most challenging.

Tahap pertama konstruksi juga merupakan tantangan yang sangat besar.

Building on the rocky river bed involved the use of a largely untested technology:

Membangun di dasaran sungai berkerikil dengan teknik yang belum pernah dipakai:

pneumatic caissons.

caisson pneumatik.

Workers lowered these airtight wooden boxes into the river,

Pekerja menurunkan kotak kayu kedap udara ke sungai,

where a system of pipes pumped pressurized air in and water out.

di mana sistem pipa akan memompa udara masuk dan membuang air keluar.

Once established, air locks allowed workers to enter the chamber

Setelah terpasang, pekerja bisa masuk ke ruangan tersebut

and excavate the river bottom.

dan menggali dasar sungai.

They placed layers of stone on top of the caisson as they dug.

Mereka menyusun lapisan batu sembari menggali.

When it finally hit the bedrock, they filled it with concrete,

Saat mencapai dasar sungai, adonan semen dimasukkan,

becoming the tower’s permanent foundation.

yang akan menjadi fondasi permanen jembatan.

Working conditions in these caissons were dismal and dangerous.

Bekerja dalam ruangan ini sangat berbahaya.

Lit only by candles and gas lamps, the chambers caught fire several times,

Penerangan dengan lilin dan lampu gas seringkali menyebabkan kebakaran,

forcing them to be evacuated and flooded.

sehingga ruangan harus dievakuasi agar dapat diisi air.

Even more dangerous was a mysterious ailment called "the bends."

Yang lebih berbahaya adalah penyakit misterius "nyeri sendi".

Today, we understand this as decompression sickness,

Saat ini, kita mengenalnya sebagai penyakit dekompresi.

but at the time, it appeared to be an unexplainable pain or dizziness

Namun dahulu, ini adalah rasa nyeri dan sakit kepala yang tak dapat dijelaskan

that killed several workmen.

yang membunuh beberapa pekerja.

In 1872, it nearly claimed the life of the chief engineer.

Pada 1872, kepala insinyur hampir menjadi korban.

Washington survived, but was left paralyzed and bedridden.

Washington selamat, meskipun ia jatuh lumpuh.

Yet once again, the Roeblings proved indomitable.

Namun sekali lagi, keluarga Roebling terbukti gigih.

Washington’s wife Emily not only carried communications

Istri Washington, Emily, tak hanya membantu komunikasi

between her husband and the engineers,

antara suaminya dengan para pekerja,

but soon took over day-to-day project management.

tetapi juga mengambil alih peran pengelola proyek.

Unfortunately, the bridge’s troubles were far from over.

Sayangnya, masalah lain muncul kembali.

By 1877, construction was over budget and behind schedule.

Pada tahun 1877, konstruksi melebihi anggaran dan terlambat dari jadwal.

Worse still, it turned out the bridge’s cable contractor

Kabar buruk lainnya, ternyata kontraktor kabel jembatan

had been selling them faulty wires.

memberi mereka kabel yang cacat.

This would have been a fatal flaw if not for the abundant failsafes

Ini akan menjadi kesalahan yang fatal jika tak ada berbagai pengaman cadangan

in John Roebling’s design.

pada jembatan rancangan Roeblings.

After reinforcing the cables with additional wires,

Setelah dipasang kabel penguat tambahan,

they suspended the deck piece by piece.

lantai jembatan diletakkan satu per satu.

It took 14 years, the modern equivalent of over 400 million dollars,

Dibutuhkan 14 tahun, lebih dari 400 juta dolar,

and the life’s work of three different Roeblings,

dan pekerjaan seumur hidup tiga anggota keluarga Roeblings.

but when the Brooklyn Bridge finally opened on May 24, 1883,

Namun, saat Jembatan Brooklyn diresmikan pada tanggal 24 Mei 1883,

its splendor was undeniable.

kemegahannya tak terbantahkan.

Today, the Brooklyn Bridge still stands atop its antique caissons,

Hari ini, Jembatan Brooklyn masih berdiri di atas caisson antiknya,

supporting the gothic towers and intersecting cables

menopang tiang bergaya gotik dan persilangan kabel-kabel

that frame a gateway to New York City.

yang menghias gerbang menuju Kota New York.