探索下一代重型木結(jié)構(gòu)科研建筑

查德·吉信

科研建筑市場的快速增長、科研建筑開發(fā)商的激烈競爭正在推動實驗室空間和科研場所的需求升級，他們不斷改進現(xiàn)有的科研空間，為租戶創(chuàng)造與眾不同的辦公場所。在美國多地的商業(yè)地產(chǎn)市場中，對實驗室和科研辦公空間的需求一直十分旺盛，加劇了科研建筑開發(fā)商之間的競爭。2022 年第三季度，在美國最大的12 個商業(yè)地產(chǎn)市場中，開發(fā)中（包括新建和改造）的生命科學地產(chǎn)的建筑面積創(chuàng)紀錄地達到了約3470,000m2（3740 萬ft2）[1]。

與此同時，對可持續(xù)發(fā)展興趣的升溫讓許多開發(fā)商開始尋找混凝土和鋼結(jié)構(gòu)的替代品，因為這兩種材料的碳排放量都非常高。隨著綠色建筑領(lǐng)域知識的普及和建筑規(guī)范的調(diào)整，建筑行業(yè)及相關(guān)客戶逐漸將重型木結(jié)構(gòu)視為未來的發(fā)展浪潮。美國木制品委員會在2019 年的一份報告中提到，美國已建成和規(guī)劃中的木結(jié)構(gòu)商業(yè)建筑接近600座，到2022 年9月，這個數(shù)字幾乎翻了2倍，全美有1571 個采用重型木結(jié)構(gòu)的項目處于施工或設(shè)計階段[2]。顯然，可持續(xù)建造和新的施工方式正在興起和流行，甚至聯(lián)邦政府也加入了這一浪潮：拜登政府宣布撥款3200 萬美元支持木材行業(yè)的創(chuàng)新，其中就包括重型木結(jié)構(gòu)[3]。

在科研建筑競爭加劇、重型木結(jié)構(gòu)日漸流行的兩個趨勢疊加之下，我們的研究團隊認識到了行業(yè)面臨的挑戰(zhàn)也看到了創(chuàng)新的機遇。如何優(yōu)化實驗室設(shè)計為租戶創(chuàng)造獨特的體驗，增強產(chǎn)品的差異性，并提供一種以可持續(xù)、韌性和去碳化為核心的設(shè)計方案？我們認為答案是從內(nèi)到外去設(shè)計一座建筑，而不是從外到內(nèi)。我們與結(jié)構(gòu)設(shè)計單位KPFF、機電設(shè)計單位Buro Happold合作，開展了一項由Gensler 研究所資助的、衡量實驗室建筑影響的研究項目，對下一代科研建筑進行概念設(shè)計，探索科研建筑的性能、外觀和人體感受。我們把這個項目稱為“下一代”（NEXT）實驗樓。

1-3 結(jié)構(gòu)體系比較在建筑體驗方面，重型木結(jié)構(gòu)容易營造出溫暖的感覺，而不同于混凝土或鋼結(jié)構(gòu)，需要用額外的室內(nèi)裝飾隱藏材料的冰冷感Comparison of structural systemsFrom an experiential point of view,mass timber produces a visually warm environment without having to add additional finishes to counter the cold feeling of concrete or steel

設(shè)計與研究團隊

Gensler團隊：Chad Yoshinobu,Hau Vong,Nathan Butt,Lucianna Scordo,Glen Berry,Justin Cratty,Erik Lustgarten,Anthony Brower

Buro Happold團隊：John Swift,Richard Waldner,Justin Mole,Kristen Brozowski

KPFF團隊：Brian Pavlovec,Jacob McCann,Shana Kelley

Research &Design Team

Gensler:Chad Yoshinobu,Hau Vong,Nathan Butt,Lucianna Scordo,Glen Berry,Justin Cratty,Erik Lustgarten,Anthony Brower

Buro Happold:John Swift,Richard Waldner,Justin Mole,Kristen Brozowski

KPFF:Brian Pavlovec,Jacob McCann,Shana Kelley

In a fast-growing market,the increased competition among science building developers is driving the demand for lab space and science workplaces,challenging the status quo to create differentiation for tenants.The demand for lab space and science workplaces remains strong in many markets,increasing competition among science building developers.Across 12 of the largest markets in the U.S.,a record 37.4 million square feet of life sciences space– both new construction and conversions– was under development in the third quarter of 2022[1].

At the same time,a surge of interest in sustainable development has many developers looking at alternatives to concrete and steel construction,both of which have a significantly high carbon output.As experience in the field grows quickly and building codes adapt,the construction industry and their clients are quickly looking to mass timber as the wave of the future.The Wood Products Council reported in 2019 that there were nearly 600 commercial timber buildings planned or built in the U.S.By September 2022,that number had nearly tripled,with 1571 mass timber projects either constructed or in the design phase[2].It is clear that sustainable construction and alternative construction methods are on the rise and will continue to grow in popularity.Even federal governments are joining the call,as evidenced by a $32 million appropriation announced by the Biden Administration to support innovations in the wood industry,including mass timber[3].

At the intersection of these two trends,our research team recognised the challenges facing the industry and saw an innovation opportunity.How could we optimise lab design,create a unique tenant experience,increase product differentiation in the marketplace,and offer a design solution that prioritises sustainability,resilience,and decarbonisation? The answer was to design the building from the inside-out,rather than the outside-in.In partnership with structural engineers KPFF and MEP engineers Buro Happold,we embarked on an ongoing measurable impact research project funded by the Gensler Research Institute to develop a conceptual framework for the next evolution of science buildings– both in terms of how they will perform,and what they will look and feel like.We call it the NEXT lab.

1 Choosing Mass Timber

NEXT prioritises both construction efficiency and waste reduction,delivering a resilient building in a shorter speed-to-market time.Mass timber is particularly well suited to off-site construction,in which building components can be produced in a factory and delivered to the site as a kit of parts.These components can be assembled up to 30% faster than a conventional concrete lab building,and that accelerated schedule yields 10% in cost savings over a typical concrete building.In addition,mass timber buildings are lighter than concrete or steel buildings,so their foundations don't have to be as extensive or expensive[4].

With up to 85% fewer deliveries to the site and up to a 75% reduction in construction waste,our calculations show that if we make the building out of sustainably sourced wood– a renewable resource– NEXT reduces the embodied carbon of the building by up to 80% compared to a conventional concrete lab building.That amounts to a saving of approximately 6,800 total metric tonnes of CO2,which is the equivalent of removing 1460 cars from city roads for an entire year.

Aesthetically,mass timber-framed buildings provide other benefits.They are naturally warm in comparison to concrete and steel structures,lending a pre-built finish to the interior.A concrete building would require additional design elements,typically specialty materials,to warm the aesthetics of the space.Applying those additional elements would add material and labour costs and more time to the schedule.

2 Selecting the Site

To conceptualise a building that would respond to real world conditions and provide a basis for our energy modelling and analysis,we needed to work with a specific site.We began by researching possible locations in the U.S.that could support the implementation of the project.For guidance,we looked at mass timber resource availability and manufacturer proximity,local codes and standards,the existing network of life science hubs and mass timber project precedents.

4.5 項目場地研究團隊將場地選在了西雅圖的上城區(qū)，這里非常適宜步行，也是生命科學產(chǎn)業(yè)聚集地和本地的文化藝術(shù)中心Building siteThe team selected a site in Seattle's walkable Uptown District,a hub for life sciences and a local center for arts and culture.

6.7 向西南方向看項目 View looking southwest

8 東立面木桁架解決了水平方向的結(jié)構(gòu)要求，也為租戶增添了視覺趣味 East fa?adeCross-bracing addresses the requirements for structural lateral bracing as well as adding visual interest for tenants

1 選擇重型木結(jié)構(gòu)

“下一代”實驗樓的首要任務(wù)是提升施工效率和減少浪費，在更短的時間內(nèi)建成具有韌性的建筑。重型木結(jié)構(gòu)特別適合場外施工，即在工廠生產(chǎn)建筑構(gòu)件后打包運送到施工現(xiàn)場。組裝這些構(gòu)件相比傳統(tǒng)現(xiàn)澆混凝土能夠提速30%，從而縮短工期節(jié)省10%的成本。此外，采用重型木結(jié)構(gòu)的建筑比混凝土或鋼結(jié)構(gòu)建筑更輕，因此所需地基也更淺、更經(jīng)濟[4]。

我們的計算表明，如果使用可持續(xù)來源的木材（屬于可再生資源）來建造，則運輸?shù)浆F(xiàn)場的建材可以減少85%，建筑垃圾可以減少75%?！跋乱淮睂嶒灅怯捎诓捎弥匦湍窘Y(jié)構(gòu)，隱含碳排放比傳統(tǒng)混凝土建筑減少了80%，相當于一座大樓可以減少約6800t 的CO2排放，這相當于1460 輛汽車在城市道路上一整年的排放量。

重型木結(jié)構(gòu)建筑在美學方面也具有優(yōu)勢。與混凝土和鋼結(jié)構(gòu)相比，重型木結(jié)構(gòu)天然地給人溫暖的感覺，并且為室內(nèi)裝修提供了預(yù)制的木飾面?；炷两ㄖ枰~外的室內(nèi)裝飾，通常是采用一些特制的材料才能營造出空間的美感。這些額外的裝修會增加材料和人工成本并延長施工時間。

2 選擇場地

為了設(shè)計出一座能夠應(yīng)對現(xiàn)實條件的重型木結(jié)構(gòu)建筑并用于能源建模與分析，需要選擇一個具體的場地。我們首先研究了美國范圍內(nèi)可行的地點，研究要素包括場地的重型木結(jié)構(gòu)資源可得性、場地與制造商的距離、當?shù)胤ㄒ?guī)和建筑規(guī)范，我們也研究了現(xiàn)有的生命科學產(chǎn)業(yè)網(wǎng)絡(luò)以及大量重型木結(jié)構(gòu)項目的案例。

我們通過調(diào)查制造商的分布來確定在美國哪些地區(qū)最容易獲得重型木結(jié)構(gòu)產(chǎn)品。易于理解的是，制造商通?？拷试S采伐的森林。每個地區(qū)可用的樹種也不同——從美國西北地區(qū)的北美黃杉到東南部的美國南方松。令人欣喜的是，我們發(fā)現(xiàn)全美范圍內(nèi)重型木結(jié)構(gòu)制造商的數(shù)量在不斷增長。

對于這項研究，我們最終選擇了華盛頓州西雅圖市的一個城市地段作為場地。此前，我們的科學小組探索了許多不同城市的地點和街區(qū)，最終選擇的場地具有豐富的可能性，它位于西雅圖市中心（標志性的太空針塔所在處）和聯(lián)合湖南區(qū)（亞馬遜總部所在地）之間。

這兩個地標之間的上城區(qū)是西雅圖非常適合步行的街區(qū)。這個新興街區(qū)不僅有空地可開發(fā)，而且已經(jīng)有流行文化博物館和比爾及梅琳達·蓋茨基金會等重要景點，還有太平洋科學中心、奇胡利花園和玻璃藝術(shù)館，以及太平洋西北芭蕾舞團的所在地馬里恩奧利弗麥考劇院。此外，生命科學產(chǎn)業(yè)在該地區(qū)的發(fā)展中占據(jù)重要地位，這也是我們把項目場地選在這里的一個重要原因。

3 基本設(shè)計原則

除了考慮材料、運營成本、環(huán)境健康和市場需求等因素外，我們還希望將面向未來的生命科學建筑視為一個新的設(shè)計問題去解決。我們首先重新審視了大多數(shù)傳統(tǒng)科研建筑采用的長方形盒子結(jié)構(gòu)，這種建筑大多數(shù)使用中央核心筒布局，位于樓層中央的電梯間將租戶空間分隔開，限制了租戶的視覺和物理聯(lián)系。在我們的項目中，將核心筒從建筑的中心移到邊緣，這解決了西面的視野被相鄰建筑阻擋的問題。核心筒移動后還釋放了租戶空間的進深，使租戶可以最大限度地靈活規(guī)劃室內(nèi)布局。

此后，我們批判性地審視了核心筒本身。我們認為核心筒內(nèi)的消防樓梯是建筑物中最未充分利用的資產(chǎn)。我們開始考慮如何讓樓梯成為租戶可以使用的一項設(shè)施，而不僅僅是為了滿足消防規(guī)范。于是，我們將核心筒改到臨街道的一側(cè)，緊靠玻璃幕墻立面，從而使樓梯間能享受到陽光和景觀。這個做法為整個建筑創(chuàng)造了一項新資產(chǎn)——樓梯成為一種有利健康的設(shè)施，為員工們提供了一個比乘坐電梯更健康的交通方式。如果租戶租用了兩層以上的樓層，他們就不再需要自己修建樓梯，而是可以刷電子門禁卡來使用消防樓梯。這大大地降低了成本和裝修時間。

9 主要設(shè)計概念項目的設(shè)計概念由幾個主要步驟生成：首先，我們決定將核心筒放置在建筑邊緣，以盡可能增大租賃空間的進深；其次，將核心筒放在靠街道的外側(cè)，以創(chuàng)造一個可以看到街景的樓梯間；我們選用了約10m×10m（33ft×33ft）的柱網(wǎng)，可以為實驗室的布局提供更大的靈活性；接下來，我們確保每層樓和屋頂都有室外活動空間，首層則有一系列公共功能可以成為社區(qū)的催化劑Key design conceptsConceptually,the design is based on a handful of strategic steps.First,the core was shifted to the perimeter to maximize the interior lease depth.Then the core was placed along the street edge to create an interconnecting stair with views to the adjacent pedestrian street.The structure was designed with a 33 ft×33 ft grid that allows greater flexibility for lab layouts.Each floor and the rooftop enjoy access to outdoor space.And the ground floor was programmed to serve as a community catalyst

10 東立面玻璃幕墻立面的一部分是可以調(diào)節(jié)的，從而使建筑在1/3的工作時間內(nèi)都可以進行自然通風East fa?ade Operable panels in the fa?ade allow for the building to be naturally ventilated one-third of the work hours

11 東立面East fa?ade

12 北立面開放互通的樓梯間（圖中右側(cè)）有助于健康、協(xié)作工作氛圍的形成North fa?adeThe interconnecting stair (at right in image) encourages a healthy workplace and promotes collaboration

Our examination of manufacturers,for example,helped us identify the regions in the country where mass timber products are most readily available.Understandably,manufacturers are usually near the forests from which the timber is harvested.Each region has different availability of tree species,as well– from Douglas fir in the northwest region to Southern yellow pine in the southeast.We also found the number of manufacturers is growing around the country,which is encouraging.

For this specific research project,we selected an urban site in Seattle,Washington.Our science group explored alternative locations in many different cities– and many different districts within those cities– before we selected Seattle.The site we ultimately selected is rich with possibilities,located between the Seattle Center,which is easily recognised by the iconic Space Needle,and the larger South Lake Union district,the location of Amazon's headquarters.

Between those two landmarks is Seattle's walkable Uptown District.This emerging neighbourhood not only has developable lots,but is already populated with important sites such as the Museum of Pop Culture and the Bill and Melinda Gates Foundation.It also boasts the Pacific Science Center,the Chihuly Garden and Glass Museum,and Marion Oliver McCaw Hall,home to the Pacific Northwest Ballet.In addition,the life sciences industry is a big player in the growth of this district,a factor that heavily influenced our decision to pick this specific site for our project.

3 Basic Design Tenets

In addition to considering factors such as materiality,operating costs,health and wellness,and market demands,we wanted to treat the future-forward life sciences building as a design problem as well.We started by re-examining the rectangular box that is the standard for most conventional science buildings.The majority of these are centre-core buildings,in which the elevator core bifurcates the tenant space,limiting visual and physical connectivity for tenants.For our project,we decided to relocate the core from the centre to the perimeter of the building,which addressed the fact that views to the west were limited by an adjacent building.Furthermore,moving the core also liberated the lease depth for the tenant spaces,allowing tenants maximum flexibility to plan the interior layout.

Then we looked critically at the core itself.We determined that a fire stair embedded within the core is the most underutilised asset for a building.We began to consider how to make the stairway a tenant amenity,as opposed to being solely a fire code requirement.That prompted us to shift the core to the street front,thereby placing the stair against the exterior glass fa?ade and flooding it with daylight and views.That created a new asset for the entire building– a wellness amenity that provides workers a healthy alternative to elevator transport.And,instead of a tenant having to build their own interconnecting stair if they happen to lease two or more floors,they can use the fire stair for the same purpose using secure card-key access.For a tenant,this significantly reduces costs and schedule impacts.

13 靈活的布局設(shè)計采用約10m×10m（33ft×33ft）的柱網(wǎng)，使租戶可以靈活地安排布局和分隔空間以優(yōu)化工作效率Flexible gridDesigning with a 33 ft×33 ft grid gives tenants flexibility in how they arrange their space and subdivide it to optimize their work

14 裝配式設(shè)計裝配式設(shè)計可將施工速度提高 30%，節(jié)省高達 10% 的總成本。通過工廠預(yù)制部件，需要運到工地的建材可以減少85%Kit of parts designThe kit of parts design can speed construction up to 30%,while generating overall cost savings of up to 10%.The prefabrication process allows for up to 85% fewer deliveries to the building site

4 對實驗室布局的再思考

對于采用重型木結(jié)構(gòu)的建筑，找到理想的柱網(wǎng)尺寸十分重要。我們最終選取了約10m×10m（33ft×33ft）的柱網(wǎng)，這是一個不常見的柱網(wǎng)尺寸，但它是基于實驗室工作臺約3.35m（11ft）的模塊確定的。我們的理由是，這樣的正方形柱網(wǎng)可以為租戶提供更大的靈活性，他們可以自己決定工作臺按南北方向還是東西方向排列。

為了讓這個柱網(wǎng)和重型木結(jié)構(gòu)能夠適應(yīng)實驗室的需要，我們還需要解決地板震動的問題。基于一個人在實驗室空間中行走的腳步，結(jié)構(gòu)工程師將結(jié)構(gòu)系統(tǒng)的震動控制在6000MIPS（μin/s）以內(nèi)。震動峰值出現(xiàn)在樓板的中心，也就是變形最大的地方，越靠近柱子的地方則防震性能逐步提高，震動最終降低到 2000 MIPS 以內(nèi)。

實現(xiàn)這種防震水平的關(guān)鍵是“復(fù)合”：預(yù)制構(gòu)件時將CLT（交叉層壓木材）板與膠合木梁復(fù)合在一起，不僅能加快施工速度、降低成本，還能提高地板的硬度。如果6000MIPS 的防震性能對某些租戶還不夠，我們還可以通過多種方法升級結(jié)構(gòu)系統(tǒng)，包括在實驗室中增加隔墻和加強主次梁的強度。

該項目由于有8 層樓高而被歸類為IV-B 型建筑，耐火時間需要達到2 小時。為達到該標準，木結(jié)構(gòu)必須能夠在發(fā)生火災(zāi)時提供一層炭化保護層。我們設(shè)計的炭化層可以使木材在外部燃燒時內(nèi)部仍然具有所需的結(jié)構(gòu)強度。

5 擁抱室外空間

我們在設(shè)計中還融入了大量的室外空間作為辦公場所的附加設(shè)施。Gensler 美國辦公場所調(diào)查顯示，室外空間在科研工作者最想要的辦公場所設(shè)施中排名第一[5]?；谶@樣的反饋，我們在建筑的每一層都設(shè)計了陽臺和室外平臺，還在屋頂專門設(shè)計了室外空間。每層陽臺都非常寬敞，進深在4.57m（15ft）以上，租戶可以在這里進行會議、研討，也可以在此休息。對于希望吸引新員工和保有老員工的租戶而言，室外空間可以提供附加價值。

6 鏈接社區(qū)

在設(shè)計研究中，我們還探索了科研建筑如何通過激活首層的公共活動而成為社區(qū)的催化劑?！跋乱淮睂嶒灅桥c西雅圖上城聯(lián)盟集團、西雅圖上城文化藝術(shù)聯(lián)合會合作，希望打造一個容納多元化的藝術(shù)與娛樂活動的場所，以支持這個地區(qū)內(nèi)的諸多社區(qū)劇院公司。此外，為了推廣西雅圖多元化的烹飪藝術(shù)，我們?yōu)橛斜ж摰纳贁?shù)族裔創(chuàng)業(yè)者設(shè)置了額外的空間作為餐廳，亦可以作為孵化器。

場地面積：2322.6m2

建筑占地面積：2302.1m2

總建筑面積：18417.1m2，共8 層

主要材料：柱、梁、樓板，主要采用重型木結(jié)構(gòu)，部分采用鋼結(jié)構(gòu)（如東立面使用鋼桁架），地板采用CLT（交叉層壓木材）板和混凝土面層

Site Area:25,000 sf (approx.)

Building Footprint:24,780 sf

Floor Area:198,240 sf on 8 stories

Major materials:Primary structure is mass timber (wood columns,beams,floor structure).Supplemental steel structure,including steel rods at the east fa?ade.Concrete topping on CLT floor structure

7 自然通風

科研建筑的能耗是普通辦公樓的5～10 倍。在能耗如此高的情況下，建筑節(jié)能性能的微小改進也能節(jié)省大量的能源。西雅圖溫和的氣候提供了自然通風的機會，可以通過將辦公空間的部分玻璃幕墻設(shè)置為可調(diào)節(jié)的窗戶來實現(xiàn)。

根據(jù)計算，“下一代”實驗樓的辦公空間一年中有34%的時間可以實現(xiàn)自然通風，這也滿足了客戶對于更多新鮮空氣和室外空間的需求。自然通風設(shè)計加之對建筑圍護結(jié)構(gòu)的一些改善，使這座建筑的運行能耗比傳統(tǒng)實驗室建筑降低了30%。

除此之外，我們觀察到市場上流行的空調(diào)系統(tǒng)正在從天然氣系統(tǒng)轉(zhuǎn)向全電熱泵制冷系統(tǒng)。我們與機電設(shè)計單位Buro Happold 合作為整座建筑設(shè)計了全電系統(tǒng)。典型實驗室建筑的 EUI（能源使用強度）通常在120～140 的范圍內(nèi)，而我們的第一步就是盡可能縮小這個數(shù)字。通過改用全電熱泵制冷系統(tǒng)，我們發(fā)現(xiàn)與傳統(tǒng)實驗室建筑相比，這座建筑可以節(jié)省高達40%的EUI（能源使用強度）。

采用全電熱泵制冷系統(tǒng)后，“下一代”實驗樓產(chǎn)生的溫室氣體排放量將比傳統(tǒng)實驗室建筑少 50%。由于項目同時采用被動式策略和優(yōu)化過的建筑圍護結(jié)構(gòu)與設(shè)備體系，可以節(jié)省相當多的能耗，再加上現(xiàn)場使用可再生能源與場外碳抵消的作用，這座建筑可以實現(xiàn)碳中和目標。

建筑設(shè)備的布置也遵循模塊化的體系。“下一代”實驗樓的頂層空間較為緊湊，是由于我們采用了獨立新風系統(tǒng)，而不是集中式新風系統(tǒng)。對于這樣一座建筑，我們甚至可以考慮使用再循環(huán)通風機，這種技術(shù)已經(jīng)用于某些特定功能的建筑中。我們還優(yōu)化了從非實驗室空間到實驗室空間的能量回收系統(tǒng)。

在某些情況下，平面布局的調(diào)整使實驗室面積減少，我們可以相應(yīng)地減少新風機的配置數(shù)。當然，一些樓層可能不需要配備新風機就可以為租戶騰出更多使用空間。

15 當重型木結(jié)構(gòu)遇到實驗室防震要求項目采用截面約61cm×71cm（24in×28in）的木柱、截面約84cm× 84cm（33in× 33in）的雙主梁和雙T形深約53cm（21in）的次梁，樓板采用覆有約9cm（3.5in）厚混凝土面層的CLT（交叉層壓木材）板，確保實現(xiàn)6000 MIPS（μin/s）的防震性能Mass timber meets lab vibration requirementThe required 6000 MIPS vibration can be accomplished with the mass timber system comprised of 24" ×28" timber columns,33" double girders,and double-T composite action with 21" deep beams,3-play CLT,and a 3.5" concrete topping

4 Rethinking the Lab Layout

Determining the ideal structural grid was an important part of this exercise,given the commitment to using mass timber.We arrived at a 33-by-33-foot grid– an unorthodox dimension for the grid but one that is based on the 11-foot module of a lab bench.We reasoned that a square grid derived from the dimensions of a lab bench provides greater flexibility for tenants,who can determine whether the benches should be arranged in a north-south or east-west direction.

To make this particular grid– and mass timber– work for a lab,we needed to solve for the issue of floor vibration.Our structural engineers tuned the structural system for a 6000 MIPS (micro inches per second) performance,based on the footfall of someone walking through the lab space.The peak vibration occurs in the centre of the bay,where it is most flexible,and the performance improves as one works toward the columns,ultimately exceeding 2000 MIPS.

The key to achieving this level of vibration control was composite action.We prefabricated the CLT (cross-laminated timber) panels with the glulam beams,a strategy that not only speeds up construction and reduces costs but also makes the floor stiffer.And if the 6000 MIPS is not enough for a specific tenant,there are several ways to upgrade the system,including the addition of partition walls in the labs or further strengthening the beams or girders.

Due to the height of the 8-storey building,it is classified as Type IV-B construction,which requires a two-hour fire rating.To meet that standard,the structural timber must be designed to provide a char layer of protection in the event of fire.We designed the char layer so that the timber can burn on the outside and still have the needed structural capacity remaining inside the char layer.

5 Embracing the Outdoors

Our design also incorporates a substantial amount of outdoor space as a workplace amenity.According to the Gensler U.S.Workplace Survey,science workers ranked outdoor space as their #1 most desired workplace amenity[5].To be responsive to that data,we incorporated balconies and terraces on every level of the building and provided additional rooftop outdoor space.The balconies are generous in size– at least 15 feet deep– which allows tenants to have outdoor meetings,conferences,and lounge spaces.It provides added value for tenants hoping to attract and retain staff.

6 Connecting to the Community

In our design studies,we also explored how a science building could be a community catalyst by creating opportunities to activate public programmes at the ground level.In partnership with the Uptown Alliance Group and the Uptown Arts and Cultural Coalition,NEXT was designed to house a multipurpose arts and entertainment venue to support the district's high concentration of community-based theatre companies.To promote the city's diverse culinary arts,additional space is dedicated to restaurant incubator venues for aspiring minority entrepreneurs.

7 Natural Ventilation

Science buildings consume between 5～10 times the energy of a normal office building.Given this high rate of energy use,even incremental improvements in performance can yield substantial savings.Seattle's moderate climate afforded us the opportunity to plan for the use of natural ventilation of the workplace by specifying operable windows for the workplace component of the floor plate.

According to our calculations,the NEXT workplace could be naturally ventilated 34% of the year,which also satisfies clients who want greater access to fresh air and outdoor space.Designing for natural ventilation,in addition to other adjustment to the building envelope,allowed us to reduce the operating energy requirements for this building by 30% over a conventional lab building.

Beyond that,we are seeing a switch in the market from natural gas systems to all electric heat pump chiller systems.We worked with our MEP engineering partner,Buro Happold,to electrify the entire building.On these types of lab buildings,a standard EUI would be in the 120～140 range,and one of our first steps was to reduce that as much as possible.By switching to all-electric systems,we found we could have an EUI savings up to 40% when compared to a conventional lab building.

8 優(yōu)化工作效率

如何通過靈活的平面布局來優(yōu)化工作效率也是我們衡量建筑影響的研究的一部分。建筑與空間可以激活人與人之間的聯(lián)系[6]，鼓勵人們建立信任、相互合作，形成良好的工作文化，激發(fā)更多創(chuàng)意產(chǎn)生。

為了創(chuàng)造一個新的多元化的科研工作場所，促進人們的互動與合作，我們基于鼓勵聚集的原則進行了一系列平面布局的測試。我們希望給科研空間賦予一些新的元素，例如科技辦公場所的協(xié)作性、酒店空間的體驗性和品牌設(shè)計的文化凝聚力。

設(shè)計平面布局的一個關(guān)鍵問題是如何為租戶提供最大的靈活性。我們使用了柱網(wǎng)體系，把核心筒放置在建筑的邊緣，讓租戶能根據(jù)自身的工作文化來最大限度地自由設(shè)計布局。

在第一種平面布局方案中，我們按1:1 的比例設(shè)置實驗室空間與普通辦公空間，這是目前生命科學建筑的常用比例?？紤]到未來的情況，我們還研究了如何在減少實驗室面積的同時提供一個靈活可變的辦公環(huán)境，讓人們可以選擇在不同的地方辦公。此外，我們設(shè)計的室外空間與外部樓梯也可以作為公共使用的協(xié)同空間。

在我們看來，通過盡可能減少實驗室面積來降低碳排放與能耗是生命科學建筑未來的發(fā)展方向。這一目標的實現(xiàn)，離不開計算機建模與機器學習的發(fā)展、實驗設(shè)備尺寸的縮小、生物實驗樣本尺寸的減小和實驗室自動化等一系列因素的支持。我們還設(shè)計了另一種非傳統(tǒng)的平面布局，這一方案考慮了上述因素，同時將一部分需要100%排氣實驗室隔離開，最終實驗室所占面積比例可以低于50%。在這種情形下，其余的非封閉實驗室將成為生物安全第一等級（BSL-1，即防護水平最低等級）的實驗室。

在現(xiàn)實情況下，這種平面布局方案是非常激進的，需要我們與租戶密切合作確定這種布局是否符合他們的需求。然而，考慮到實驗室面積占比不斷縮小是當下的發(fā)展趨勢，租戶都有重要的可持續(xù)發(fā)展目標，而且科學事業(yè)的進步需要協(xié)同合作，我們相信這個非傳統(tǒng)的平面布局是一種面向未來的方案。

9 一種新的可持續(xù)發(fā)展模式

“下一代”實驗樓最終將成為一個激發(fā)租戶和開發(fā)商關(guān)于科研建筑的新想象的平臺。我們呼吁大家共同努力，讓實驗室建筑從傳統(tǒng)走向更具韌性、可持續(xù)發(fā)展性和包容性的未來，一起建立一種空間利用高效的、可持續(xù)的、社區(qū)融合的科研建筑新范式，這也將獲得來自實驗室租戶和開發(fā)商的支持?！?/p>

17 “下一代”實驗樓溫室氣體排放量比傳統(tǒng)實驗樓少50%以我們在西雅圖的研究為例，采用全電熱泵制冷系統(tǒng)替代傳統(tǒng)的天然氣系統(tǒng)，“下一代”實驗樓的溫室氣體排放量將比傳統(tǒng)實驗樓少50%NEXT produces 50% less greenhouse gas emissions than a conventional lab building Using our Seattle case study,by going with all-electric systems as an alternative to natural gas,NEXT produces 50% less greenhouse gases than a conventional lab building

18 “下一代”實驗樓在34%的工作時間可以享受自然通風NEXT allows the workplace to be naturally ventilated 34% of occupied hours

19 實驗室平面布局方案示例通過把核心筒放置到建筑的邊緣，我們創(chuàng)造出更多的積極空間，讓員工可以選擇不同的辦公地點和辦公方式Test fit plan for today's lab Moving the core to the perimeter allows for more of the floor space to be activated and provides workers more choice in where and how to work

Further,by going all-electric,we found that NEXT would produce 50% less greenhouse gas emissions than a conventional lab building.Introducing passive strategies and optimising the building envelope,in combination with optimising the building systems,makes significant enough gains that,with the addition of both renewable energy onsite and carbon offsets offsite,the building can achieve carbon neutrality.

In terms of building systems,we adopted a modular building approach.The penthouse of the NEXT lab is more compact than one might expect because we specified on-floor air handling systems instead of a centralised system.For a building like this,we could even consider using recirculating fume hoods,which are becoming acceptable in some programme applications.We also optimised energy recovery and the cascading of air from non-lab space to lab space.

In some circumstances,if the layout calls for a reduced footprint for labs,it would be feasible to reduce the number of these on-floor air handlers.Conceivably some floors might not require these dedicated outside air source units,and that would result in more leasable tenant space.

8 Optimising Organisational Performance

As part of our study's measurable impacts,we looked at ways to optimise organisational performance by capitalising on the flexible floor plate.Buildings and spaces are now about elevating connectivity with people[6].That connectivity builds trust,which encourages collaboration and elevates culture– all leading to more idea generation.

To create a new hybrid sciences workplace that empowers people to connect and collaborate,we conducted a series of test fits based on our philosophical bias towards the benefits of aggregation.This approach is about blending science with influences that have not been merged before– such as the collaborative elements of tech workplaces,the experiential attributes of hospitality spaces,and the culture-building power of brand design.

One of the key issues in designing the floor layouts was providing maximum flexibility for the tenants.By laying out the grid in a 33-by-33-foot module and locating the core at the perimeter,it allows tenants the ultimate flexibility to design for their organisation's mission and culture.

Our first test fit plan looked at a conventional 50-50 split between lab space and workspace,a common ratio in today's life sciences buildings.With an eye to the future,we also looked at how we could design the space to reduce the size of the lab component but also create a flexible,agile workplace environment that allows people a sense of choice in where they work,as well as provide outdoor amenity spaces and the exterior stairwell that can serve as a communal,collaborative space.

To our minds,this is future of life sciences buildings– where we reduce carbon emissions and energy usage by cutting back on the square footage of lab space.That goal is being supported by the rise of computational modelling and machine learning,reduction in equipment size,reduction in sample sizes for experiments,and new automated processes.Accounting for those factors in combination with isolating the lab functions that require 100% exhaust,we studied a non-traditional option in which the lab occupies significantly less than 50% of the floor area.In that scenario,the rest of the non-enclosed lab space becomes a low-risk BSL-1 space.

In practice,this would be a highly progressive approach requiring us to work closely with our science tenants to validate whether it is appropriate for them.However,given that the winds of change will surely impact the shrinking of labs– coupled with the importance of our tenants' sustainable goals and the need for synergistic collaboration to advance scientific endeavours– this posits a future-forward approach.

9 A New Sustainable Model

Ultimately,NEXT is a platform that allows tenants and developers to reimagine what a science building can be.It is our call to action to shift from the past to a more resilient,sustainable,and inclusive future for lab buildings– a new model of efficient space usage,sustainability,and community connectivity that will be attractive to science building tenants and,by extension,the developer community.□